MiniPlex-2Wi NMEA 0183 multiplexer Manual

ShipModul
Marine Electronics
MiniPlex-2Wi NMEA 0183 multiplexer
Manual
MiniPlex-2Wi, V1.0
Firmware V3.17.x
Art.no.: 1125
Man. rev. A
© CustomWare, 2012
Introduction ....................................................................................................................... 3 Talkers and Listeners ....................................................................................................... 3 The Multiplexer................................................................................................................ 3 The MiniPlex-2Wi ............................................................................................................. 4 Connections ....................................................................................................................... 5 NMEA Signals .................................................................................................................. 5 NMEA Listener Ports/Inputs ............................................................................................... 5 NMEA Talker Ports/Outputs ............................................................................................... 5 Combining Ports .............................................................................................................. 6 SeaTalk .......................................................................................................................... 7 USB Port ........................................................................................................................ 7 WiFi Interface.................................................................................................................. 8 Power Supply .................................................................................................................. 8 Indicators .......................................................................................................................... 8 Driver Installation ............................................................................................................... 9 Windows 7 Installation ..................................................................................................... 9 Windows 2000/Vista/XP Installation ................................................................................. 14 Mac OS X Installation ..................................................................................................... 14 Data Throughput .............................................................................................................. 15 Configuration ................................................................................................................... 17 Menu ........................................................................................................................... 18 Controls ....................................................................................................................... 19 Host Settings.............................................................................................................. 19 Manual NMEA input ..................................................................................................... 19 Input Overflow ........................................................................................................... 19 Read Configuration ...................................................................................................... 20 NMEA Inputs/Outputs .................................................................................................. 20 Options...................................................................................................................... 22 NMEA Conversions. ..................................................................................................... 23 Sentence Filtering & Routing ........................................................................................... 25 Resetting the multiplexer ................................................................................................ 27 Firmware Update .............................................................................................................. 28 Mounting ......................................................................................................................... 28 Technical Reference .......................................................................................................... 29 NMEA Glossary .............................................................................................................. 29 Talker ID’s ................................................................................................................. 29 Sentence formatters .................................................................................................... 29 Translated SeaTalk datagrams ......................................................................................... 31 Firmware Update Error messages ..................................................................................... 32 MPX-Config INI file format .............................................................................................. 33 Proprietary NMEA Sentences ........................................................................................... 34 CF – Configuration ...................................................................................................... 34 CFQ – Request current configuration .............................................................................. 35 CN - Channel Number indicator ..................................................................................... 35 DR – Default Route ..................................................................................................... 35 DRQ – Request Default Route ....................................................................................... 36 FL – Filter .................................................................................................................. 36 FLQ – Request Filter List .............................................................................................. 37 ID – Talker ID ............................................................................................................ 37 IDQ – Request Talker ID’s ............................................................................................ 37 LDR – Loader message ................................................................................................ 37 OV – Overflow ............................................................................................................ 37 RESET – Reset the multiplexer ...................................................................................... 38 SP – Speed ................................................................................................................ 38 SPQ – Request Speed .................................................................................................. 38 TAG Block .................................................................................................................. 38 VER – Get Version ....................................................................................................... 39 WI – Wireless control................................................................................................... 39 Technical Specifications .................................................................................................. 42 Declaration of Conformity .................................................................................................. 43 2
Introduction
The MiniPlex-2Wi is an NMEA multiplexer that enables the connection of multiple NMEA 0183
instruments to each other and a computer and/or wireless devices. It is developed to solve a
fundamental problem with the NMEA 0183 standard.
The NMEA 0183 standard defines a communication protocol that enables navigation instruments to
exchange data with each other. A compass can send a bearing to a radar to enable a north-up
display, a GPS can send cross-track information to an autopilot in order to steer a programmed
course. The same GPS can also send information to the radar at the same time since the NMEA
0183 standard specifies that one device must be able to send data to up to four other devices.
NMEA data is made up of short text messages with a strict format called sentences and are humanreadable.
Talkers and Listeners
Communication using the NMEA 0183 protocol involves at least one
device that sends NMEA sentences and another device that receives
NMEA sentences. By convention, a sending device is called a talker
while a receiving device is called a listener. The picture on the right
shows such a minimal system: a gyrocompass sending heading
sentences to a radar.
Gyro
Radar
The NMEA 0183 standard specifies that a talker should have enough driving capability to talk to
four listeners. This is as easy to achieve as telling a story to an audience of up to four people. The
only requirement is to talk loud enough.
The picture left below shows such a situation.
PC
GPS
VHF
Depth
GPS
PC
Radar
Wind
Autopilot
Log
It gets complicated when several talkers must send data to one listener as shown in the picture on
the right. Unless that listener has multiple inputs, this is not possible without help. Simply
connecting talkers to one listener as shown is like four persons simultaneously telling you a
different story. You can make neither head nor tail of it. In electronics terms: the outputs of the
talkers will effectively short-circuit each other and the sentences they transmit will be corrupted.
This is where a multiplexer offers the solution.
The Multiplexer
A multiplexer, sometimes called ‘combiner’, has multiple inputs, each acting as a single listener
connected to a talker (the instruments). It has one or more outputs that are able to talk to multiple
listeners. These outputs deliver the combined data from the inputs.
A clever piece of software inside the multiplexer reads the NMEA sentences that are received on
the inputs simultaneously and stores them into queues, one for each input. Another part of the
software retrieves the sentences from the queues, one at a time, and sends them to the outputs of
the multiplexer. This way, four incoming streams of sentences are combined into one single
stream.
3
The picture below shows a typical setup with a multiplexer combining data from a wind instrument,
a compass and a GPS. This data is forwarded to a tablet and an autopilot using two different types
of outputs: an NMEA talker port called ‘Out1’ and a WiFi interface. The multiplexer forwards the
received NMEA sentences to the tablet and the autopilot at the same time.
The WiFi connection to the tablet is actually bi-directional: the tablet acts as a listener and a talker
at the same time. It receives NMEA sentences from the instruments to be processed by navigation
software on the tablet. This software can generate NMEA sentences to control an autopilot. These
sentences are sent to the multiplexer and forwarded to the autopilot. They can be combined with
the sentences received from the other navigation instruments.
Wind
In 1
Wifi
Comppass
In 2
USB
GPS
In 3
Out 1
Tablet
PC
Autopilot
Multiplexer
The picture also shows a computer in light grey that is connected to the USB port on the
multiplexer. The MiniPlex-2Wi also has a USB port with the same function as the WiFi interface.
This allows you to connect a second (fixed) computer while having the freedom of moving around
with your laptop, PDA, tablet or smartphone having access to the same navigation data as the
fixed computer.
The USB port is also used to update the firmware of the multiplexer and to configure the WiFi
interface. These tasks cannot be performed using the WiFi interface.
The MiniPlex-2Wi
The MiniPlex-2Wi is a multiplexer with four NMEA inputs (listener-ports), two NMEA outputs (talkerports), a WiFi interface and a USB port to connect to a computer. The multiplexer combines NMEA
data that is received on the listener ports In1 to In4 and sends this data to talker ports Out1 and
Out2, to the WiFi interface and to the USB port. The WiFi interface and the USB port are also used
to send data from a computer to the multiplexer to be forwarded to Out1, as well as to send
commands to configure the multiplexer.
Every NMEA input on the MiniPlex is galvanically isolated, sometimes called opto-isolation because
of the use of opto-couplers for isolation. An opto-coupler is a small device that transports
information by means of light instead of electricity.
A galvanically isolated input prevents unwanted currents to flow between instruments and the
multiplexer. These currents can damage equipment or interfere with radio signals and should
therefore be avoided. Galvanically isolated inputs are required by the NMEA standard.
The USB port of the MiniPlex is also galvanically isolated, which isolates the computer from the
navigation network and protects it against potential damage caused by ground loops or voltage
spikes.
Both NMEA outputs can drive up to four listeners each. Flexible routing options allow you to specify
which NMEA sentences are sent to these outputs.
Besides the basic functionality of combining NMEA data from multiple sources, the MiniPlex offers a
range of features to manage NMEA data like Sentence Filtering and Routing, Input Priority with
automatic switchover, testing of data integrity, Talker ID modification and SeaTalk® to NMEA
translation.
The MiniPlex can seamlessly be integrated into an existing Raymarine SeaTalk network when
SeaTalk mode is enabled. This mode changes one NMEA listener port into a SeaTalk input. When
connected to a Raymarine SeaTalk network, the multiplexer will translate SeaTalk data into NMEA
sentences and combine these with NMEA sentences that are received on the other listener ports.
Only one SeaTalk input is needed since the SeaTalk bus is a single-cable system that connects all
instruments together through one single cable. SeaTalk to NMEA translation in the MiniPlex works
only one-way. No NMEA sentences are converted into SeaTalk, the multiplexer just listens on the
SeaTalk bus.
4
Connections
NMEA Signals
Although the NMEA 0183 standard very clearly specifies the signal names, voltage levels and
connection methods, the reality is far from this ideal world.
The most important property of an NMEA port is that the connections or wires are labelled ‘A’ and
‘B’ and that it uses a differential signalling scheme. This means that data is transmitted on both
wires, but in ‘opposite direction’. Both wires are driven between 5V and 0V and opposite of each
other. This means when A is 5V, then B is 0V and vice versa. The advantage of this signalling
scheme is that it is very insensitive to electrical interference. NMEA ‘A’ and ‘B’ are often labelled as
NMEA ‘+’ and ‘-’ respectively. When connecting devices, simply connect NMEA ‘A’ to NMEA ‘A’ or
NMEA ‘+’ and NMEA ‘B’ to NMEA ‘B’ or NMEA ‘-’.
Things get complicated when manufacturers don’t follow the NMEA 0183 standard, which is very
often the case. Many devices have an NMEA port, which is really an RS-232 port. The only
resemblance with the NMEA standard is the format of the data transmitted. Electrically, they are an
entirely different world. The used signal names differ wildly and often lead to confusion. When a
device has a listener port with connections ‘Data In’ and ‘Data Return’ it is not clear whether this
input is galvanically isolated or ‘Data Return’ is simply another name for ‘Signal ground’
As opposed to the NMEA standard, many devices use a single-ended signalling scheme where data
is transmitted on one signal wire while a power/signal ground presents the return path for data.
Single ended devices often have connections named as TX and Gnd (transmit and ground) on the
talker port and RX and Gnd (receive and ground) on the listener port. Also used are Data Out, Data
In and Signal Ground. Mix these with ‘standard’ NMEA connections and confusion is imminent!
In general it is safe to connect a single ended talker port to a differential listener port. Connecting
a differential talker port to a single ended listener port however is less obvious. When NMEA ‘B’ of a
talker port is connected to the signal ground of a listener port, the ‘B’ signal is effectively shortcircuited to ground. A properly designed talker port can handle this abuse but it will result in fairly
high currents in long cables, which in turn leads to severe interference on SSB radios and possibly
on VHF radios too. In the worst case, the talker port will be destroyed.
To overcome this problem, the MiniPlex multiplexers provide a Com terminal on each talker port in
addition to the ‘A’ and ‘B’ terminals. This ‘Com’ terminal is similar to a signal ground. To connect a
talker port of the MiniPlex to a differential NMEA listener port, use the ‘A’ and ‘B’ terminals. Use the
‘A’ and ‘Com’ terminals to connect to a single-ended or RS-232 listener port.
NMEA Listener Ports/Inputs
The multiplexer has four listener ports or inputs, In 1 to In 4. Each listener port should be
connected to one instrument only. These inputs are completely floating and galvanically isolated
from the multiplexer, as specified in the NMEA 0183 standard.
Connect the A and B terminals of the listener port on the multiplexer to the A and B terminals of
the talker port on the instrument. These terminals may also be labelled as Data+ and Data-, TX+
and TX- , Out+ and Out– or ve+ and ve-.
Some instruments have single ended talker ports, with only one data terminal. Connect this
terminal to the A terminal on the multiplexer, and connect the ground of the instrument to the B
terminal on the multiplexer. The instrument’s data ground is often combined with its power supply
ground.
Out A/+
In A
TX/Out
In A
Out B/-
In B
Ground
In B
Instrument
Multiplexer
Instrument
Differential
Multiplexer
Single ended
NMEA Talker Ports/Outputs
Both talker ports or outputs can be connected to up to four instruments. Connect the A and B
terminals of the talker port on the multiplexer to the A and B terminals of the listener port(s) on
the instrument(s). These terminals may also be labelled as Data+ and Data-, RX+ and RX- ,
Out+ and Out– or ve+ and ve-.
5
Some instruments have single ended listener ports, with only one data terminal. Connect this
terminal to the A terminal on the multiplexer, and leave the B terminal on the multiplexer
unconnected. Connect the ground of the instrument to the Com terminal on the multiplexer. The
instrument’s data ground is often combined with its power supply ground.
Out A
In A/+
Out A
RX/In
Out B
In B/-
Out B
Ground
Com
Com
Multiplexer
Instrument
Multiplexer
Differential
Instrument
Single ended
Out A
In A/+
In A/+
RX/In
Out B
In B/-
In B/-
Ground
Com
Multiplexer
Instrument
Instrument
Instrument
Multiple differential and
single ended listeners
The shield terminals on the multiplexer (Shld) can be connected to the screen/shield of the cable if
available. This should always be done on one end of the cable only, preferably on the end that is
connected to a talker port.
Combining Ports
It is sometimes necessary to combine a listener and talker port of the multiplexer to connect to an
instrument. One of the most commonly used combinations is the connection of a GPS to the
multiplexer. While some GPS receivers have properly designed NMEA ports, many only have an
RS-232 port which is single ended with three terminals: TxD (data out), RxD (data in) and Ground.
The picture below shows how to connect such a GPS to the multiplexer.
TxD/Out
In A
Ground
In B
RxD/In
Out A
GPS
Out B
Com
Multiplexer
Connecting a GPS with a serial port
to the multiplexer
6
SeaTalk
SeaTalk® is a proprietary protocol developed by Raymarine®. This protocol is used for
communication between Raymarine navigation instruments like the ST40, ST50 and ST60 series.
To be able to use these instruments with commonly available navigation programs or to feed their
data into other non-Raymarine instruments, the SeaTalk data needs to be translated into NMEA.
Even Raymarine's own navigation software, Raytech Navigator, needs this translation.
The MiniPlex can be directly connected to a SeaTalk network. It will translate all SeaTalk data
required for navigation into NMEA sentences. Input In 4 can be set to SeaTalk mode
(SeaTalk -> NMEA) and should be connected as shown below:
Red
SeaTalk cable
Yellow
In 4A
In 4B
Multiplexer
Connection to a SeaTalk network
Note that the red and yellow wires are used! The shield of the SeaTalk cable is not connected to
the multiplexer.
USB Port
The USB port connects the multiplexer to a computer or a USB hub with the supplied cable. The
supplied driver provides a virtual COM port to allow navigation software to communicate with the
multiplexer. The USB port is bi-directional: the multiplexer sends NMEA data to the computer and
the computer can also send NMEA data back to the multiplexer. This data can be routed to
NMEA Out 1 and NMEA Out2.
The USB port is galvanically isolated from the multiplexer to prevent ground loops and excessive
currents that could otherwise destroy the multiplexer or the USB port of the connected computer.
The USB connection supports flow control, which is needed when waypoints and routes are sent
from the computer to a GPS through the multiplexer. While normal NMEA sentences are sent at
regular intervals, waypoints and routes are sent ‘in one go’ without any pause between these NMEA
sentences. This fills up the queue in the multiplexer almost immediately after which the multiplexer
discards the remaining waypoints and routes. The GPS now only receives a few waypoints and
partial routes.
Flow control prevents this from happening. When the queue in the multiplexer is almost filled, the
multiplexer signals the computer to stop sending data. When the queue is sufficiently emptied, the
multiplexer signals the computer to continue. This requires a special setting in your navigation
software, which is mostly called ‘Flow Control’. This setting can mostly be found in the port settings
of your software. Set the Flow Control to Hardware or CTS/RTS. This Hardware flow control is
virtualized over the USB connection. Do not use Xon/Xoff flow controls since this uses special
characters instead of a (virtual) signal. These characters are not part of the NMEA standard and
therefore ignored by the multiplexer.
7
WiFi Interface
Through its WiFi interface, the MiniPlex-2Wi can communicate with a wireless device such as an
iPad, iPhone, an Android based smartphone or tablet, a PC or a Mac. The multiplexer creates a
wireless Access Point 820.11b+g interface with the following parameters:
SSID (name):
IP address:
Port:
Protocol:
MiniPlex-2Wi:xx:xx
10.0.0.1
10110
TCP
The xx:xx’s are the last two bytes of the MAC address of the multiplexer as printed on the serial
number sticker. This uniquely identifies a MiniPlex-2Wi from similar devices.
A wireless device that connects to the MiniPlex-2Wi will get an IP address from the built-in DHCP
server. It is not necessary to set a fixed IP address in your device.
Configure your navigation software to connect to IP address 10.0.0.1 and port 10110 using the TCP
protocol.
The MiniPlex-2Wi supports only one connection WiFi connection at a time. The WiFi interface and
the USB port operate simultaneously and with the same priority. This allows an on-board fixed
computer to be connected simultaneously with a wireless device.
The WiFi interface cannot be used to update the firmware of the MiniPlex-2Wi or to configure the
WiFi interface using $PSMDWI commands (see the Technical Reference, Proprietary NMEA
Commands). All this has to be done using the USB interface.
Power Supply
The multiplexer must be powered from an externally supplied DC voltage from 8 to 35V. The power
supply connection is protected against reversed polarity.
Indicators
The multiplexer has three LEDs. The green LED indicates the reception of valid NMEA data on the
listener ports or from the network. It only blinks on valid NMEA sentences that start with a ‘$’ or ‘!’
and end with a CR and LF character, thus indicating a proper connection and polarity of the
connected instrument. In case of a reverse polarity of a connected talker, the green LED will not
blink. The green LED also blinks every two seconds to indicate that power is present and it is
operational. This blink is slightly dimmer than a blink on data reception.
The red LED indicates a queue overflow, in case more data is received than can be transmitted.
See section ‘Data Throughput’ for options to resolve this situation.
During a firmware update, the red LED will be lit continuously when the update is in progress while
the green LED blinks on the reception of firmware data from the computer. This will give a visual
indication of the update process.
The yellow led indicates the status of the WiFi connection: and has three possible states:
Off:
On:
Blinking:
The MiniPlex is configured to connect to a WiFi Access Point but the connection failed.
The WiFi Access Point is active and ready for use.
An application has connected using TCP.
8
Driver Installation
To use the MiniPlex-2Wi with your computer using the USB interface, a device driver needs to be
installed. This driver creates a virtual COM port, which can be opened with any navigation software
just like any other COM port. Drivers are supplied for Microsoft Windows (Windows 2000, Windows
XP, Windows Vista, Windows 7) and Apple’s Mac OS X.
If you plan to use the MiniPlex-2Wi using the WiFi interface only, no driver needs to be
installed. Firmware updates however can only be loaded using the USB interface.
Windows 7 Installation
When the MiniPlex is connected to the computer for the first time, Windows will automatically
download the most recent drivers from the Windows Update Service when an Internet connection is
available. Without connection to the Internet, Windows will eventually tell you that the ‘Device
Driver software was not successfully installed’.
The following procedure allows you to install the drivers for the MiniPlex manually.
Open Control Panel -> System and Security -> Device Manager.
In the Device Manager, there will be a ‘ShipModul MiniPlex-2Wi’ listed under ‘Other Devices’ as
shown in the picture.
Right-click on the MiniPlex entry and choose ‘Update Driver Software...’ from the menu that
appears. This will open the following window:
9
Choose ‘Browse my computer for driver software’. In the following window, choose the location of
the driver (the ‘\USB Driver\Windows’ subfolder on the MiniPlex Driver & Utility CD) and press
‘Next’.
10
When Windows has successfully installed the driver, the following window appears:
You can close this window.
The Device Manager will now list an USB Serial Port under Other Devices:
11
Right-click on the USB Serial Port entry and choose ‘Update Driver Software...’ from the menu that
appears. This will open the following Window:
Choose ‘Browse my computer for driver software’. In the following window, choose the location of
the driver (the same location as last time will be shown again) and press ‘Next’.
12
When Windows has successfully installed the driver, the following window appears:
You can close this window.
The Device Manager will now list a ShipModul MiniPlex NMEA Multiplexer under Universal Serial Bus
controllers and a MiniPlex Serial Port (COMx) under Ports (COM & LPT).
13
Windows 2000/Vista/XP Installation
When the multiplexer is connected to a USB port for the first time, Windows will detect new
hardware and prompts you for a driver. Insert the supplied CD into the drive and follow the
instructions on your screen. If you have an Internet connection, you can let Windows search the
Internet for updated drivers. Otherwise, when asked to automatically search for drivers, answer no
and choose the option to tell Windows where to find the driver. The driver can be found on the
supplied CD, in de folder ‘\USB Driver\Windows’
The installation on Windows is a two-step process. First, the driver for the multiplexer will be
installed. Next, Windows will detect a USB Serial device and will install a second driver. On
Windows XP systems, there can be a delay of up to 10 seconds between the installation of both
drivers, which sometimes leads to the conclusion that the installation is complete after the first
driver is installed which is not the case. On Windows Vista and Windows 2000 systems, there is
only very little delay.
When the installation is complete, a new virtual COM port will be created. This COM port is shown
in MPX-Config as COMx (vcp) where ‘x’ is a number. Select this port in your navigation software.
The ‘vcp’ extension as shown in MPX-Config will not be visible in your navigation software.
If necessary, the number of this COM port can be changed in the Windows Device Manager. Click
on the ‘+’ sign next to the entry marked as ‘Ports (COM & LPT)’. This will expand the entry to list
all available COM ports on your computer. The port for the multiplexer is listed as ‘MiniPlex Serial
Port (COMx)’ where ‘COMx’ is the name of the newly created serial port.
To change this port number, double click on the MiniPlex Serial Port (COMx) entry to open the
property page for this port. Next, select the Port Settings tab and click on the Advanced…
button. In the appearing window the used port number can be changed. Do not change any other
setting in this window.
It is possible to select a port number that is already present on the computer, like COM1. The
original COM1 port will then be disabled as long as the multiplexer is connected to the computer.
This feature allows the port number to be set in a low range from COM1 to COM4, to accommodate
software that only allows COM1 to COM4 to be selected.
More than one multiplexer can be connected at the same time. Every new unit will create a new
virtual COM port. The number of the COM port will always be assigned to the same multiplexer
regardless of the USB port being used.
Windows allows a maximum of 256 COM ports. However not all software may be able to select
COM ports numbered above COM9.
When installing updated drivers, uninstall the original drivers first with the
Add/Remove Programs icon in the Control Panel or use the Update Driver button on the
Driver page of the MiniPlex Serial Port property-page.
Mac OS X Installation
The OS X driver is available as a disk image file (.dmg) and can be found on the supplied CD in the
‘USB Driver’ folder. Run the installer by double clicking on the icon. Follow the instructions on the
screen. When the installation is complete, plug in the USB cable of the MiniPlex. The MiniPlex will
show up in the ports list of your navigation software as MiniPlex-xxxxxxxx where the xx’s represent
the serial number of the MiniPlex.
14
Data Throughput
Depending on the configuration of the multiplexer, NMEA sentences are sent to one or more
outputs with different communication speeds. A situation could arise where more data is received
than can be transmitted because of the different speed settings of the inputs and outputs. Such a
situation leads to an overflow of the input queues of the multiplexer. When an NMEA sentence is
being received while a queue is full, this sentence is discarded. Only complete NMEA sentences are
stored and forwarded. This event is indicated by the red LED, which will blink briefly when a
sentence is discarded and the indicators in the Input Overflow section on the MPX-Config screen.
In its default factory setting, as shown below, the data flow through the MiniPlex is very
straightforward. First of all, the data that is received on the NMEA inputs is always sent to the
computer via the host interface(s).
In addition to this, the same data is also routed to Out2, as indicated by the checkboxes in the
section Input Settings. The section Output Settings shows that data from the computer (Host)
is routed to Out1 only.
This basic configuration allows you to combine data from navigation instruments and send it to a
computer using the Host port(s) and to a chart plotter connected to Out2 while the computer can
control an autopilot connected to Out1.
The default speed setting of the inputs and outputs ensures that there will be no queue overflows.
Please note that the default communication speed of Out2 is 38400 baud. Most chart plotters
support this high speed for reception of AIS data. However, if you want to connect this output to a
repeater display or a VHF radio, the speed of Out2 must be lowered to 4800 baud. If this leads to
excessive overflows, it is necessary to reduce the amount of data sent to this output. This can be
achieved by changing the default routing settings (disable certain inputs for Out2) or by using the
Sentence Filtering & Routing facility of the MiniPlex.
Now back to data throughput. The standard speed of an NMEA port is 4800 Baud or bits/second,
representing 480 characters per second. It is quite obvious that when four inputs receive data at
480 char/s and all of this data must be sent out again on an output with the same bandwidth of
480 char/s, a huge problem will arise. In the default configuration this problem does nor occur
because the speed of Out2 is set to 38400 Baud (3840 char/s). When Out2 is not used, set it to
the highest speed or disable routing of any of the inputs to Out2. When Out2 is connected to a
chart plotter, try to choose the highest speed the plotter will accept.
If data from more than one input needs to be routed to an output operating at 4800 Baud,
problems with data throughput can arise when too much data is sent to this output.
NMEA data tends to be sent in bursts. Some devices line depth sounders or wind instruments only
send one sentence per second while a GPS may send bursts of up to 13 sentences every two
seconds. While the average throughput over time may be low, an input might fill its queue quite
rapidly when a burst of sentences is received. The queues in the MiniPlex are quite large and may
contain up to 30 sentences of GPS data.
A couple of occasional blinks of the red LED over a period of a few seconds means that large bursts
of sentences are received and a queue is hitting its limit. Some sentences are discarded but most
of them will be passed without problems. Such a situation is totally acceptable and would mean
that for instance one depth, wind or position update is missed every few seconds.
15
A quite different situation may arise with some fluxgates or gyrocompasses. These devices may
send their heading sentences with a speed up to 40 sentences per second! Instead of queuing a
burst of sentences every one or two seconds, the multiplexer must queue a constant stream of
sentences, possibly utilizing the maximum bandwidth of the multiplexer. Such a situation can lead
to a queue that is constantly filled up to its maximum capacity. This in turn results in heading data
that can be up to 20 seconds old when it is forwarded, which is totally unusable for any autopilot to
steer on. Enabling the Real Time option for this input can solve this specific problem. This option
bypasses the queue entirely. Only one sentence will be stored now and sent out when the time slot
for this input arrives. Outside its time slot, incoming sentences will be discarded. A lot of heading
sentences will be lost now but the ones that are passed, are passed almost immediately. Hence the
name ‘Real Time’.
When the red LED is blinking severely or stays on almost
continuously, it is advisable to investigate which instrument or
input leads to this overflow. The MPX-Config utility will show on
which input the overflow occurs by a blinking indicator in the
NMEA Input Settings section. Opening the Statistics window
from the Tools menu will give an insight about the amount of data
in a queue and whether it is filled constantly or occasionally.
Some general rules are applicable for reducing overflow situations.
A simple rule of thumb is that an overflow can never occur if the
speed of an output is equal or higher than the combined speeds of
all inputs that are routed to that output. For example: if the
multiplexer is in its default configuration and all four inputs are set
to 4800 Baud, the minimum output speed equals 4 x 4800 =
19200 Baud. This rule is only a hard rule when the input
bandwidth is fully utilized i.e. an instrument is sending data
continuously. This is hardly ever the case. As mentioned earlier,
NMEA data is often sent in bursts, resulting in a much lower overall
bandwidth. It could be perfectly feasible to have a system with
four instruments connected to the multiplexer, while running all in- and outputs on 4800 Baud
without a single overflow.
There are several ways to resolve overflow situations:
1.
Configure the instruments on the listener ports to send less data or with greater intervals.
GPS receivers can sometimes be configured for this.
2.
Use the sentence filter of the multiplexer to block unwanted sentences. Unwanted
sentences are discarded immediately and do not occupy queue space or bandwidth.
3.
For sentences that should not be blocked, setting a divisor in the sentence filter may lower
their rate. A gyro may be ‘throttled down’ to 10 sentences per second or even less. From
the GPS output, the rate of the sentences containing satellite information could be lowered
to once every 10 seconds instead of being output every time a position is output by the
GPS.
4.
Use the routing options to select which input is routed to an output or use the routing
options in the sentence filter to selectively route NMEA sentences to an output.
5.
Increase the speed of the NMEA output that causes the bottleneck. This will only work
when the connected equipment also supports higher communication speeds.
16
Configuration
The multiplexer can be configured with a configuration program called MPX-Config. This program
can be found on the accompanying CD. There is no installation procedure for this program, just
start it from the CD or copy it to a suitable folder on the hard disk of your computer and start it
from there.
The multiplexer itself is configured with proprietary NMEA sentences. MPX-Config sends these
sentences to the multiplexer when you change a control on the screen.
All configuration settings are stored in the multiplexer’s non-volatile memory. These settings are
retained without power supply.
Screenshot of MPX-Config
The screen is divided into four sections from top to bottom: the menu, the data area, the control
area and the status bar. The menu basically controls the MPX-Config program. The data area
shows the NMEA sentences that are received from the multiplexer. These sentences include the
NMEA data received by the multiplexer on its inputs as well as status messages generated by the
multiplexer. The latter can be recognised fairly easy: they all start with ‘$PSMD’. The control area
contains controls that determine the operation and configuration of the multiplexer. The status bar
shows the name or type of multiplexer that is connected, its internal software (firmware) version
number and its serial number. This information is useful when you need technical support. Also
shown are the optionally loaded or saved configuration file and a line counter when you have
started a log file.
17
Menu
The menu contains two sub-menus: File and Tools. The File menu contains the following options
to choose from:
Start Log…
Start writing NMEA data to a log file. A log file is a plain text file and
can later be opened by any text editor to examine the data. A log file
can be a useful tool for diagnostic purposes and is often requested by
us for support. If you enter a new filename in the file dialog window, a
new log file is created. If you choose an existing file, this file will be
overwritten with new data. The Log counter on the status bar will show
the number of NMEA sentences that are currently written to the log file.
Timed Log…
Start writing to a log file with the addition of a time stamp at the
beginning of each NMEA sentence.
Stop Log
Stop writing NMEA data to the current log file and close that file.
Load Configuration…
Load a previously saved configuration file into the multiplexer. The
current configuration will be overwritten. A configuration file stores all
settings made with MPX-Config. See the Technical Reference section for
a description of this file format.
Save Configuration
Save the current configuration to a file. If a file was previously opened,
that file will be overwritten. If no file has been opened before, you will
be prompted for a file name. The name of the currently loaded
configuration file is shown on the status bar.
Save Configuration As… Save the current configuration to a new file.
Update Firmware…
Load new firmware into the multiplexer. From time to time, new
features are developed for the multiplexer or bugs are fixed. New
firmware image files will then be made available through our website.
These image files can be downloaded to your computer and loaded into
the multiplexer with this option. This option will only be visible when
your multiplexer supports firmware updates. This is the case from
firmware version 3.00 and up. Multiplexers containing lower firmware
versions need to be returned to our factory for an update.
Exit
This option exits MPX-Config.
The Tools menu contains the following options to choose from:
Clear Screen
Clear the data area on the screen. New sentences will be displayed
from the top.
No Scroll
Normally, incoming NMEA sentences are displayed from the top down
and when the bottom of the data area has been reached, all sentences
are scrolled up one line before the new one is show. When No Scroll is
activated, a list of incoming NMEA sentences will be displayed that will
be refreshed constantly when new similar sentences are received. A
scroll bar will appear when the list grows beyond the length of the data
area. This feature allows you to closely examine the types of sentences
that are received from the connected instruments. Any proprietary
NMEA sentences that are generated by the multiplexer are also listed.
The can be recognised by the firsts four characters, which are ‘$PSMD’.
Show Statistics
This option opens a new window that will be displayed on top of the
MPX-Config window. This window show bars that indicate how much
NMEA data is stored in the input queues. This is a useful option for
diagnosing data congestion and overflow situations as mentioned in
paragraph ‘Data Throughput’. A queue that is filled constantly can lead
to unacceptable delays in data transfer.
About
Show a window with version information.
18
Controls
The control area of the MPX-Config screen allows you to configure the multiplexer. It is devided in
two parts: a small part on the left contains the Host Port settings, the Manual NMEA Sentence
Input, the overflow indicators and the Read
Configuration button. These items are available at all
time. The largest part on the right contains all settings that
control the operation of the multiplexer. These settings are
logically grouped on tabbed pages. When started for the
very first time, the NMEA Inputs/Outputs tab is shown. On
exit, MPX-Config stores the currently active tab and shows
this on the next startup.
Host Settings
Before being able to configure the multiplexer, select the
communication port to which the multiplexer is connected
in the Host Settings. These settings control the
communication settings of your computer or tablet, which
are called the Host. Nothing is changed in the multiplexer
here. Because there are several ways to connect a host to
the multiplexer, you will find a number of possible ‘ports’ in
the Port selector, ranging from available COM ports on your
computer to TCP and UDP.
Depending on the kind of selected port, the Host Settings
section changes its appearance. When you select a COM
port, the section shows a Speed selector to select the
communication speed of the COM port. When TCP or UDP is
selected, the section shows an entry field for an IP address.
In case of a virtual COM port (a COM port created by the USB driver of the MiniPlex), the COM port
is marked with ‘(vcp)’ and the Speed setting is irrelevant.
If you connect to the multiplexer using TCP, enter the IP
address of the multiplexer in the Host field as shown. The
IP address of the MiniPlex-2Wi is 10.0.0.1.
Once you have set the desired settings, click on the
Connect button to start the connection to the multiplexer.
When a virtual COM port has been selected, the Speed setting will change to Automatic and will
be disabled. MPX-Config will now retrieve the current settings from the multiplexer and enable the
tabbed configuration pages.
If a ‘Multiplexer does not respond’ – message appears, you may have selected the wrong COM
port. In case of a wrong IP address, an ‘Unable to connect’ –message appears.
If you exit MPX-Config, the port settings will be saved and reloaded on the next start-up of MPXConfig.
When you select a different port while being connected, MPX-Config disconnects from the
multiplexer and you have to click on Connect again.
Manual NMEA input
MPX-Config allows manual entry of NMEA sentences for testing, configuration etc.
Type the desired NMEA sentence in the edit box and click on the Send button or press the enter
key. MPX-Config will keep a history of entered sentences/commands.
Preceding the NMEA sentence with a ‘$’ is optional, MPX-Config will add it if it is omitted. The input
is case sensitive, so whatever you type will be sent to the multiplexer literally. Since all NMEA
commands are uppercase, you have to enter them as uppercase.
Any sentence starting with ‘$PSMD’ will be recognized by the multiplexer as a configuration
command and will be processed as such. Any other sentence will be sent to the NMEA outputs.
Input Overflow
The overflow indicators show which input suffers from a queue overflow. See the section ‘Data
Throughput’ for ways to prevent overflow situations with different instruments.
19
Read Configuration
Clicking this button will retrieve the current configuration settings from the multiplexer. MPX-Config
will do this automatically when you click on the Connect button but it can be useful to re-read the
configuration at a later stage.
When the wrong port is selected, MPX-Config will show a ‘Multiplexer does not respond’ - message
and all controls will be disabled (greyed).
The status line on the bottom of the MPX-Config window will show the name of the multiplexer, the
internal software (firmware) version and the serial number.
NMEA Inputs/Outputs
This page allows you to set the communication speeds of the NMEA inputs and outputs of the
multiplexer, various options related to the inputs or outputs and the default routing of NMEA
sentences. The settings are grouped together for the inputs and the outputs.
Speed
This sets the speed of each NMEA input or output. 4800 Baud is the standard speed for navigation
equipment. Some fluxgate or gyrocompasses operate at 9600 Baud to accommodate the higher
throughput of 20 headings per second or more. AIS equipment operates at 38400 Baud.
If you change the speed of In4, the speed of Out1 will be changed too. In 4 and Out 1 share the
same communication port inside the multiplexer and therefore always have the same speed. Out 1
is generally used to control an autopilot and should be left at 4800 Baud for this purpose. The
settings for In4 and Out1 are disabled and fixed to 4800 Baud when SeaTalk translation is
enabled on the Options page.
Care should be taken when selecting other speeds than 4800 Baud with respect to possible queue
overflows. See paragraph ‘Data Throughput’ for more information.
Talker ID
The multiplexer can change the Talker ID of incoming sentences. The first two characters of an
NMEA sentence represent the Talker ID, indicating which instrument (talker) the sentence is
originating from. Normally you don’t need to change this and these fields can be left blank (‘--’).
Changing the Talker ID of a sentence might be necessary for instance when using a GPS compass.
Such a compass often outputs a true heading sentence starting with ‘$GPHDT’. Many instruments
or navigation programs however require a true heading that starts with ‘$HE’, which is the
standard Talker ID for true heading devices. By entering ‘HE’ in the Talker ID field of the input
connected to the GPS compass, the incoming ‘$GPHDT’ sentence will be changed into ‘$HEHDT’.
Setting a Talker ID can also be useful when similar instruments are connected to the multiplexer
while the navigation software must be able to distinguish between the data from these
instruments. A catamaran for instance could have a depth sounder in each hull, sending similar
sentences to the navigation software. Setting the Talker ID for those inputs to ‘D1’ and ‘D2’
respectively allows the software to recognise both depth readings separately.
Enter the Talker ID in the edit box of the desired input and press the Enter to send the setting to
the multiplexer. A Talker ID may consist only of upper case characters and numbers. See the
Technical Reference section for an overview of the most commonly used Talker ID’s.
When the Talker ID is changed, the background turns yellow to indicate that de modified Talker ID
has not yet been sent to the multiplexer. Pressing Enter will send all Talker ID’s to the multiplexer
20
and the background colour will return to white again. It is possible to change all Talker ID’s first
and press Enter after changing the last one. Starting at the Talker ID field of input 1, pressing the
Tab key will jump to the Talker ID of the next input.
Clicking the Read Configuration button will read the Talker ID settings from the multiplexer. Any
modified Talker ID’s that have not been sent to the multiplexer (yellow background) will revert to
their original values. To clear a Talker ID, simply clear the edit box(es) by selecting them with the
cursor and press the Del or Backspace key on your keyboard and finally press Enter. An empty
Talker ID setting will show two dashes.
Real-Time
The Real-Time option bypasses the queue of an input. All incoming NMEA sentences are stored in a
queue - one for each input. Each queue can store several NMEA sentences, waiting for processing.
A GPS can output up to 13 sentences at once, every one or two seconds, and a queue can store
these sentences until they are processed and retransmitted.
An electronic compass however, only sends one heading sentence each time, but this can be up to
20 times per second. Due to this high frequency, a queue will be filled with a lot of heading
sentences. The ones that are retrieved from the queue for retransmission will therefore contain a
heading that can be up to 20 seconds old – much too old for a valid indication or for an autopilot to
steer on. This situation will also be indicated by the overflow LED on the multiplexer and the
indicators in the Input Overflow section on the MPX-Config screen.
When the Real-Time option is enabled, the queue for that input is bypassed. Only one single
sentence will be stored, waiting to be retransmitted within 200ms. The result is that some heading
sentences will be discarded but the ones that are passed have no significant delay.
This option should only be used for instruments like an electronic compass that output only one
single sentence. If used for a GPS for instance, only the first sentence of an entire group will be
passed, the rest will be discarded.
To Output 1 & 2
These options allow you to set the default route from the inputs to the outputs. The default route
as showed in the picture routes all inputs to Out2 and none to Out1. By default, the inputs are
always routed to the host port(s).
The default route is applied to an input when no specific route for that input exists in the sentence
filter. A match in the sentence filter always takes precedence over the default route.
NMEA Conversions
The result of NMEA conversions (see Options page) can be treated as if they were received on a
separate – virtual - input. The same settings of the real inputs can be applied to the NMEA
conversion results.
Computer Data
This controls the default route from the host (both USB and WiFi) to both NMEA outputs. Possible
options are No, Yes or Override.
No
No data from the host is routed to the NMEA output.
Yes
Data from the host is routed to the NMEA output and mixed with data from the inputs.
Override
Data from the host is routed exclusively to the output and takes precedence over the
data from the inputs. When the host sends data to the multiplexer, no input data is
routed to the output. When the host stops sending data however, data from the inputs
will be routed to the outputs after a time out of 10 seconds.
The Override option is very useful when sailing alternately with our without a laptop or tablet.
Consider a typical set-up as shown below:
Wind
In 1
Wifi
Comppass
In 2
USB
GPS
In 3
Out 1
Multiplexer
21
Tablet
PC
Autopilot
When the tablet is connected, it will receive all information from the instruments and the
navigation software calculates the course to steer and drives the autopilot accordingly. Because the
tablet is sending NMEA data, the multiplexer routes this data exclusively to Out 1. The autopilot
will therefore receive information from the tablet only.
When the tablet is not connected or the navigation software is not sending any data, the
multiplexer automatically routes the inputs to Out1, sending the data from the instruments to the
autopilot. This way, the autopilot will receive course information directly from the GPS.
Options
On the Options page several options and conversions can be chosen.
Priority
This option deletes duplicate NMEA sentences received on multiple inputs. When enabled, the
multiplexer assigns a priority to incoming NMEA data based on the input on which it is received.
The USB port and WiFi interface have the highest priority, followed by NMEA In 1, In 2, In 3 and
In 4 in descending order. NMEA conversion results have the same priority as the input that
received the source of the conversion.
If for instance two GPS receivers are connected to input 1 and 2 and both GPS receivers output
GPRMC sentences, only those from the GPS on input 1 are passed. This feature can be useful to set
up a second GPS as a backup for the main GPS.
The multiplexer only uses the Sentence Formatter (the ‘RMC’ part) for comparison - the Talker ID
(the ‘GP’ part) is ignored.
Another useful application of Priority is when a GPS and an AIS transponder are connected to the
multiplexer. An AIS transponder often outputs sentences from its internal GPS. A navigation
program will now receive GPS data from two sources that might differ in position due to GPS
inaccuracy. This will lead to navigation errors. When the AIS transponder is connected to input 1
and the GPS to input 2, all the NMEA sentences from the AIS transponder is passed while duplicate
NMEA sentences (e.g. GPRMC) from the GPS are blocked. When the AIS transponder fails, GPRMC
sentences from the GPS will be passed again after an adjustable timeout.
Note that the priority system does not block an entire input, it only blocks duplicate sentences.
Sentences received from the GPS that are not received on the AIS input are passed.
The following example shows what is passed and what not. The left column in the table shows
sentences from the AIS transponder on input 1 and the right column sentences from the GPS on
input 2. The sentence that is greyed in the table is blocked by the priority system. The table shows
that only the RMC sentence from the GPS is blocked.
The priority feature can store up to 50 different sentence types to determine their priority. A time
out mechanism ensures that sentences received on lower priority inputs are passed again after an
adjustable time out when their duplicates on higher priority inputs are no longer received.
Check GPS status
Normally, the priority system detects the absence of NMEA sentences. With Check GPS status
enabled, it detects invalid sentences, specifically from a GPS.
AIS
GPS
(In 1)
(In 2)
When a second GPS is connected as a backup to the first GPS, the first
GPS must completely fail (stop sending data) before sentences from
GPRMC
GPRMC
the second GPS are passed. In a situation where the first GPS no
longer receives any signal from satellites (broken antenna, cable etc.),
AIVDM
GPGGA
it will still output NMEA sentences and the priority system will not fall
22
back to the second GPS. When Check GPS status is enabled, the multiplexer checks the Status
field of GPS sentences. When the Status field indicates ‘Invalid data’, the multiplexer will block
these sentences, allowing the priority system to time out and pass sentences from the second GPS.
Sentences of which the Status flag is checked are APB, GGA, GLL, RMA, RMB, RMC, VTG and XTE.
Time Out
This setting allows you to set the time it takes before sentences from a lower priority input are
passed.
Channels
This option inserts channel number information in the NMEA stream that is sent to the host
interface(s).
When NMEA is selected, each received NMEA sentence is preceded by a $PSMDCN sentence to
indicate on which NMEA input the following sentence was received. The following example shows
that the IIGGA sentence was received on input 1, the GPGGA sentence on input 2, the IIGLL
sentence on input 1 and the HEHDT sentence on input 3.
$PSMDCN,1*1A
$IIGGA,143357.999,5301.0061,N,00635.5479,E,1,06,1.9,90.0,M,,,,0000*2E
$PSMDCN,2*19
$GPGGA,143357.999,5301.0061,N,00635.5479,E,1,06,1.9,90.0,M,,,,0000*39
$PSMDCN,1*1A
$IIGLL,5301.0061,N,00635.5479,E,143357.999,A*22
$PSMDCN,3*18
$HEHDT,67.0,T*1E
When TAG Blk is selected, the multiplexer adds an NMEA 0183 V4.0 TAG block to each sentence
that is sent to the host interface(s). This TAG block contains a source identification parameter
indicating on which input that sentence was received. The following example shows the same data
as above, but with TAG blocks added.
\s:mch1*1E\$IIGGA,143357.999,5301.0061,N,00635.5479,E,1,06,1.9,90.0,M,,,,0000*2E
\s:mch2*1D\$GPGGA,143357.999,5301.0061,N,00635.5479,E,1,06,1.9,90.0,M,,,,0000*39
\s:mch1*1E\$IIGLL,5301.0061,N,00635.5479,E,143357.999,A*22
\s:mch3*1B\$HEHDT,67.0,T*1E
Channel numbers allow distinguishing between similar data from different instruments, like two
depth sounders on the same boat.
See the Technical Reference section for a description of the TAG block.
SeaTalk on In 4
To receive SeaTalk® data from Raymarine® instruments and convert it into NMEA sentences, this
option must be enabled. SeaTalk is a proprietary protocol developed by Raymarine and it is used
for data exchange between Raymarine navigation instruments like the ST40, ST50 and ST60
series. To be able to use these instruments with commonly available navigation programs or to
feed their data into non-Raymarine instruments, the SeaTalk data needs to be translated into
NMEA sentences. See the Technical Reference section for an overview of translated SeaTalk data.
Selecting this option will automatically set In4 and Out1 to 4800 Baud and disable the speed
setting.
SeaTalk Priority
This sets the priority of the SeaTalk data. It can be either Highest (SeaTalk - In1 - In2 - In3) or
Lowest (In1 - In2 - In3 - SeaTalk).
NMEA Conversions.
The NMEA Conversions allow you to convert specific NMEA sentences into new NMEA sentences.
The originating sentence used for a conversion is forwarded as usual but if desired, it can be
blocked using the sentence filter. The conversion results can be routed anywhere using the default
route and Sentence Filter and are available on the virtual input NMEA Conversions and input ‘C’
in the sentence filter.
Magnetic to True Heading (HDG, HDM -> HDT)
If this option is enabled, the multiplexer will generate an HDT sentence (true heading) when an
HDG or HDM sentence (magnetic heading) is received. If the HDG sentence contains a magnetic
variation, it is used to calculate the true heading from the magnetic heading. Otherwise the
magnetic heading value is just copied.
This option can be useful when a device needs a true heading while only a fluxgate compass is
available on board. Many satellite telephones for instance need a true heading to be able to direct
their antenna to the right communications satellite.
23
GPS Speed to Log Speed (VTG -> VHW)
If this option is enabled, the multiplexer will generate a VHW sentence (water speed and heading)
when a VTG sentence (course over ground and ground speed) is received. The VTG sentence is
generated by a GPS and the VHW sentence by a log. Often the paddlewheel of a log gets stuck
when fouled and this option offers a solution to substitute the log data with GPS data.
Reverse Heading (HDT)
This option allows you to reverse the true heading in a received HDT sentence. When an HDT
sentence is received, the multiplexer generates a new HDT sentence with 180° added to the
original heading. This can be used to provide two opposing navigation stations on ferries with a
heading from the same gyro. Use the default route or Sentence Filter to route each sentence to a
different NMEA output and only one to the host if needed.
24
Sentence Filtering & Routing
The Sentence Filtering & Routing feature is the most powerful feature of the MiniPlex. It allows you
to filter and route NMEA sentences based on the Address Field of an NMEA sentence (the ‘GPRMC’
part) and optionally reduce the rate of the sentence. Sentences can be passed or blocked, specified
by input (filtering) and they can be forwarded to specific outputs (routing). Up to 50 rules can be
entered, either manually or by capturing the NMEA sentences received by the multiplexer on its
inputs.
Each filter/routing rule in the list consists of the Address Field of an NMEA sentence, checkboxes to
specify the source inputs and destination outputs and a divisor factor to reduce the sentence rate.
The buttons on the right allow you to modify the list and to store it into the multiplexer.
Editing the list
It is important to know that all modifications and additions are made to the list that is loaded in
MPX-Config. The current list is automatically loaded when you connect to the multiplexer or when
you click on the Read Configuration button. After editing, the list must be stored in the
multiplexer to be effective.
The Filter & Routing list contains the following columns:
Inputs:
H:
1-4:
C:
This input represents the combined input from the host interfaces.
NMEA inputs 1 to 4.
NMEA Conversion results.
Sentence: The Address Field of an NMEA sentence. This fully specifies the type of NMEA sentence
to be filtered/routed. A ‘-’ will match any character. If for instance ‘--GLL’ is entered,
any sentence that ends on GLL will match, regardless of the first two characters (the
Talker ID). A ‘P----’ will match on every proprietary sentence starting with $P.
The Sentence field must contain 5 characters
Div:
Outputs:
1,2:
PC:
W:
Divisor field. A number from 0 to 99 will divide the sentence rate by the number
entered. If this field contains a divisor of 5 for instance, every fifth occurrence of this
sentence will be passed.
NMEA outputs 1 and 2.
The ‘wired’ host connection of the multiplexer (RS-232, USB, Ethernet).
The wireless host connection of the multiplexer (WiFi, Bluetooth).
Clicking on a checkbox changes its state from checked to unchecked and vice versa. This
determines whether a sentence is passed (checked) or blocked (unchecked). The Sentence and
Divisor fields can be edited by selecting it with the cursor. Edit mode is entered in several ways:
●
Press function key ‘F2’ on your keyboard. This enters Edit mode with the cursor at the end of
the text. Move the cursor around with the mouse or arrow keys.
●
Press Enter or click with the cursor: This enters Edit mode with the text selected and the cursor
at the end. Any character or number that is typed now will erase the existing text entirely
unless the cursor is moved around with the mouse or arrow keys. This will unselect the text.
●
Double-click on the entry. This enters Edit mode the same way as pressing Enter or clicking it
for the second time.
25
When changes are made, press Enter to confirm them or press Escape to discard any changes and
exit Edit mode.
The Technical Reference section lists all commonly used Talker IDs and Sentence Formatters. This
list can be a useful aid while setting up the sentence filter.
The following buttons are available to edit the list:
Store List
Stores the list from MPX-Config into the multiplexer. This overwrites the list in the
multiplexer.
Capture
Enables capture mode. The list will be filled automatically with NMEA sentences
that are received by the multiplexer.
Add
Add a new rule. Type the desired sentence address into the edit box next to the
Add button and click on Add or press the enter key. This will enter a new rule
with all inputs disabled and all outputs enabled. The input is case-insensitive;
every entered sentence address will be converted into uppercase. The input must
contain 5 characters, including dashes. Numbers are also allowed.
Delete
Delete a rule from the list in MPX-Config. Select the entry to be deleted by clicking
on the address in the Sentence column (‘--GLL’ in the example) and click on the
Delete button.
Default Action This determines what happens when a received sentence is not found in the
filter/routing list. It can be set to pass or block such a sentence.
Clear List
This button clears the list in MPX-Config (not in the multiplexer!). To clear the list
in the multiplexer, click on the Store button after clearing the list in MPX-Config.
Filling the list
The filter rules can be entered in two ways, manually and automatically. You can add individual
sentences to the list and set the desired routing information. You can also fill the list automatically
with the Capture button. All controls will be disabled during capture and the Capture button
changes to Stop. Leave the capture mode running for approximately 10 seconds. By that time, all
connected instruments will have sent NMEA sentences. Click on Stop to end the capture mode.
It is very important to realize that using capture to fill the list overrides the default routes since
every sentence is in the filter list. It is therefore absolutely necessary to review and modify the
routing settings for each sentence to prevent massive buffer overflows! It is often best not to use
the filter at all if you don’t need sentence-specific routing. Use the filter with care!
Operation
When the multiplexer receives an NMEA sentence, it searches the filter list for a match. The order
of filter rules in the multiplexer is exactly the same as shown in MPX-Config. When a match is
found, the input on which the sentence was received is checked against the input settings in this
rule to determine whether the sentence may be passed or not. If the input matches, the sentence
is routed to the outputs that are enabled.
If no match is found, the Default Action determines what happens next: when set to Pass, the
received sentence is passed and the default routes are applied. When it is set to Block, the
sentence is blocked.
The default routes are set in the Input Settings section on the NMEA Inputs/Outputs page.
Please note that the multiplexer will not pass any sentence when the filter list is empty and the
Default Action is set to Block.
It is important to know that when a Talker ID is set for an input, it is applied to incoming NMEA
sentences before the sentence filter processes them. A filter rule must therefore contain the right
Talker ID.
26
Example
The example below shows a small set of filter rules:
These rules have the following effect: the GPRMC sentence is passed when it is received on In 1
while the other inputs are blocked. The sentence is routed to Out1 and to the PC (USB port).
The HCHDT sentence is passed from In 2 and routed to the PC. The sentence rate is divided by 5,
which means that only every 5th sentence is passed.
The sentences IIMWV and IIMTW are passed from input 3 and routed to the PC.
The VHVHW sentence is passed only as the result from a conversion (VTG -> VHW) and thus
passed from “In C” to Out1 and the PC.
None of the sentences are sent to the wireless interface (W) and the filter block sentences that are
not in the filter list.
Resetting the multiplexer
The multiplexer can be reset to its default factory configuration by entering ‘PSMDRESET,1’ in the
Manual NMEA Sentence Input and clicking on the Send button.
27
Firmware Update
From time to time, we will develop new features for the multiplexer or fix bugs in the existing
firmware. New firmware image files will then be made available through our website. These image
files can be downloaded to your computer and loaded into the multiplexer with the option Update
Firmware from the File menu.
In order to perform an update, download a firmware image file from our website
www.shipmodul.com and store it on your computer. Connect your computer to the USB port of the
MiniPlex.
You can only update the MiniPlex-2Wi using the USB port!
The update process resets the multiplexer, which results in a lost WiFi connection. Therefore
updating over the WiFi interface is not supported.
Choose Update Firmware from the File menu.
A file dialog opens which allows you to select the previously downloaded image file ending at an
‘.mpx’ extension. When you have selected the file and clicked on OK, the update process is started.
The image file’s integrity and version is checked first before initiating the download procedure in
the multiplexer.
When the download is started, the red LED on the multiplexer will be lit continuously while the
green LED blinks on reception of data from the computer. MPX-Config will show a progress
indicator during the update process. When the update is complete and successful, a message will
show ‘The firmware update was successful’.
Any errors that occur during the process will be shown. It is important to make a note of the error
message when asking for support. See the Technical Reference section for an explanation of the
error messages.
Mounting
The multiplexer is not waterproof. It should be mounted at a dry place, like behind the instrument
panel, on a flat surface.
28
Technical Reference
NMEA Glossary
This glossary lists the most common Talker ID’s and Sentence Formatters in alphabetical order.
Talker ID’s
AG
AP
AI
CD
CR
CS
CT
CV
CX
DE
DF
EC
EI
EP
ER
GP
GL
GN
HC
HE
HN
II
IN
LC
P
RA
SD
SN
SS
TI
VD
VM
VW
VR
YX
ZA
ZC
ZQ
ZV
WI
Autopilot (general)
Autopilot (magnetic)
Automatic Identification System
Communications: Digital Selective Calling (DSC)
Data receiver
Satellite
Radio telephone (MF/HF)
Radio telephone (VHF)
Scanning receiver
Decca navigator
Direction finder
Electronic chart systems (ECS)
Electronic chart display and information system (ECDIS)
Emergency position indicating radio beacon (EPIRB)
Engine room monitoring systems
Global Positioning System (GPS)
GLONASS receiver
Global navigation satellite system (GNSS)
Heading sensors: compass, magnetic
gyro, north seeking
gyro, non-north seeking
Integrated instrumentation
Integrated navigation
Loran, Loran-C
Proprietary sentence
Radar and/or radar plotting
Sounder, depth
Electronic positioning system, other/general
Sounder, scanning
Turn rate indicator
Velocity sensors: doppler, other/general
speed log, water, magnetic
speed log, water, mechanical
Voyage data recorder
Transducer
Timekeepers:
atomic clock
chronometer
quartz
radio updated
Weather instruments
Sentence formatters
AAM
ACK
ALM
ALR
APB
BEC
BOD
BWC
BWR
BWW
DBT
DCN
DPT
DSC
DSE
DSI
DSR
DTM
Waypoint arrival alarm
Acknowledgement alarm
GPS almanac data
Set alarm state
Heading/track controller (Autopilot) sentence B
Bearing and distance to waypoint, dead reckoning
Bearing, origin to destination
Bearing and distance to waypoint
Bearing and distance to waypoint, rhumb line
Bearing, waypoint to waypoint
Depth below transducer
DECCA position
Depth
Digital selective calling information
Expanded digital selective calling
DSC transponder initialise
DSC transponder response
Datum reference
29
FSI
GBS
GGA
GLC
GLL
GNS
GRS
GSA
GST
GSV
HDG
HDT
HMR
HMS
HSC
HTC
HTD
LCD
MLA
MSK
MSS
MTW
MWD
MWV
OSD
RMA
RMB
RMC
ROT
RPM
RSA
RSD
RTE
SFI
STN
TLB
TLL
TTM
TXT
VBW
VDM
VDO
VDR
VHW
VLW
VPW
VTG
WCV
WNC
WPL
XDR
XTE
XTR
ZDA
ZDL
ZFO
ZTG
Frequency set information
GNSS Satellite fault detection
Global positioning system fix data
Geographic position, LORAN-C
Geographic position, latitude/longitude
GNSS fix data
GNSS range residuals
GNSS DOP and active satellites
GNSS pseudo range error statistics
GNSS satellites in view
Heading, deviation and variation
Heading, true
Heading monitor – receive
Heading monitor – set
Heading steering command
Heading/track control command
Heading/track control data
LORAN-C signal data
Glonass almanac data
MSK receiver interface
MSK receiver signal status
Water temperature
Wind direction and speed
Wind speed and angle
Own ship data
Recommended minimum specific LORAN-C data
Recommended minimum navigation information
Recommended minimum specific GNSS data
Rate of turn
Revolutions
Rudder sensor angle
Radar system data
Routes
Scanning frequency information
Multiple data ID
Target label
Target latitude and longitude
Tracked target message
Text transmission
Dual ground/water speed
AIS data message
AIS data, own vessel report
Set and drift
Water speed and heading
Distance travelled through the water
Speed, measured parallel to wind
Course over ground and ground speed
Waypoint closure velocity
Distance, waypoint to waypoint
Waypoint location
Transducer measurements
Cross-track error, measured
Cross-track error, dead reckoning
Time and date
Time and distance to variable point
UTC and time from origin waypoint
UTC and time to destination waypoint
30
Translated SeaTalk datagrams
When the SeaTalk translation is enabled, the following datagrams are translated into NMEA
sentences:
SeaTalk
00
10
11
20
NMEA
DBT
MWV
MWV
VHW
21
22
23
25
26
VLW
VLW
MTW
VLW
VHW
27
50
51
52
53
MTW
------RMC
54
56
58
89
99
------HDG
---
Description
Depth below transducer
Wind angle, (10 and 11 combined)
Wind speed, (10 and 11 combined)
Speed through water, includes heading when
present
Trip mileage (21 and 22 combined)
Total mileage (21 and 22 combined)
Water temperature
Total and Trip mileage
Speed through water, includes heading when
present
Water temperature
GPS latitude, value stored
GPS longitude, value stored
GPS speed over ground, value stored
Course over ground. RMC sentence is
generated from stored values from other GPS
related datagrams.
GPS time, value stored
GPS date, value stored
GPS lat/long, values stored
Magnetic heading, including variation (99)
Magnetic variation, value stored
The table shows that not all datagrams result in an NMEA sentence. Some datagrams are only used
to retrieve data, which is combined with data from other datagrams to be able to create one NMEA
sentence.
When the SeaTalk translation is enabled with option 2 (the ‘s’ parameter in the CF sentence is 2),
unlisted datagrams are translated into a proprietary NMEA sentence with the following format:
$PSMDST,aa,bb,cc,dd…*hh<CR><LF>
aa,bb,cc,dd… represent the hexadecimal value of the bytes from the received SeaTalk datagram.
31
Firmware Update Error messages
During a firmware update, the following warnings or error messages may be displayed:
The firmware update failed
This message appears when the overall update process failed without any other error message.
It is shown when the updated multiplexer firmware does not report a version message after
start-up.
Not a valid firmware file
The file you are trying to open is not a valid firmware file. A firmware file not only ends with an
‘.mpx’ extension, it also contains a distinct signature that must be present. This prevents you
from accidentally loading the wrong file into the multiplexer.
Unsupported firmware file version
The firmware file version is not supported by MPX-Config. Currently, there is only one firmware
file version but it is not unlikely that in the future new version are developed which require an
update of MPX-Config.
Firmware file is corrupt
The firmware file is damaged, possible due to an error during download from our website.
The version of the firmware file is lower than the version of the multiplexer. Do you
really want to proceed?
You are trying to update the firmware in the multiplexer with an older version. This is just a
warning and very well possible to do.
Bootloader initialisation failed
When MPX-Config starts the update process, a small program called the Bootloader must be
started in the multiplexer. This message tells you that the bootloader could not be started. This
can happen when you try to update the multiplexer while navigation instruments are connected
and sending lots of NMEA data to the multiplexer. This can interfere with starting the update
process. Disconnect or power down the instruments to prevent this problem.
Firmware file does not match with the multiplexer type
Most firmware files will be compatible with all types of multiplexers. It is however possible that
special firmware is made available that only runs on a specific type of multiplexer. If this
message appears, you apparently are trying to update using a firmware file that is not suitable
for your type of multiplexer.
Bootloader: Erase command timeout
An error occurred when the bootloader tried to erase the old firmware.
Bootloader: Encryption command timeout
The bootloader did not respond to the Encryption command sent by MPX-Config.
Bootloader: Programming timeout
There was an error during programming a section of the firmware image.
Bootloader: CRC command timeout
The bootloader failed to calculate the checksum of the newly loaded firmware image.
Bootloader: CRC error
The calculated checksum of the newly loader firmware image does not match the checksum if
the image file. Apparently there was a communication error between MPX-Config and the
multiplexer. You can try to update again.
Invalid response from bootloader
The bootloader returned an unknown response to a command from MPX-Config.
32
MPX-Config INI file format
The configuration file format of MPX-Config resembles the standard Windows INI file format and is
readable text. Below is an example of the configuration file. This example corresponds with the
settings shown on the various MPX-Config screenshots throughout this manual.
[Information]
MPX-Config=MiniPlex Configuration Tool V3.9.0
Device=MiniPlex-2Wi
Firmware Version=3.17.1
Serial Number=25002391
[Configuration]
Baud In1=3
Baud In2=1
Baud In3=0
Baud In4/Out1=0
Baud Out2=3
SeaTalk=1
Priority=1
Priority Timeout=3
Channel Numbers=0
RealTime Ch.1=0
RealTime Ch.2=0
RealTime Ch.3=0
RealTime Ch.4=0
RealTime Conv=0
HDG Translation=0
VTG Translation=1
HDT Reverse=0
Talker ID1=
Talker ID2=
Talker ID3=WI
Talker ID4=
Talker IDConv=
Route 11=0
Route 21=0
Route 31=0
Route 41=0
Route Conv1=0
Route 12=1
Route 22=1
Route 32=1
Route 42=1
Route Conv2=1
Mode Out1=1
Mode Out2=0
Filter Mode=1
[Filter]
GPRMC=010000,0,1010
HCHDT=001000,5,0010
IIMWV=000100,0,0010
IIMTW=000100,0,0010
VHVHW=000001,0,1010
33
Proprietary NMEA Sentences
The MiniPlex multiplexers are configured with proprietary NMEA sentences that can be sent to the
multiplexer through the host interface.
The multiplexer can also output proprietary NMEA sentences on a host interface to output status
information or a response to a received proprietary NMEA sentence.
The host interface is the port that connects to a computer, laptop, smartphone or tablet by means
of RS-232, USB, Bluetooth, WiFi or Ethernet. A MiniPlex can have more than one host interface.
When the multiplexer outputs something on a host interface, it is sent to all host interfaces
simultaneously. All host interfaces operate equally and have equal priority.
All MiniPlex proprietary sentences have the following format:
$PSMDxx[,a,b,…][*hh]<CR><LF>
$P:
SMD:
xx:
a,b,…:
hh:
<CR><LF>:
Start of a proprietary command as dictated by the NMEA standard
ShipModul manufacturer mnemonic
Two- or three-character sentence formatter
Optional fields
Optional checksum
Carriage Return and Line Feed characters that terminate the sentence
By default, fields are optional and may be skipped when no change is required. For instance, a
$PSMDCF,,,,1 sentence only enables Channel Numbers. The preceding fields are skipped (,,,,) and
the trailing fields are omitted.
For ease of manual configuration, these sentences do not require a checksum. If the sentence has
a checksum however, it is checked and the sentence is rejected when a checksum failure occurs.
Sentences output by the multiplexer always contain a checksum unless the checksum check is
switched off. Checksums are denoted with *hh in the descriptions below.
CF – Configuration
This sentence sets the configuration of the multiplexer. The same sentence is sent by the
multiplexer in response to a CFQ sentence.
Format: $PSMDCF,b,s,p,n,rrrrr,h,v,t,f,r[*hh]<CR><LF>
1)
b:
Baud rate selector for the RS-232 interface:
0 = 4800 Baud
1 = 9600 Baud
2 = 19200 Baud
3 = 38400 Baud
4 = 57600 Baud
5 = 115200 Baud
9 = toggle checksum checking 2)
s:
SeaTalk translation:
0 = off
1 = on
2 = dump all unknown SeaTalk datagrams ($PSMDST,xx,xx,…)
3 = dump all SeaTalk datagrams
4 = toggle generated wind sentence between VWR and MWV
p:
Channel priority:
0 = off
1 = on, standard priority order
3 = on, SeaTalk has highest priority
5 = on, standard priority order, GPS status checked
7 = on, SeaTalk has highest priority, GPS status checked
n:
Channel numbers:
0 = off
1 = send as NMEA sentence
2 = send a TAG block
rrrrr:
Real-time mode:
0 = off
1 = on
Five digits, one digit per input, 1 to 5 from left to right. Input 5 is the source of internally
generated sentences from NMEA conversions.
34
h:
Heading translation:
0 = off
1 = on
v:
Velocity translation:
0 = off
1 = on
t:
Priority Timeout (in seconds):
0=1
1=2
2=3
3=5
4 = 10
5 = 30
f:
Filter mode:
0 = Pass sentences that are not present in the filter list
1 = Block sentences that are not present in the filter list
r:
Reverse heading. When enabled (1), a new HDT sentence is generated from an incoming
HDT sentence with the heading reversed by 180 degrees. Use the Sentence Filter to route
the original and new HDT sentences to different outputs.
The ‘s’ field will always return a 0 or 1 in response to a CFQ sentence.
1) The speed setting is ignored on multiplexers without RS-232 serial interface.
2) By default, the multiplexer checks the checksum of every incoming sentence. When a
checksum error is found, the sentence is rejected. This check can be enabled or disabled with
$PSMDCF,9. When the check is disabled, the multiplexer passes sentences with a checksum
error unprocessed.
The response of the CFQ sentence shows whether the check is enabled or disabled: when the
CF response has a checksum, it is enabled. Note that $PSMDCF,9 is a toggle that enables or
disables the checksum check. It does not change the baud rate and a CF response will always
show the normal baud rate setting (No. 0..3).
CFQ – Request current configuration
This sentence requests the current configuration settings from the multiplexer.
Format: $PSMDCFQ[*hh]<CR><LF>
The multiplexer responds with a CF sentence. When the response contains a checksum, the
checksum checking is enabled and the multiplexer rejects sentences with a checksum error. When
the CF response shows no checksum, the multiplexer passes sentences that contain a checksum
error.
CN - Channel Number indicator
This is sentence is output by the multiplexer when Channel Numbers are enabled with the CF
sentence (n = 1). It precedes an NMEA sentence on the host interface to indicate through which
input channel the sentence was received.
Format: $PSMDCN,x*hh<CR><LF>
x:
Channel number 1,2,3 or 4
DR – Default Route
This sentence specifies the default route from the NMEA inputs to the NMEA outputs and from the
host interface to the NMEA outputs. Any route set by the FL sentence overrides the standard route.
Format: $PSMDDR,xxxxx,a,yyyyy,b[*hh]<CR><LF>
xxxxx:
Input field for NMEA Out1. Each ‘x’ represents an input, numbered from 1 to 5 from left to
right. Input 5 is not a real input but the source of NMEA sentences generated from
conversions. When ‘1’, the input is routed to output 1. When ‘0’, the input is not routed to
output 1.
a:
Host data to NMEA Out1:
0: Host data is not routed
1: Host data is routed
2: Host data is routed and overrides data from the inputs. A time out mechanism
route data from the inputs when no data from the host is received.
35
will
yyyyy:
Input field for NMEA Out2. Each ‘y’ represents an input, numbered from 1 to 4 from left to
right. Input 5 is not a real input but the source of NMEA sentences generated from
conversions. When ‘1’, the input is routed to output 2. When ‘0’, the input is not routed to
output 2.
b:
Host data to NMEA Out2:
0: Host data is not routed
1: Host data is routed
2: Host data is routed and overrides data from the inputs. A time out mechanism
will route data from the inputs when no data from the host is received.
DRQ – Request Default Route
Requests the default route settings. The multiplexer responds with a DR sentence.
Format: $PSMDDRQ[*hh]<CR><LF>
FL – Filter
This sentence specifies a filter and routing rule that is applied on every incoming NMEA sentence.
Filter rules are specified using the address field of an NMEA sentence. For each filter rule, the
inputs on which the sentence may be received must be specified. Optionally, a divisor and an
output routing field can be added.
Sentences for which no rule exists are passed or blocked, depending on the filter mode set by field
‘f’ of the CF sentence.
Format: $PSMDFL,ccccc,xxxxx[,dd][yyyy][*hh]<CR><LF>
ccccc:
Address field of the filter rule (e.g. ‘GPRMC’, ‘IIMWV’, etc). This field may contain wildcard
characters (‘-’). For instance, ‘GP---’ will apply to all sentences starting with ‘GP’.
Similarly, ‘--MWV’ will apply to all sentences ending on ‘MWV’ regardless of the Talker ID.
One filter rule with all wildcards and all inputs blocked is allowed to let the multiplexer
block all sentences for which no rule exists. When an all-wildcard rule is entered, the
multiplexer will not accept subsequent filter rules.
Example: $PSMDFL,-----,00000<CR><LF>
xxxxxx: Input field. Each ‘x’ represents an input to assign to this rule, numbered from 0 to 5 from
left to right. Input 0 is the host interface and inputs 1 to 4 represent NMEA inputs 1 to 4.
Input 5 is not a real input but the source of NMEA sentences generated from conversions.
A ‘1’ means that the sentence must be forwarded while a ‘0’ means that the sentence
must be blocked from that input.
dd:
Optional divisor factor (0..99). The rate or frequency of a sentence is divided by this
number to reduce the number of sentences over time. If for instance a divisor of 6 is
specified, only every 6th occurrence of this sentence is passed.
yyyy:
Optional routing field. Each ‘y’ represents an output the NMEA sentence must be routed
to. A ‘1’ routes the sentence to an output, a ‘0’ does not. Each digit represents one
output. From left to right, the outputs are NMEA Out1, NMEA Out2, Host and Wireless
interface.
When this field is omitted, a default of ‘1111’ is assumed, routing the specified sentence
to all outputs.
hh:
Optional checksum
An FL sentence with the word DELETE in the ‘ccccc’ field erases all rules. An FL sentence with only
a ‘ccccc’ field will erase that entry. The filter accepts duplicate entries with the same ‘ccccc’ field to
allow separate routes from inputs to outputs.
Example: $PSMDFL,HEHDT,000110,5,1010<CR><LF>
This sentence specifies a rule for all sentences that have ‘HEHDT’ in the address field. It only
passes HEHDT sentences from inputs 3 and 4, the rate is lowered by a factor of 5 and the
sentence is routed to NMEA Out1 and the host only.
36
FLQ – Request Filter List
This sentence requests the filter list from the multiplexer. The multiplexer responds by sending FL
sentences, one for each list entry. An empty FL sentence marks the end of the list.
Format: $PSMDFLQ[*hh]<CR><LF>
Example response:
$PSMDFL,GPRMC,100110,0,1111*4A<CR><LF>
$PSMDFL,GPGGA,100010,0,1111*56<CR><LF>
$PSMDFL,--VWT,010000,5,0001*50<CR><LF>
$PSMDFL,GPGSV,000010,0,0010*55<CR><LF>
$PSMDFL,*2C<CR><LF>
The sentences may not be dumped as one contiguous block. In case of much NMEA data, they may
be interspersed with other NMEA sentences.
ID – Talker ID
This sentence sets a Talker ID translation for a specific input. If a Talker ID is set, the original
Talker ID of the sentences received on that input is replaced by the specified one, before sending
the sentence to the host.
Format: $PSMDID,aa,bb,cc,dd,ee[*hh]<CR><LF>
aa:
bb:
cc:
dd:
ee:
hh:
Talker ID for channel 1
Talker ID for channel 2
Talker ID for channel 3
Talker ID for channel 4
Talker ID for internally generated sentences
optional checksum
An empty field clears the ID and disables the translation for that specific channel. Sending PSMDID
without any fields clears all translations.
IDQ – Request Talker ID’s
Requests the Talker ID translation settings. The multiplexer responds with an ID sentence.
Format: $PSMDIDQ[*hh]<CR><LF>
LDR – Loader message
This sentence is output by the bootloader on the host interface. It contains the loader version and
multiplexer ID. The loader will wait for a special key during 0.2s after sending this sentence. When
no key is received, the multiplexer application code is started. If no application code is found, the
loader will continue sending this sentence.
Format: $PSMDLDR,xx,v.v,zzz
xx:
v.v:
zzz:
Hardware ID of the multiplexer (a hexadecimal number)
Bootloader version number
Hardware name of the multiplexer
The following hardware ID’s and names are defined:
01:
02:
03:
04:
MPX-S
MPX-U
MPX-E
MPX-W
(board
(board
(board
(board
with
with
with
with
RS-232 interface)
USB interface)
Ethernet interface)
USB and WiFi interface)
When bit 7 of the hardware ID is set, e.g. 81, the board has a Bluetooth module installed.
Example: $PSMDLDR,82,1.2,MPX-U
This multiplexer has a MPX-U board with a USB interface and a Bluetooth module installed and
the bootloader is version 1.2.
OV – Overflow
In case of a queue overflow (blinking red LED on the multiplexer), an overflow sentence is output
on the host interface, to indicate on which input queue the overflow occurred:
Format: $PSMDOV,x*hh<CR><LF>
x:
Binary field. The first four bits indicate on which input queue the overflow occurred.
37
RESET – Reset the multiplexer
This sentence resets the multiplexer and starts the bootloader. When a ‘1’ is given as parameter,
the factory settings of the multiplexer are restored.
Format: $PSMDRESET,x[*hh]<CR><LF>
x:
Optional parameter to indicate an action while resetting
1: restore the multiplexer to its factory settings
After a reset, the multiplexer outputs a LDR sentence and a VER sentence on the host interface.
SP – Speed
This sentence sets the baud rate of the NMEA inputs and outputs.
Format: $PSMDSP,a,b,c,d,e,f[*hh]<CR><LF>
The following fields are defined for setting the various inputs and outputs:
a:
b:
c:
d:
e:
f:
NMEA In 1
NMEA In 2
NMEA In 3
NMEA In 4/Out 1
NMEA Out 2
RS-232 host port (ignored on multiplexers without RS-232 host port)
Valid field values are:
0
1
2
3
4
5
=
=
=
=
=
=
4800 Baud
9600 Baud
19200 Baud
38400 Baud
57600 Baud
115200 Baud (field e and f only)
Field ‘d’ is ignored when SeaTalk translation is enabled with the CF sentence.
SPQ – Request Speed
Request the baud rate settings of the NMEA inputs and outputs.
Format: $PSMDSPQ[*hh]<CR><LF>
The multiplexer responds with an SP sentence.
TAG Block
When the Channel Numbers option is set to ‘2’ (field ‘n’ of the CF sentence), the multiplexer adds a
TAG block to every NMEA sentence that is output on the host interface. This TAG block has one
source parameter, indicating the input that sentence was received on. It has the following format:
\s:mchx*hh\
where ‘x’ is a digit from 1 to 4, representing the input number. A heading sentence received on
input 1 will be sent to the host as
\s:mch1*1E\$HEHDT,23.5*37<CR><LF>
38
VER – Get Version
This sentence retrieves version information from the multiplexer.
Format: $PSMDVER
The multiplexer responds with the following version sentence:
$PSMDVER,3.17.1,MiniPlex-2S,10025943,8040*hh<CR><LF>
3.17.1:
firmware version number
MiniPlex-2S: multiplexer name
10025943:
serial number
8040:
Multiplexer capabilities. This is a 4 digit, 16-bit field represented as a hexadecimal
number. Each bit identifies a capability of the multiplexer. The following bits are
defined:
1-0:
Host interface type, 0 = serial, 1 = USB, 2 = Ethernet, 3 = USB & WiFi
2:
Bluetooth module installed
6:
Firmware update supported
15:
3rd generation multiplexer
hh:
checksum
WI – Wireless control
This sentence controls the wireless module on the multiplexer (WiFi or Bluetooth). This sentence
always results in a response sentence from the multiplexer. This response reflects the response of
the wireless module or the result of the operation.
Format: $PSMDWI,x[,a,b..][*hh]<CR><LF
x:
Sub-command. See below
a,b..: Optional parameters required by a subcommand
Response: $PSMDWI,message
The following sub-commands are defined:
0..6: Set the baud rate of communication port of the multiplexer that is connected to the wireless
module. A single digit in the range of ‘0’ to ‘6’ sets the speed according to the table below:
0: 4800 Bd
1: 9600 Bd
2: 19200 Bd
3: 38400 Bd
4: 57600 Bd
5: 115200 Bd
6: 230400 Bd
This command is used to be able to talk to an un-initialized module at its default speeds of
9600 Bd (value ‘1’) or when a firmware update requires a new speed setting.
This speed setting is temporary: after a power cycle the speed is reset to its normal
operational value, determined by the firmware of the multiplexer.
A:
Configure the WiFi module with the multiplexer default access point settings:
SSID:
Channel:
IP address:
Network mask:
TCP port:
MiniPlex-2Wi:xx:yy
1
10.0.0.1
255.255.255.0
10110
xx:yy are the last two bytes of the MAC address of the WiFi module.
B:
Configure the Bluetooth module with the multiplexer default settings
C:
Set the wireless module to Command Mode. This enables sending of commands directly to
the wireless module using the $PSMDWI sentence. See section Command Mode for more
details. Sending $PSMDWI without any parameters exits Command Mode.
When command mode is enabled, all NMEA data from In1..4 is blocked.
E:
Erase the trusted (paired) devices list in the Bluetooth module.
M:
Return the MAC address of the wireless module.
39
N:
Set the network parameters of the WiFi connection:
$PSMDWI,N,ip,mask,gw[*hh]<CR><LF>
ip:
IP address, 0 for automatic assignment by a DHCP server
mask: network mask
gw:
optional gateway address
$PSMDWI,N,0 sets the multiplexer to DCHP in order to obtain all settings automatically.
The gateway address is only needed to obtain firmware updates of the WiFi module. When
the ip field contains a ‘0’, the IP settings will be obtained from a DHCP server and all other
fields will be ignored. Fields may be omitted for parameters that need no change. For
instance: $PSMDWI,N,,,192.168.1.1 only sets the gateway address.
T:
Set the multiplexer to Terminal Mode. This opens a direct communication channel from the
wired host interface to the wireless module. A terminal program can then be used to
communicate directly with the wireless module. The multiplexer can be set to normal (NMEA)
mode by a power cycle or by typing a ctrl-q character. See section Terminal Mode for more
details
In Terminal Mode, the multiplexer does not respond to any proprietary NMEA commands, nor
will it operate as a multiplexer.
U:
Update the firmware in the WiFi module. Before using this command, the multiplexer must
be configured to connect to an existing access point with a connection to the Internet. This
can be accomplished with the W and the N sub-commands.
V:
Return the version number of the WiFi firmware. A $PSMDWI,x.xx sentence is returned.
W:
Set the WLAN parameters of the WiFi connection:
$PSMDWI,W,mode,ssid,[phrase][*hh]<CR><LF>
mode:
ssid:
phrase:
A = Access Point, I = Infrastructure
SSID of the WiFi connection
Optional pass phrase (only for Infrastructure mode)
When Access Point mode is set, the radio channel is set to 1 and the IP address/netmask are
set to 10.0.0.1/255.255.255.0. They may be changed with the ‘N’ sub-command.
When Infrastructure mode is set, the radio channel is selected automatically and DHCP is
enabled. The previously stored IP address/netmask are retained in case the multiplexer does
not receive these from a DHCP server or access point.
Z:
Configure the WiFi module for production testing
If any of the above commands fails, the wireless module may still be in Command Mode, indicated
by a $PSMDWC response instead of $PSMDWI. To switch the multiplexer back to normal, a
$PSMDWI sentence must be issued without any parameters.
Command Mode
The sub commands listed above are used to change the most common settings of the wireless
module by means of an NMEA sentence. The PSMDWI,A sentence for instance, sets over 25
parameters in the WiFi module automatically. In some cases, it is necessary to fine tune individual
settings of the wireless module. Command Mode allows sending special commands to the module
using an NMEA sentence. For instance, if you would need to change the MTU value of the WiFi
connection, you can use the following sentences to do this:
$PSMDWI,C
$PSMDWI,set ip mtu 600
$PSMDWI
(enter command mode)
(set the MTU value to 600)
(exit command mode)
The second sentence sends the command ‘set ip mtu 600’ to the WiFi module.
The general format of a direct command sentence is:
$PSMDWI,command,[response],[time out][*hh]<CR><LF
command:
[response]:
[time out]:
command to be sent to the wireless module.
optional expected response.
optional time out value of 1..9 seconds. Standard time out is 1 second.
If an optional expected response is specified, the multiplexer returns either of two sentences:
$PSMDWC,OK
$PSMDWC,No Response
(the module returned the expected response)
(the expected response was not received)
40
If no expected response is specified, the multiplexer returns
$PSMDWC,message
where message is the response from the module.
The module-specific commands are not listed here because they fall outside the scope of this
specification.
Note that the multiplexer responds with a $PSMDWC sentence when it is in command mode. In
normal mode, a $PSMDWI response is given. A PSMDWI sentence without any parameters exits
command mode. When this sentence is issued in normal mode, a $PSMDWI,No response is
returned.
Terminal Mode
Terminal Mode creates a direct connection between the wired and the wireless interface for testing
and debugging purposes. All other inputs and outputs of the multiplexer are inactive.
A $PSMDWI,T sentence enables Terminal Mode with the wireless module in Data mode. The
blinking red LED indicates Terminal Mode.
At this point, a direct connection exists and no NMEA commands are recognised by the multiplexer.
The connection is completely transparent and any (NMEA) data is passed in both ways. Three
control codes are implemented to control Terminal Mode:
Ctrl-q: Exit Terminal Mode. The wireless module will be set to Data mode and the multiplexer
returns to normal operation. The red LED is off.
Ctrl-c: Switch the wireless module to command mode, to control the configuration of the module
through the wired interface.
Ctrl-d: Switch the wireless module to data mode.
Cycling the power of the multiplexer also exits Terminal Mode.
41
Technical Specifications
Supply voltage:
8 – 35 VDC, protected against reversed polarity.
Current consumption:
70 mA (130 mA max. with fully loaded talker ports).
Host interface:
WiFi (802.11b/g, +18dBm)
USB, galvanically isolated.
NMEA Inputs:
4 x NMEA 0183/RS-422, galvanically isolated. Input 4 can be set
to SeaTalk mode.
Input resistance:
>800 Ohm.
NMEA Outputs:
2 x NMEA 0183/RS-422.
Output drive capacity:
4 NMEA inputs.
Queues:
6 queues of 1024 characters (4 x NMEA, 1 x USB, 1 x WiFi).
Filter list size:
50 sentence types
Priority list size:
50 sentence types
Speed NMEA In 1-3:
4800 - 57600 Baud.
Speed NMEA In 4/Out 1:
4800 - 57600 Baud.
Speed NMEA Out 2:
4800 - 115200 Baud.
Indicators:
Overflow, Data and WiFi connection.
Dimensions:
138 x 72 x 33 mm.
Housing:
Flame retardant ABS.
42
Declaration of Conformity
We,
CustomWare
Borgstee 27b
9403 TS Assen
The Netherlands
Tel.: +31 592 375700
Fax: +31 592 375550
Declare under our sole responsibility that the product
ShipModul MiniPlex-2Wi
to which this declaration relates is in conformity with the following specifications:
EN/IEC61000-6-1:1997 and EN/IEC61000-6-3:1996
EN/IEC61162-1:2000
EN/IEC300328:2006
EN/IEC301489-1:2008
EN/IEC301489-17:2008
FCC Title 47 CFR, Part 15 Class B, FCC ID: U30-G2M5477
IC: RSS-210
The product herewith complies with the requirements of the EMC Directive 89/336/EEC and carries
the CE-marking accordingly.
Assen, 1-1-2011
M. Sprang
This device complies with Part 15 of the FCC Rules. Operation is subject to the following conditions:
(1) This device may not cause harmful interference, and (2) this device must accept any
interference received, including interference that may cause undesired operation.
0681
43
ShipModul / CustomWare
Borgstee 27b
9403 TS Assen
The Netherlands
web: www.shipmodul.com
e-mail: support@shipmodul.com
44
Download PDF