ADC O N

T E L E M E T R Y

Base Station

Telemetry Gateway A840 and

Wireless Modem A440

User Guide

SMART WIRELESS SOLUTIONS

ADC O N

T E L E M E T R Y

ADCON TELEMETRY AG

I N K U S T R A S S E 2 4

A-3400 KLOSTERNEUBURG

A U S T R I A

TEL: +43 (2243) 38 280-0

FAX: +43 (2243) 38 280-6 h t t p : / / w w w . a d c o n . a t

ADCON TELEMETRY INC

1 0 0 1 YA M A T O R O A D

SUITE #305, BOCA RATON

F L 3 3 4 3 1 U S A

TEL: +1 (561) 989-5309

FAX: +1 (561) 989-5310 h t t p : / / w w w. a d c o n . c o m

A D C O N T E L E M E T RY S R L

BD. ION IONESCU DELABRAD 8

R - 7 1 5 9 2 B U C H A R E S T

R O M A N I A

T E L : + 4 0 ( 1 ) 4 9 0 - 6 0 8 3

FA X : + 4 0 ( 1 ) 4 9 0 - 6 0 8 6 h t t p : / / w w w . a d c o n . r o

Proprietary Notice:

The Adcon logo, the A720 and A730 series, addIT™, addWAVE™, the A840 series and Telemetry Gateway, addVANTAGE®, and addVANTAGE Lite are trademarks or registered trademarks of

Adcon Telemetry. All other registered names used throughout this publication are trademarks of their respective owners.

Neither the whole nor any part of the information contained in this publication may be reproduced in any material form except with the prior written permission of Adcon Telemetry.

This publication is intended only to assist the reader in the use of the product. Adcon Telemetry shall not be liable for any loss or damage arising from the use of any information in this publication, or any error or omission in such information, or any incorrect use of the product.

Document Release 1.2, September 2001

Copyright ©2001 by Adcon Telemetry.

All rights reserved.

Table of Contents

Chapter 1. Introduction _________________________________7

Chapter 2. System Setup ________________________________9

Package Contents _______________________________________9

Installation _____________________________________________9

Installing the Outdoor Unit __________________________ 12

Installing the Indoor Unit ____________________________ 13

Initializing the Base Station __________________________ 14

LED Indicators ________________________________________ 15

Linux Mode ________________________________________ 15

LAN and ACT ___________________________________ 15

USR and RUN ___________________________________ 15

PWR ___________________________________________ 16

Hermit Mode ______________________________________ 16

Chapter 3. Advanced Functions________________________ 17

Administrative Tasks at the System Level _________________ 17

Stopping and Starting the telemetry gateway __________ 18

3

4

Changing Passwords ________________________________ 19

Losing a Password __________________________________ 20

Software Upgrades__________________________________ 21

Upgrading the bootloader ________________________ 21

To upgrade the system ___________________________ 22

Operations at the Application Level ______________________ 23

Commands Accepted by the emu3ap Emulator_________ 23

Configuration Commands____________________________ 24

INSERT _________________________________________ 24

REPLACE _______________________________________ 24

DELETE_________________________________________ 24

ROUTE _________________________________________ 25

MASTER ________________________________________ 26

EXTEND ________________________________________ 26

SET Commands__________________________________ 26

SET TIME _______________________________________ 27

SET FREQ_______________________________________ 27

SET OWNID_____________________________________ 28

SET SLOT _______________________________________ 28

SET DELAY______________________________________ 28

SET ECHO/NOECHO ____________________________ 29

Data Commands____________________________________ 29

GETBLOCK _____________________________________ 29

Administrative Commands ___________________________ 31

VER ____________________________________________ 31

TYPE ___________________________________________ 31

INSPECT________________________________________ 31

UPTIME_________________________________________ 32

NOP ___________________________________________ 32

HELP ___________________________________________ 32

QUIT ___________________________________________ 32

Direct Radio Commands _____________________________ 32

PING ___________________________________________ 33

REQUEST _______________________________________ 34

RSETIO _________________________________________ 35

PORT___________________________________________ 36

ANALOG _______________________________________ 36

B ______________________________________________ 36

RB _____________________________________________ 37

RBLIST _________________________________________ 37

RSET ___________________________________________ 38

Error Messages_____________________________________ 38

Frame Types _______________________________________ 39

The A730MD frames _____________________________ 39

Type 9__________________________________________ 39

The A720 (addIT) Frames _________________________ 42

Type 38 ________________________________________ 42

The A723 (addIT series 3) Frames__________________ 43

Type 39 ________________________________________ 44

The A733 (addWAVE) Frames _____________________ 45

Type 37 ________________________________________ 46

Frame Parsing Example _____________________________ 48

5

6

Chapter 1. Introduction

7

This manual describes the use of the A840 Telemetry Gateway and

A440 Wireless Modem combination. Due to their general nature, either unit can also be used independently, but such uses are beyond the scope of this manual. The manual teaches you how to use the telemetry gateway and the wireless modem as a base station for an Adcon wireless network.

To build a network, you need one or more A730MD, A733, A720, or A723 remote telemetry units (RTUs), an A840/A440 base station, and the addVANTAGE software. For additional information concerning the RTUs and the addVANTAGE software, consult the respective user manuals.

The A840 Telemetry Gateway is a low-power, battery-backed device that acts as an interface between an Adcon wireless network and one or more hosts running addVANTAGE or similar data acquisition software. The gateway is based on a powerful 32-bit processor running the Linux operating system. It has 16-MB Flash

EPROM acting as a hard disk and 16 MB RAM. The software can be upgraded in the field.

Several interfaces are available: ethernet, V34 modem, RS-232 serial, and RS-485 multidrop serial. A built-in rechargeable battery

8 CHAPTER 1

Introduction provides the telemetry gateway with at least 24 hours of operation without mains power.

The A440 Wireless Modem is a low-power, narrow-band data transceiver operating in the 70-cm band. It implements Adcon’s lowspeed radio protocol and is therefore compatible with all Adcon

RTUs. In addition the A440 modem supports a high-speed wireless protocol that will be used by future Adcon devices.

The A440 has an 8-bit Flash-based microcontroller that can also be upgraded in the field.

NOTE FOR USA: THIS DEVICE COMPLIES WITH PART 15 OF THE

FCC RULES. OPERATION IS SUBJECT TO THE CONDITION THAT

THIS DEVICE DOES NOT CAUSE HARMFUL INTERFERENCE.

Chapter 2. System Setup

9

Package Contents

Before proceeding to the installation of your base station, first verify that you received all of the following components:

• The A840 Telemetry Gateway

• The A440 Wireless Modem

• The 30 m (100 ft) connection cable between the A840 and the

A440 devices

• A power cord

• A twisted-pair ethernet cable (not used at this time, but included in the package)

• A serial null modem cable

• A whip antenna

If any of the above items is missing, contact your dealer.

Installation

The base station has two main components: an indoor unit (the

A840) and an outdoor unit (the A440).

10 CHAPTER 2

System Setup

Before proceeding with the installation, take a moment to plan your network. First, it is essential to realize the importance of selecting a good location for the base station. You must consider several factors, some of them quite contradictory, when you select this location:

• From a radio perspective, the height of the receiving antenna is essential: the higher the antenna, the greater the range of communication.

• The base station should be situated in the same building where the personnel managing the base station work, or at least spend some of their time.

• Places like cellars, near heat sources, or damp locations are not suitable.

• Geographically, it is better to have the base station in the center of the area where the RTUs will be installed.

• If you plan to use the base station as a server to allow other people to log in and get data, you have to make certain that a telephone line is available exclusively for this use.

• A telephone connection next to the PC is also very important for when you need technical support.

The communication distance you can achieve is directly proportional to the height of the receiving antenna. The propagation mode of the waves the Adcon system uses is basically the line of sight. Due to the curvature of the earth, on flat terrain, the maximum distance reached depends on the height of the receiver and of the measuring stations’ antennas. You can’t do much on the remote station side, but you have more options with the base sta-

CHAPTER 2

Installation

11 tion. Some typical examples of the achieved distances, under various conditions, are shown in Table 1.

Table 1. Communication Between Base Station and

A730MD/A733

Receiving antenna height

6 m (18 ft)

10 m (31 ft)

20 m (62 ft)

30 m (92 ft)

Typical distances achieved

5 km (3 miles)

8 km (5 miles)

16 km (10 miles)

24 km (15 miles)

The addIT RTU, however, uses low-power technology and was not designed to communicate over large distances. The typical “lineof sight” distance an addIT can communicate is 800 m (approximately half a mile). This is valid if the partner device is mounted on a 3 m mast (9 ft) and the addIT is mounted on a 30 cm mast (1 ft).

The above figures are estimates based on a great deal of experience with installing this kind of equipment and assume a typical height of 3 m (9 ft) for the antennas of the remote measuring stations. Similarly, ideal physical conditions are assumed for the terrain including a flat, open, nonurban environment.

What conclusions can be drawn from Table 1? Primarily, you can see the importance of having the base station antenna as high as possible. To gain antenna height, you have several options:

• Build a mast directly on the ground; however, a 30 m (100 ft) mast may not be a practical option.

• Set up a mast on a tall building (of course, it has to be the building where you want to have the base station).

• Install the base station in a building that is situated on a hill.

Note that the cable for the outdoor unit delivered with the system is 30 m long (about 100 ft). This means you must locate your indoor unit no more than 30 m from the outdoor unit. Lengthening the cable is not recommended, because the signal strength loss is significant.

12 CHAPTER 2

System Setup

To use the telemetry gateway and wireless modem, you need to do the following:

• Install the outdoor unit.

• Install the indoor unit.

• Initialize the base station.

Installing the Outdoor Unit

Install the outdoor unit on the rooftop of the house where the base station will be located or on top of a nearby mast.

After unpacking the components of the base station, identify the device marked “Wireless Modem A440.” This unit has two connectors: one for a whip antenna (also supplied in the package) and a second that accommodates the 30 m (100 ft) connection cable to the indoor unit.

Note: This operation should be performed by a certified electrician. Make sure that the mast on which the A440 Wireless

Modem will be installed is properly grounded.

Complete the following steps to install the outdoor unit:

1.

Fasten the wireless modem to the aluminum mast (provided by Adcon) using the supplied ring clamp.

2.

Fasten the antenna to the wireless modem.

3.

Plug the proper end of the communication cable into the lower connector of the wireless modem.

4.

Secure the mast in its place on the roof.

5.

Run the cable to the indoor unit.

Figure 1 illustrates these steps.

CHAPTER 2

Installation

13

Figure 1. Outdoor Unit Installation

Note: The cable supplied to connect the outdoor unit to the A840

Telemetry Gateway is 30 m long and cannot be extended.

Extending the cable will make your wireless modem inoperable due to the voltage loss on the additional cable length.

You can, however, install an outdoor antenna and use a coaxial cable (max. 30 m) between the A440 unit and the antenna, giving you a total of 60 m distance between the indoor unit and the outdoor antenna.

Installing the Indoor Unit

First identify the device marked “Telemetry Gateway A840,” which is the indoor unit. Then connect the cables to the gateway as shown in Figure 2.

14 CHAPTER 2

System Setup

Figure 2. Indoor Unit Installation

If you plan to use the base station as a standalone unit (that is, without a computer), you need a telephone line that must be connected to the modem jack of the A840 gateway.

Note: Before you operate the base station, Adcon recommends that you let the internal battery charge to a level where it can sustain the operation of the gateway. You can do this by plugging the power cable into the A840 device, but leaving the serial cable to the A440 outdoor unit disconnected for at least six hours.

Initializing the Base Station

For the base station to operate properly, you must start the addVANTAGE software. Make sure that the software is properly configured (the serial port, and so forth); for additional configuration details, refer to the respective software manual. If your base station operates standalone (as dumb server), initiate a call through addVANTAGE to configure the gateway.

If you are installing the base station as replacement for an A730SD receiver, just upgrade your addVANTAGE installation to version

3.45 or higher (earlier versions don’t support the A840 Telemetry

Gateway). After starting addVANTAGE, your new base station will be configured automatically.

CHAPTER 2

LED Indicators

15

LED Indicators

The A840 Telemetry Gateway has five LED indicators on its panel.

The indicators have a different significance based on whether the device is operating in the usual Linux mode or in hermit mode (for upgrading software and in other unusual circumstances).

“Advanced Functions” on page 17 provides more details about the operating modes.

Linux Mode

If this is a new installation, you need to install the RTUs in the field and configure them in addVANTAGE. Refer to the addVANTAGE software and respective RTU user manuals for additional details.

LAN and ACT

These two LEDs are active only if you have a network cable attached to the gateway and the network section is enabled. In addition, the mains (110/220 volt) must be present, that is, the gateway must not run on its internal batteries. The LAN LED is lit while the ethernet line is operational, and the ACT LED shows activity on the ethernet line.

Note: Although most of the network functionality is already built into your gateway, it is not enabled by default. You must contact Adcon or your distributor if you want to enable networking in your gateway.

USR and RUN

The USR LED lights when communication takes place over the RS-

485 line, that is, to or from the A440 Wireless Modem unit. The

RUN LED is currently not used in Linux mode.

16 CHAPTER 2

System Setup

Hermit Mode

PWR

Table 2 summarizes the PWR LED significance:

Table 2. The PWR LED Indicator

Mains

Present

Not present

PWR LED

ON

ON 15/OFF 1 (2 sec)

ON 8/OFF 8 (2 sec)

ON 1/OFF 15 (2 sec)

Battery unknown

Full

Half full

Almost empty

When the mains is not present, the PWR LED blinks at a 2-second rate. The on/off state of the blink shows you how much power is left in the battery. For example, as you can see in Table 2, if the

LED is lit for most of the two-second period (on 15/off 1), the battery is full. But if the LED is lit only briefly (on 1/off 15), the battery is almost out of power.

In hermit mode (see also “Administrative Tasks at the System

Level” on page 17) only the USR, RUN, and PWR LEDs are significant. Table 3 summarizes their significance.

Table 3. USR, RUN, and PWR LED Indicators

State

Reset/Power On Reset

Hermit 5 sec. wait

Hermit got key

Hermit boots

Hermit failed

USR

ON

OFF

OFF

OFF

OFF

RUN

ON

OFF

OFF

ON

ON

PWR

ON

ON

2 sec ON/2 sec OFF

2 sec ON/2 sec OFF

0.5 sec ON/0.5 sec OFF

Chapter 3. Advanced Functions

17

This chapter describes some advanced functions that you can perform on your new base station. If you find that certain functions are too complicated or you don’t understand them, your distributor can do what you need for you.

You can do these types of operations on your gateway:

• Administrative tasks at the system level

• Operations at the application level (RTUs pinging, configuring, data checks, and so forth)

Administrative Tasks at the System Level

Because the A840 Telemetry Gateway is based on Linux, many administrative tasks can be performed on it. Linux is a powerful, rich, and exhaustive environment whose description is outside the scope of this manual. You can consult any of the manuals that have appeared lately on the subject. Under normal use you will not have to deal with such tasks, but we have included this information for those rare occasions when something goes wrong or you need to do some minor maintenance such as changing passwords, firmware upgrades, and the like.

18 CHAPTER 3

Advanced Functions

Stopping and Starting the telemetry gateway

The telemetry gateway has a built-in rechargeable battery that is software controlled. If for some reason you need to stop the telemetry gateway (for example, shipping for service or storing for longer time spans), you need to shut it down by switching off the battery internally, then unplugging the power cable. Proceed as follows:

1.

Shut down addVANTAGE and log into the gateway by means of a communication terminal (for example, Hyperterminal in

Windows, Zterm or BlackNight on a Mac, or minicom in Linux).

Use the standard parameters:

• 19200 baud

• 1 stop bit

• No parity

• Hardware protocol

• Send CR after LF.

A login prompt such as the following appears: telemetry gateway A840 (Drau, Linux 2.4.0-rmk2bluemug1-ges5)

(C) 2001 Adcon Telemetry AG

A840 login:

2.

At the A840 login prompt, type root .

3.

At the password prompt, type 840sw .

Note: The default root password is programmed at the factory. For security reasons, it is strongly recommended to change it.

For more details on how to change it, see “Changing Passwords” on page 19.

4.

The > prompt appears. Type halt .

5.

Several messages appear on your terminal. After you see the last message shown below, you can unplug the unit from the power outlet, because the internal battery is now off.

The system is going down NOW !!

Sending SIGTERM to all processes.

Terminated.

Sending SIGKILL to all processes.

The system is halted. Press Reset or turn off power.

System halted.

CHAPTER 3

Administrative Tasks at the System Level

19

To start the unit, plug the mains cable into the power outlet. After the boot procedure finishes (which takes about 20 seconds), the unit is fully operational.

Changing Passwords

For security reasons you might want to change the password of your gateway. The unit comes from the factory with only two users: root and adv . The root user is intended only for administrative tasks, while adv is used by the addVANTAGE software. The password for root is 840sw and for adv it is addvantage . You can change either password, but if you do so, be sure to keep the new passwords in a secure location.

Complete the following steps to change the root password:

1.

Log into the gateway as root , as described in the first step of

“Stopping and Starting the telemetry gateway” on page 18.

2.

At the login prompt, type passwd .

3.

The system prompts you to enter a new password:

Changing password for root.

Enter the new password (minimum of 5, maximum of 8 characters).

Please use a combination of upper and lower case letters and numbers.

Enter new password:

4.

After you enter the new password, the system prompts you to reenter it to be sure that you didn’t mistype it. Reenter the password:

Re-enter new password:

Password changed.

To change the password for the user adv, the steps are the same, except that you start with: passwd adv

If you do change the password for the user adv, you must also change it in addVANTAGE. To do this, edit the agroexp.ini

file.

Find the section [Communication], which has the following entries:

User=adv

Password=addvantage

Do not change the user name, but type whatever new password you assigned to the adv user. The two password strings in the

20 CHAPTER 3

Advanced Functions hardware and softwre must be identical, or addVANTAGE will not be able to download data from the base station.

Note: Only addVANTAGE 3.45 is compatible with the A840 Telemetry Gateway. If your software is not up to date (check the

File–>About menu in addVANTAGE), download the latest update from Adcon’s web server (http://www.adcon.com).

The updater will update only version 3.40, so if you have an older version, you’ll need to contact your Adcon representative.

Losing a Password

If you misplace or forget your gateway password, follow these steps to change it with a new password:

1.

Open a terminal and connect to the gateway, as described in the first step of “Stopping and Starting the telemetry gateway” on page 18.

1.

Reset the A840 device by gently inserting a paper clip in the hole on the backplane near the serial line connector (see

Figure 3). After you feel a click, remove the paper clip.

reset hole

Figure 3. Resetting an A840 Device

2.

Carefully follow the messages on the terminal. When you see the “Waiting 5 sec for key, to enter console” message, press any key.

3.

At the hermit > prompt, type linux init=/bin/sash .

4.

After Linux finishes booting, you will see the > prompt. Type the following, ending each line by pressing Enter:

CHAPTER 3

Administrative Tasks at the System Level

21 stty igncr cd /etc

/etc/rc.sysinit

5.

Now you can change the root password as described in

Step 2 through Step 4 of “Changing Passwords” on page 19.

6.

After you get the “Password changed” message, type exec /bin/init .

The Linux login prompt is displayed. Now you can log in with your new root password.

Software Upgrades

Both components of your base station have their software stored in Flash EEPROMs. This means that you can upgrade the software at any time; even so, you won’t lose any data while the power is switched off.

The A840 Telemetry Gateway has two kinds of software: a bootloader (called hermit ) and the software proper. Both of them can be upgraded. For free upgrades, check Adcon’s web site for the latest files for your gateway.

Upgrading the bootloader

1.

Make sure you have the correct file. It should have an .hmt extension (for example, hermit-010626.hmt).

2.

Log in as root, as explained in the first step of “Stopping and

Starting the telemetry gateway” on page 18.

3.

Type reboot

4.

Several messages will appear (the procedure can take some

20 seconds). Wait until you see the following message:

Please stand by while rebooting the system.

Restarting system.

Waiting 5 sec for key, to enter console

5.

At this point, press any key to enter hermit (the bootloader).

The following message will be displayed:

Hermit V1.2.1 @00:20:54, Jun 29 2001 hermit>

6.

Now type upgrade

22 CHAPTER 3

Advanced Functions

7.

The system waits for a file to be sent using the Y-modem protocol. Configure your terminal program to send via the Ymodem protocol, switch your communication program to

Send, and send the .hmt file from your computer.

8.

After a series of messages, the system asks for confirmation.

Press Y. The bootloader will now be replaced.

9.

Restart the gateway by typing linux

After Linux finishes booting, the gateway is again ready for use.

To upgrade the system

1.

Make sure that you have a new system image (the image file name usually ends with .img).

2.

Log in as root, as explained in the first step of “Stopping and

Starting the telemetry gateway” on page 18.

3.

Type reboot

4.

Several messages will appear (the procedure can take some

20 seconds). Wait until you see the following message:

Please stand by while rebooting the system.

Restarting system.

Waiting 5 sec for key, to enter console

5.

At this point, press any key to enter hermit (the bootloader).

The following message will be displayed:

Hermit V1.2.1 @00:20:54, Jun 29 2001 hermit>

6.

Change the serial port speed by typing set speed 115200

7.

Change the speed of the communications program to 115200 baud, then press Enter. You’ll see the hermit> prompt again.

8.

Type upgrade

9.

The system waits for a file to be sent using the Y-modem protocol. Configure your terminal program to send via the Ymodem protocol, switch your communication program to

Send, and send the .img file from your computer. The download can take several minutes.

CHAPTER 3

Operations at the Application Level

23

10. After a series of messages, the system asks for confirmation.

Press Y. The system software will now be replaced. The procedure can take several minutes.

Note: Do not switch the system off during this time!

11. When the procedure is finished and you see the hermit> prompt again, restart the gateway by typing linux

12. While the system is booting, return your terminal’s speed to

19200.

After Linux finishes booting, the gateway is again ready for use.

Operations at the Application Level

The gateway currently has only one factory-installed application, the emu3ap application (an emulator of the A730SD receiver).

Using this application puts you in an environment almost identical to the A730SD receiver.

You can access the emu3ap application in either of these ways:

• Log in as user adv and you are automatically dropped to an emu3ap shell.

• Log in as root and, at the Linux prompt, type emu3ap

In either case, you need to press Enter until you get a message stating that you are in the emu3ap command line interpreter (CLI).

Note: You can reach the gateway over the serial port or over the built-in modem. If the network is enabled (this operation is not described in this manual), you can also reach it over ethernet. You can have several emu3ap processes running at the same time.

Although the emu3ap software and the A730SD are very similar, there are some slight differences in that some commands were eliminated and other features were added.

Commands Accepted by the emu3ap Emulator

As with the A730SD, the emu3ap software supports four different classes of commands:

24 CHAPTER 3

Advanced Functions

• Configuration (including the SET commands)

• Data

• Administrative

• Direct radio

Configuration Commands

This category includes commands that configure various parameters of the emu3ap software.

D

ESCRIPTION

P

ARAMETERS

R

ETURNS

R

EMARKS

E

XAMPLE

D

ESCRIPTION

P

ARAMETERS

R

ETURNS

R

EMARKS

E

XAMPLE

D

ESCRIPTION

INSERT

Inserts a new device in the gateway’s internal list.

The device ID number.

OK or an error message.

A device is a remote measuring station (for example, A730MD,

A720, A723, or A733). Once the device has been inserted, various operations can be performed on it. Every 15 minutes, the gateway automatically asks the devices in the list to supply a new slot of data over radio. The 15 minutes interval can be changed with the

SET SLOT command (see page 28).

insert 2333

OK

REPLACE

Replaces one device with another. Data from the original device is not lost, but is associated with the new one.

The original device ID and the new device ID.

OK or an error message.

The REPLACE command effectively replaces one device with another. Use it when replacing a station in the field. In the following example, device 2333 is replaced by device 2046.

replace 2333 2046

OK

DELETE

Deletes a device.

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

CHAPTER 3

Operations at the Application Level

25

The device ID.

OK or an error message.

None.

delete 2046

OK

ROUTE

Sets a route for the target device.

The device ID and the route description (composed of the routing devices’ IDs). To clear a route, provide only the target device ID (in other words, a null route).

OK or an error message.

The ROUTE command updates the internal descriptors for the specified target device. Normally, after inserting a new device, it is assumed that this device is to be called directly, that is, no routing stations are in between. If a station has to be routed over one or more other stations, the gateway must know the path to be used when calling that station. The route is given as a list of devices, always starting from the gateway and progressing to the endstation (see example below). Note that the number of relay stations is limited to 8, which is in practice more than sufficient. To verify the route a specific device uses to communicate, use the

INSPECT command (see page 31).

route 2333 2400 2402 2500

OK

In the example above, station 2333 is routed over a path defined by devices 2400, 2402 and 2500. This corresponds to the following topographic situation:

2333 base station

2402

2500

2400

To clear a route, use the same command, but include no parameters for the path:

26 CHAPTER 3

Advanced Functions

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E

XAMPLES route 2333

OK

MASTER

Set/resets the master flag of a specific device.

The device ID and the flag value (on/off).

OK or an error message.

When a station has a master flag set, the gateway uses that station for date/time synchronization. It is important to understand that each remote station has an internal real-time clock, used to stamp the stored data. This clock has to be initialized and synchronized, which the gateway does automatically when either of the following occurs:

• A station returns invalid time values (null or out of date).

• The host computer synchronizes the time of the gateway (such as with a SET TIME command).

If the remote stations in a network are to be polled by more than one base station, only one of those base stations should be used to synchronize the time of a particular RTU. Otherwise, the remote stations could get confused due to the time differences that might occur between different base stations. Consequently, in a multigateway network, only one gateway should have the master flag set for a specific station; all other gateways should treat it as a slave.

To verify whether a device has the master bit set, use the INSPECT command (see page 31).

master 2333 on

OK master 2333 off

OK

EXTEND

This command is deprecated in emu3ap. It has been included for compatibility purposes, but always returns OK.

SET Commands

The SET command has many subcommands, because as its name implies, it sets various parameters of the emu3ap application. Most

E XAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

CHAPTER 3

Operations at the Application Level

27 of the SET commands have a get form, in which only the subcommand is typed and the emu3ap application returns the requested information.

SET TIME

Sets the internal real-time clock of the emu3ap.

The time in the following format: dd/mm/yyyy hh:mm:ss (24-hour clock format).

OK or an error message.

The year may be sent either in two- or four-letter format (for example, 1999 or 99), but the four-letter format is preferred. In addition, the emu3ap also accepts the year 2000 and years thereafter as hundreds, for example, 100 for 2000, 101 for 2001, and so forth.

The date/time parameters may be sent with or without leading zeros. The get variant TIME (with no parameters) returns the current date and time of the device.

set time 4/6/2001 20:1:0

OK time

Local time is: Sun Jun 4 20:01:07 2001

OK

SET FREQ

Sets the operating frequency and step of the gateway (this parameter is further transmitted to the A440 Wireless Modem).

The frequency and step, both in Hz.

OK or an error message.

The get variant FREQ (with no parameters) returns the actual operating frequency.

set freq 433925000 25000

OK freq

Frequency: 433925000, step: 25000

OK

In the example above, the gateway plus wireless modem combination operates on 433.925 MHz with channel spacing of 25 kHz.

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

28 CHAPTER 3

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SET OWNID

This command is deprecated in emu3ap. It has been included for compatibility purposes, but always returns OK.

The radio network ID is programmed at the factory and resides in the A440 Wireless Modem (as for all RTUs, the network ID is the serial number printed on the RTU’s label).

SET SLOT

Sets the request rate in seconds (the default is 900, or 15 minutes).

Note that the poll time is different from device to device, that is, not all devices will be polled at the same time, but instead based on their insertion time.

The request rate in seconds (minimum 10, maximum 10800 seconds, that is, 3 hours).

OK or an error message.

If this parameter is not programmed explicitly, it defaults to 900.

The get variant SLOT (with no parameters) returns the current requesting rate.

set slot 900

OK slot

Slot time is 900 seconds

OK

SET DELAY

Sets the delay before returning ERROR 15 in case of a temporary radio communication breakdown (see also “GETBLOCK” on page 29).

The delay value (minimum 1800, maximum 10800 seconds; in other words, between 30 minutes and 3 hours).

OK or an error message.

If this parameter is not programmed explicitly, it defaults to 3600 seconds (one hour). The get variant DELAY (with no parameters) returns the current delay value.

set delay 7200

OK

CHAPTER 3

Operations at the Application Level

29 delay

Interruption delay is 7200 seconds

OK

SET ECHO/NOECHO

This command is deprecated in emu3ap. It has been included for compatibility purposes, but always returns OK. The behavior of the emu3ap software is that ECHO is always on. You can also PING and REQUEST data even for devices that are not shown in the devices list.

Data Commands

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

This category included commands that return data from the remote stations. The data collected from the stations is stored in the on-board FIFO memory; it can be retrieved based on the station ID and the time stamp. This means that if specific data was retrieved, it can be retrieved again later as long as an appropriate command is given. The data is stored in frames for each station and each time slot (that is, every 15 minutes). The data can be retrieved in any order, each device having its own internal pointers managed by the system. As new data comes in, the old data is overwritten; a “garbage collector” takes care of that. The command that allows this data retrieval is presented below.

GETBLOCK

Returns a block of data found at the current position of the pointer, for the specified device. If a date/time parameter is supplied, GET-

BLOCK searches and positions the internal pointer on that date/ time before returning the data block.

The device ID and, optionally, the date/time parameter.

A string of data depending on the device type, or an error message. Some important error messages are 14 (no more data) and

15 (radio communication temporary breakdown). The latter means that data might come later if the communication is reestablished.

The number of concatenated frames in a block depends on the frame length (the maximum is 1024 bytes in a block). The bytes are sent without spaces, but with leading zeros if necessary.

getblock 2006 25/5/2000 15:15:0

1905640F11361509DFC9F8000057AB7F0F1A006702AB7F0F0100

6F021905640F20361509D7C4F8000056A9830F19005B02A9830F

010060021905640F2F361509C9B2F8000056AA800F1A006B02AA

30 CHAPTER 3

Advanced Functions

8110010075021905641002361509DECAF8000056AA800F18004F

02AA800F010055021905641011361509D8C1F8000056AA7D0F16

004D02AA7E0F010055021905641020361509D2BBF8000056A87F

0F13004002A8800F01004602190564102F361509DBB2F8000056

A97E0F19005102A97F0F010059021905641102361509CAB9F800

0056A97C0F1E004501A97C0F01004E021905641111361509C6B1

F8000055A6840F1A001F01A6840F010020011905641120361509

D7C3F8000055A4870F11001101A4870F01001101190564112F36

1509D1C1F8000055A4870F13001601A4870F0000170119056412

02361509DAC3F8000055A5860F12001A01A5860F01001C011905

641211361509DBC8F8000055A6830F13002C01A6840F01003201

1905641220361509D7C5F8000055A5841014001E01A5840F0100

2001190564122F361509DBC0F8000055A4840F14001701A4850F

010016011905641302361509DFCFF8000055A3860F13001501A3

8610000015010F

OK

To help you understand how the block must be interpreted, the first two frames and the last frame in the block are displayed below

(notice the extra carriage returns inserted to help you see the individual frames):

1905640F11361509DFC9F8000057AB7F0F1A006702AB7F0F0100

6F02

1905640F20361509D7C4F8000056A9830F19005B02A9830F0100

6002

...

1905641302361509DFCFF8000055A3860F13001501A386100000

1501

0F

The last byte on the last line is the checksum of the whole block

(modulo 255). It is the sum of all the bytes, ignoring the overflows.

Note: The dates for years greater than 1999 are returned in a three-digit format, that is, 100 for 2000, 101 for 2001, and so on.

The data portion of the frame is frame-type dependent, which in turn depends on the RTU that generated it (see “Frame Types” on page 39 for a description of all frame types currently in use). However, separating individual frames from a GETBLOCK string is easy if you consider the following:

• Each frame has a header and a data portion.

• Whatever the data portion is, the header has a constant structure and known length (date/time and number of bytes in the data segment).

Thus, to identify the beginning of the next frame you need only parse the date/time and the frame size and then jump to the next frame based on the size of the data portion (adding the frame size to the current position points in effect to the beginning of the next frame).

CHAPTER 3

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31

Administrative Commands

This category describes the commands that return certain status information.

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

DESCRIPTION

PARAMETERS

RETURNS

REMARKS

EXAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

VER

Returns the current version of the emu3ap software.

None.

OK or an error message.

None.

ver

Adcon Telemetry emu3ap, version 3.02

OK

TYPE

Returns the hardware platform of the emu3ap.

None.

OK or an error message.

None.

type

A7840

OK

INSPECT

Returns a list of devices and associated information such as the ID of the device, and the date and time of the last stored slot. You can also use this command with a parameter. For example, INSPECT device ID causes the emu3ap software to return specific information concerning the requested device.

None or a device ID (two variants).

The list of devices or detailed information regarding a specific device (second variant).

None.

32 CHAPTER 3

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D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

UPTIME

Returns the amount of time the A440 Wireless Modem connected to the gateway has been operational.

None.

The amount of time the wireless modem has been in operation.

None.

uptime

Up 230 day(s), 10 hour(s), 14 minute(s)

OK

NOP

This command is deprecated in emu3ap. It has been included for compatibility purposes, but always returns OK. The A840 Telemetry Gateway’s software is stored in its internal Flash EEPROM.

HELP

Returns all the available commands in the emu3ap software.

None.

A list of commands.

QUIT

Exits the emu3ap software. If you were logged in as the user adv , you will be returned to the Linux login prompt. Otherwise, you will be returned to a Linux shell.

None.

Nothing.

You can use the EXIT command with the same result.

Direct Radio Commands

This category describes several commands that allow the host to communicate directly with the remote stations or other base stations. These commands take a longer time to complete. The exact amount of time depends on how the end-station is routed and how much time it takes the frames to travel from one station to another.

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLES

CHAPTER 3

Operations at the Application Level

33

The direct radio commands return by default results such as OK or a specific error number. Complete details about the direct radio commands can be found in the user manuals for the respective devices (A730MD, A720, A723, and A733).

PING

Returns information about the specified device such as the RF levels, the date and time of the internal real-time clock of the station, the software version in the station, and the number of reserved bytes.

The RTU’s ID.

A string or an error message (for example, ERROR 35 means timeout). The strings and parameters returned depend on the remote device type. Following is an explanation of the information returned:

• Incoming RF is the level recorded by the receiving station.

• Outgoing RF is the level at which the sending station received the requesting station.

• Pout represents the output power of the transmitter while it is sending the answer to the ping frame.

• The date/time represents the actual value of the local realtime clock.

• Ver is the software version of the RTU.

• Clk, stk, and cop contain Adcon-specific information.

• The uptime represents the time the device has operated since the last reset or internal watchdog reset.

• The battery and internal temperature are self-explanatory.

• RSSI (relative signal strength), PMP (power management parameters), and Slot are the current settings of the device.

None.

ping 2006

Type A730MD

Dev 2006: incoming RF 247, outgoing RF 225

Time Fri Jun 2 16:24:04 2000

Ver C5, clk 00, stk FF, cop FF

Reserved bytes 00 00 00 00 00 00 00 00 00 00

OK ping 6383

Type A720

Dev 6383: incoming RF 255, outgoing RF 255

34 CHAPTER 3

Advanced Functions

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

Time Fri Jun 2 16:24:15 2000

Ver 22, clk 00, stk 00, cop 00

Uptime 396 day(s), 22 hour(s), 33 minute(s)

Batt 6.9 volts, internal temp 31 Celsius

Settings: RSSI 58, PMP 65 72, Slot 900 3

OK ping 9471

Type A733

Dev 9471: incoming RF 255, outgoing RF 166, Pout: 182

Time Fri Jun 2 16:27:12 2000

Ver 0F, clk 00, stk 00, cop 05

Uptime 143 day(s), 7 hour(s), 44 minute(s)

Batt 7.0 volts, internal temp 27 Celsius

Settings: RSSI 85, PMP 65 72, Slot 900 15

OK

REQUEST

Returns a slot of data from the remote’s FIFO memory.

The RTU’s ID and, optionally, the date/time and/or the init string.

A string with data or an error message. The strings returned depend on the remote device type (see the examples below). The most common error messages are ERROR 35 (timeout) or ERROR

36 (RF channel in use).

None.

request 2006

Dev 2006: incoming RF 255, outgoing RF 252

Time Thu Nov 2 21:42:21 1995

Data FF 00 00 51 72 DF 10 16 AC 04 01 71 DF 12 16 AC

04 01

OK

The command has several variations. If given as in the example above, the most recent slot stored in the station’s FIFO is returned.

By specifying a date and a time as parameter, the station returns the first slot “younger” than the specified date and time: request 2006 2/11/95 20:0:0

Dev 2006: incoming RF 255, outgoing RF 251

Time Thu Nov 2 20:12:21 1995

Data FF 00 00 51 72 E1 12 0C AF 04 01 72 E1 10 0C AF

04 01

OK

Furthermore, if the INIT parameter is also specified after the date and time, the station’s real-time clock will be resynchronized with that of the gateway’s internal date and time: request 2006 2/11/95 20:0:0 INIT

Dev 2006: incoming RF 255, outgoing RF 251

Time Thu Nov 2 20:12:21 1995

Data FF 00 00 51 72 E1 12 0C AF 04 01 72 E1 10 0C AF

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

CHAPTER 3

Operations at the Application Level

35

04 01

OK

Note: This is a forced time initialization of an RTU. In practice it is not needed, because the gateway does it automatically when it is itself initialized by means of the time command

(see “SET TIME” on page 27).

An A720 device responds as follows: request 6383

Dev 6383: incoming RF 255, outgoing RF 255

Time Fri Jun 2 17:01:35 2000

Data 4E 00 00 58 A5 60 01 00 00 86 00

OK

An A733 device responds as follows: request 9471

Dev 9471: incoming RF 255, outgoing RF 122

Time Fri Jun 2 17:04:42 2000

Data 7F 00 00 00 00 00 00 00 00 59 00 16 AF 6B 20 01

00 00 00 A8 55 AF 13 A0 00 00 00 00

OK

Note: The internal FIFO of the A730MD RTUs is limited to 11 slots, which means about 2-3/4 hours of stored data. The A720 series 2 can store up to 240 slots (about 2.5 days), while the

A733 RTUs can store up to 1024 slots (a little over 10 days).

Older data will be overwritten.

RSETIO

Acts upon the I/O ports of a remote device. It can switch a port to input or output mode and can also switch a port configured as output to a logical one or zero state.

The RTU’s ID, the value of the data direction register (DDR), and the value of the port itself (DATA). All values are in hex. The DDR and DATA bits must be OR-ed according to the required state of the ports.

The actual state of the port (in hex).

This command is deprecated; it is supported only by the A730MD devices and early A720 devices (series 1). New devices use the more advanced PORT command.

rsetio 2003 0 0

DDR 02, REG 5F

OK

36 CHAPTER 3

Advanced Functions

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

PORT

Acts upon the I/O ports of a remote device.

The RTU’s ID, the byte code, and parameters (for some forms of the command). All parameters are in decimal form (pay particular attention to the byte code because it must be translated to decimal).

Status result, depends on command.

This command is currently supported only by the A720 (series 2) and A723 (series 3) addITs and A733 addWAVE RTUs.

port 9473 0

Dev 9473: incoming RF 255, outgoing RF 255

Value: 255, Error level: 0

OK

ANALOG

Acts upon the analog input ports of a remote device.

The RTU’s ID, the byte code, and parameters (for some forms of the command). All parameters are in decimal form (pay particular attention to the byte code because it must be translated to decimal).

Status result, depends on command.

This command is currently supported only by the A723 (series 3) addITs and the A733 addWAVE RTUs.

analog 9473 0

Dev 9473: incoming RF 255, outgoing RF 255

Average method: 1 2 3 4 5 6 7 5 5 5 5 5 0 0 0 0

Error level: 0

OK

B

Issues a broadcast request frame that forces all listening devices to answer.

None.

A list of devices that answered.

None.

b

From 2003: incoming RF 255, outgoing RF 255

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

CHAPTER 3

Operations at the Application Level

37

From 2646: incoming RF 188, outgoing RF 141

From 9474: incoming RF 255, outgoing RF 255

From 2419: incoming RF 255, outgoing RF 254

From 2464: incoming RF 255, outgoing RF 255

From 10843: incoming RF 255, outgoing RF 255

OK

RB

Forces the specified remote device to issue a broadcast request frame that forces all listening devices to answer. By subsequently using the RBLIST command, a list of all the stations heard from can be retrieved.

The ID of the remote.

OK or error.

Currently only the A723 addIT and the A733 addWAVE devices support this command. At least 12 seconds must elapse between the time you issue the RB and RBLIST commands.

rb 9473

Error level: 0

OK

RBLIST

Returns a list of all the stations heard from after a broadcast request.

The ID of the remote.

A list of the stations heard from.

Currently only the A723 addIT and the A733 addWAVE devices support this command. At least 12 seconds must elapse between the time you issue the RB and RBLIST commands.

rblist 9473

Dev 9473: incoming RF 255, outgoing RF 255

Last Broadcast: Mon Jun 19 12:50:31 2000

201: 255

4446: 255

2622: 255

6127: 255

10820: 255

11127: 255

2646: 255

2008: 255

OK

38 CHAPTER 3

Advanced Functions

D ESCRIPTION

P ARAMETERS

R ETURNS

R EMARKS

E XAMPLE

Error Messages

RSET

Issues remote SET commands, which set parameters in the RTUs.

Not all the RTUs support these commands, most notably the

A730MD devices don’t support it.

The ID of the remote, the set-command, and its parameters.

OK or an error message.

Currently only the A720 (series 2), A723 (series 3) addIT, and the

A733 addWAVE devices support this command. The following remote set commands are supported: ID, SLOT, PMP, FREQ, FDEV, and SST. Not all devices support all commands.

rset 11123 slot 600 10

OK

The emu3ap software might return any of several error messages.

Some are self-recoverable after a retry and others are simply warnings. These messages are returned instead of the OK prompt.

• 1 — Nonexistent command

• 2 — CLI buffer overflow

• 3 — Internal error

• 5 — Invalid or missing parameter

• 10 — Device not found

• 11 — Device already exists

• 13 — No more space for device descriptors

• 14 — No more records for the requested device

• 15 — Remote device currently unavailable (radio connection temporarily interrupted)

• 18 — Reserved device numbers (that is, 0)

• 20 — Incorrect time supplied, conversion not possible

• 30 — Error receiving a frame (cyclic redundancy check and others)

• 31 — An unexpected frame type was received

• 32 — False length (type does not fit its length)

• 35 — Radio timeout when receiving (no answer after a request

• 36 — RF channel in use

CHAPTER 3

Operations at the Application Level

39

Frame Types

S IZE

F ORMAT

The information in this section is intended to programmers writing their own routines to interface with the A840 Telemetry Gateway.

The A840/A440 combination can communicate with various types of RTUs. The distinctive frame type of each RTU makes no difference to the application software on the A840. The software stores the frame in the memory and retrieves it when needed—whatever its length is. But it is important for the software on the host to correctly interpret the frames returned by the gateway.

The data is retrieved from the gateway using the GETBLOCK command (see page 29). All frames have certain common elements: the date/time, the number of following bytes (including the frame type), the frame type, and the data portion. Clearly, the only difference between the various frames is the data portion (the size and type are also different from frame to frame). Following are descriptions of the frames that are currently in use.

date (6 bytes) time (6 bytes) size (1 byte) frame type (1 byte) data ( size bytes)

The A730MD frames

The A730MD uses frame type 9.

Type 9

21 (including the type byte).

struct tlg_type9 {

BYTE RF_LevelIn;

BYTE

BYTE

RF_LevelOut;

DigiByte;

BYTE

BYTE

BYTE

BYTE

PulseCounter0;

PulseCounter1;

BatteryLevel;

Analog1;

BYTE

BYTE

BYTE

BYTE

Analog2;

Analog3;

Analog4;

Analog5;

40 CHAPTER 3

Advanced Functions

};

BYTE

BYTE

BYTE

BYTE

BYTE

BYTE

BYTE

BYTE

BYTE

Analog6;

Analog7;

Analog8;

Analog9;

Analog10;

Analog11;

Analog12;

Analog13;

Analog14;

CHAPTER 3

Operations at the Application Level

41

D ESCRIPTION

Analog11

Analog12

Analog13

All values are 8 bits and must be converted accordingly, depending on the sensor connected. Figure 4 shows the placement of various inputs on the connectors.

Analog4

Analog5

Analog6

Y-box #1

From WIND (A730MD)

EXTENDED EXTENDED DEFAULT DEFAULT

Analog8

Analog9

Analog10

Analog1

Analog2

Analog3

Y-box #2

COMMON

From SENSOR (A730MD)

EXTENDED EXTENDED DEFAULT DEFAULT

Analog14 Analog7

Y-box #3

COMMON

From RAIN (A730MD)

EXTENDED EXTENDED DEFAULT DEFAULT COMMON

Figure 4. A730 Connector Inputs

Note: If no Y-boxes are installed, the values sampled on channels 1 to 7 will be duplicated on channels 8 to 14. The drawing above does not imply that all the Y-boxes must be in place.

In fact, adding the third Y-box makes little sense because only one analog input can be duplicated on the RAIN connector.

42 CHAPTER 3

Advanced Functions

S

IZE

F

ORMAT

The RF level is nonlinear and results from a table (which you can get from Adcon as an ASCII file). The value of the battery can be computed as follows:

Batt =

BatteryLevel • 20

----------------------------------------------

255

The digibyte is essentially the reflection of several inputs or internal status bits on the A730MD; its structure is described below:

B7 B6

S.C. AUX:4

B5 B4 B3 B2 B1 B0

N.U.

RAI:3 RAI:4 AUX:2 AUX:3 AUX:5

S.C. = Solar Cell status N.U. = Not used RAI = Rain AUX = Aux

For more details, refer to the user manual for the A730MD device

(addVANTAGE A730).

The A720 (addIT) Frames

The addIT uses a reduced frame type (38). No adapter use for extending the inputs is possible.

Type 38

14 (including the type byte).

struct tlg_type38 {

BYTE RF_LevelIn;

BYTE

BYTE

RF_LevelOut;

DigiByte;

BYTE

BYTE

BYTE

BYTE

PulseCounter0;

PulseCounter1;

BatteryLevel;

Analog1;

BYTE

BYTE

BYTE

BYTE

BYTE

BYTE

Analog2;

Analog3;

Analog4;

Analog5;

Analog6;

Reserved;

};

D ESCRIPTION

CHAPTER 3

Operations at the Application Level

43

All values are 8 bits and must be converted accordingly, depending on the sensor connected. Figure 5 shows the placement of various inputs on the connectors.

Power

DIG1

Analog4

Analog5

7

6

5

4

1

2

3

PulseCounter1

Ground

I/O A

Analog6

A720 Power

DIG0

Analog1

Analog2

7

6

5

4

1

2

3

PulseCounter0

Ground

I/O B

Analog3

Figure 5. A720 Connector Inputs

The RF level is nonlinear and results from a table (which you can get from Adcon as an ASCII file). The value of the battery can be computed as follows:

Batt =

BatteryLevel • 20

----------------------------------------------

255

The digibyte is essentially the reflection of several inputs or internal status bits on the A720; its structure is described below:

B7

S.C.

B6 res

B5 res

S.C. = Solar Cell status

B4 res res = reserved

B3 res

B2 res

B1 B0

DIG1 DIG0

For more details, refer to the user manual for the A720 device.

The A723 (addIT series 3) Frames

The addIT series 3 implements currently two frame types, depending on the compatibility mode flag: 38 (described on page 42) and

39. For more details about the compatibility flag, refer to the A720 series user manual.

There is, however, a fundamental difference between frame 39 and the previously described data frames. The A723 samples the analog values with 10-bit resolution and stores them as 12-bit values.

44 CHAPTER 3

Advanced Functions

S IZE

F ORMAT

D ESCRIPTION

0

Analog1

Also, the A723 contains two 16-bit pulse counters, that is, it has more data to send. Due to the limited space available and to minimize the radio traffic, the frames are slightly compressed, in that six

12-bit values are packed in 9 bytes.

Type 39

22 (including the type byte).

struct tlg_type37 {

BYTE RF_LevelIn;

BYTE

BYTE

RF_LevelOut;

DigiByte;

WORD

WORD

BYTE

BYTE

PulseCounter0;

PulseCounter1;

BatteryLevel;

Analog[9];

};

The analog values are 12 bits and must be converted accordingly, depending on the sensor connected, while the pulse counters are

16-bit values. Only the RF and battery levels are 8-bit values.

Analog[9] is an array of 9 unsigned bytes that is the result of packing the six 12-bit values. These are the values returned by the internal A/D converter from the respective I/O connectors.

Note: The integers (16-bit values) are sent using the big endian convention, that is, first the most significant byte and then the least significant byte.

The packing mechanism is shown in Figure 6.

0

Analog2

Six 16-bit values

Analog3

0 0

Analog4 etc....

12 bits 12 bits 12 bits 12 bits

Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5

8-bit packed values

Byte 6 Byte 7 Byte 8

Figure 6. Type 39 Frame Compression

CHAPTER 3

Operations at the Application Level

45

Note: Only Analog1 to Analog6 are packed; the 16-bit Pulse

Counters are not.

Figure 7 shows the placement of various inputs on the connectors.

Power

DIG0

Analog1

Analog2

7

6

5

4

1

2

3

PulseCounter0

Ground

I/O A

Analog3

A723 Power

DIG1

Analog4

Analog5

7

6

5

4

1

2

3

PulseCounter1

Ground

I/O B

Analog6

Figure 7. A723 Connector Inputs

The RF level is nonlinear and results from a table (which you can get from Adcon as an ASCII file). The value of the battery can be computed as follows:

Batt =

BatteryLevel • 20

----------------------------------------------

255

The digibyte is essentially the reflection of several inputs or internal status bits on the A723; its structure is described below: b7

S.C.

res res res res res b0

DIG1 DIG0

S.C. = Solar Cell status res = reserved

For more details, refer to the user manual for the A723 device.

The A733 (addWAVE) Frames

The addWAVE currently implements only one frame type (37). The

A733 samples the analog values with 10-bit resolution and stores them as 12-bit values. Also, the A733 contains built-in logic to sample 12 different analog inputs, as well as four 16-bit pulse counters—all in all, substantially more data. Due to the limited space available and in order to minimize the radio traffic, the frames are slightly compressed, in that twelve 12-bit values are packed in nine 16-bit words.

46 CHAPTER 3

Advanced Functions

S IZE

F ORMAT

D ESCRIPTION

0

Analog1

Type 37

31 (including the type byte).

struct tlg_type37 {

BYTE RF_LevelIn;

BYTE

BYTE

RF_LevelOut;

DigiByte;

WORD

WORD

WORD

WORD

BYTE

BYTE

PulseCounter0;

PulseCounter1;

PulseCounter2;

PulseCounter3;

BatteryLevel;

Analog[18];

};

The analog values are 12 bits and must be converted accordingly, depending on the sensor connected, while the pulse counters are

16-bit values. Only the RF and battery levels are 8-bit values.

Analog[18] is an array of 18 unsigned bytes that is the result of packing the twelve 12-bit values. These are the values returned by the internal A/D converter from the respective I/O connectors.

Note: The integers (16-bit values) are sent using the big endian convention, that is, first the most significant byte and then the least significant byte.

The packing mechanism is shown in Figure 8.

0

Analog2

Twelve 16-bit values

Analog3

0 0

Analog4 etc....

12 bits 12 bits 12 bits 12 bits

Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5

8-bit packed values

Byte 6 Byte 16 Byte 17

Figure 8. Type 37 Frame Compression

Note: Only Analog1 to Analog12 are packed; the 16-bit Pulse

Counters are not.

CHAPTER 3

Operations at the Application Level

47

Figure 9 show the placement of various inputs on the connectors.

Power

DIG0

Analog1

Analog2

7

6

5

4

1

2

3

PulseCounter0

Ground

I/O A

Power

DIG2

6

7

5

4

1

2

3

Analog3

Analog7

Analog8

PulseCounter2

Ground

I/O C

Analog9

A733 Power

DIG1

Analog4

Analog5

7

6

5

4

1

2

3

PulseCounter1

Ground

I/O B

Analog6

Power

DIG3

7

6

5

4

1

2

3

Analog10

Analog11

PulseCounter3

Ground

I/O D

Analog12

Figure 9. A733 Connector Inputs

The RF level is nonlinear and results from a table (which you can get from Adcon as an ASCII file). The value of the battery can be computed as follows:

Batt =

BatteryLevel

255

•

20

The digibyte is essentially the reflection of several inputs or internal status bits on the A733; its structure is described below: b7

S.C.

res res res b0

DIG3 DIG2 DIG1 DIG0

S.C. = Solar Cell status res = reserved

For more details, refer to the user manual for the A733 device.

48 CHAPTER 3

Advanced Functions

Frame Parsing Example

To better understand how the retrieved frames must be processed, this section provides an example of such processing. Let’s suppose that we used the GETBLOCK command and retrieved a block of frames of type 37. After parsing the block, we separate it into individual frames as described in “GETBLOCK” on page 29. Because all the frames are treated identically, we will show you how to interpret only one of them from the block. The frame looks something like this:

02066411312A1F25FF7B7F0000000000000000590016AC6B0000

000000A6D5E81C40000000000206

Separating the date/time, frame type and size, and the data segment, we get this:

020664: Date (2/6/00)

11312A: Time (17:49:42)

1F: Size (31 bytes)

25: Frame type (37)

FF7B7F0000000000000000590016AC6B0000000000A6D5E81C40

00000000: Data

Using the description of frame 37, we can parse the data segment.

To show this more easily, we will rewrite the frame with spaces inserted between different elements:

FF 7B 7F 0000 0000 0000 0000 59 001 6AC 6B0 000 000

000 A6D 5E8 1C4 000 000 000

Now we can easily map the elements onto the frame 37 structure:

FF: RF in

7B: RF out

7F: Digibyte

0000: PulseCounter0

0000: PulseCounter1

0000: PulseCounter2

0000: PulseCounter3

59: BatteryLevel

001: Analog1

6AC: Analog2

6B0: Analog3

000: Analog4

000: Analog5

000: Analog6

A6D: Analog7

5E8: Analog8

1C4: Analog9

000: Analog10

000: Analog11

000: Analog12

The last step is to convert the analog values to actual engineering units. This is easily accomplished if we know what sensor is connected to each input of the RTU, and its conversion equation. Let’s

CHAPTER 3

Operations at the Application Level

49 assume that a temperature sensor is connected to the Analog7 input. Then:

Temp

[ °

C

]

=

2669 100

40

4095

– = 25.17

Note that 2669 is A6D converted to decimal while the -40 was necessary because the standard Adcon temperature sensor has a range from -40 to 60 ºC.

Similarly, the battery level can be computed as follows:

Batt =

89 20

6.98

255

=

Note here that we had to deal with an 8-bit value (59 hex = 89 decimal), so the divider is 255, while the previous example was based on a 12-bit conversion and the divider was 4095.

50 CHAPTER 3

Advanced Functions