Technical Reference
Electrical Connections
Ethernet
This eBOX port is just like an Ethernet port on a computer, to connect it to a hub, switch or router, use a straight through cab le.
To connect it to another eBOX or computer, use a crossover cable.
The eBOX supports IEEE 802.3u clause 28 Auto-Negotiation which automatically senses the Ethernet port speed & duplex operation and chooses the highest performance settings.
In addition, four LEDs on the front panel that indicate various operating conditions of the Ethernet port. These LEDs are:
• Link
• 100BaseT activity
• 10BaseT activity
• Collision
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Serial
The four serial ports along the to p of the rear panel are 9 pin D-Sub connectors which can be configu red for RS-232C or RS-422A operation. I to appear as n RS-422 mode, the eBOX direction can be configured
a Controller or a Device. In RS-232 mode, the eBOX appears as a DCE or DTE.
RS-232C 2A
Direction To Device To Computer To Deck To Controller
Left SW Out In Out In
Right SW
Pin 1
Pin 2 not used not used not used
Receive Transmit Receive A not used
Transmit A
Pin 3
Pin 4
Pin 5
Pin 6
Pin 7
Pin 8
Pin 9
Transmit not used Ground
Ground Ground Ground not used not used not used not used
Receive not used not used not used not used not used
Transmit B
Ground
Receive B
Transmit A not used
Receive B
Ground
Ground
Ground
Transmit B
Receive A not used
Serial Port Configuration
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Older versions of the eBOX used DIP switches to configure the mode of the ports. In RS-232 mode, the RS-422 ICs must be removed. These ICs are marked 89C22.
Direction To Computer To Deck To Controller
SW1 f
SW2
Pin 1
Pin 2
Pin 3
Pin 4
Pin 5
X On Off not used
Transmit
Receive not used not used not used
Receive A
Transmit B
Ground
Ground Ground
Ground not used
Ground
Ground
G round
Transmit A
Receive B
Pin 6
Pin 7
Pin 8
Pin 9
X = Don’t Care not used not used not used
Receive B
Transmit A not used
Transmit B
R eceive A not used
Serial Port Configuration
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GPI Port Pinouts
The GPI ports on the rear of the eBOX ar e 25 pin D-sub c onnectors. The GPI In connector has 24 TTL/CMOS compatible inputs with internal pull-ups to +5 volts. The GPI Out connector has 24 TT L/CMO S c ut th , pin 1 is the g n -25 are the GP I signals.
When eBOXes connected together in a clie nt/server man ner establish a connection, both client and server eBOXes will send the state of its GPI I n ports to
Out port on the remote
ea ch other s
eBOX. o it c an be sho wn o n the GPI
After that, changes to a GPI In port will cause an eB OX to send a GPI message to the remote eBOX.
Additiona lly, the eBO Xes will s end a GPI me ssa ge every 5 seconds to keep the connection alive and to refresh the state of the
GPI outpu ts.
A packet is sent whenever a change to the GPI In is sensed. At present, it is sampled a bout eve ry 20 millisec onds. This can be changed via the configuration web page.
Byte1
MSB LSB
Pin 9 Pin 8 Pin 7 Pin 6 Pin 5 Pin 4 Pin 3 Pin 2
Byte2
Byte3
P in 17
P in 25
Pin 16 Pin 15 Pin 14 Pin 13 Pin 12 Pin 11 Pin 10
Pin 24 Pin 23 Pin 22 Pin 21 Pin 20 Pin 19 Pin 18 eBOX GPI In/Out Pinouts
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GPI Port Circuitry Details
The eBOX GPI input and output circuits are detailed in th e following section.
The inputs of the eBOX GPI ports are CMOS inputs. The input circuitry has a 4700 ohm pullup resistor to +5 volts as refere nced to pin 1 of the GPI Input Port.
Note: Because the inputs are CMOS, the input voltage MUST be limited to voltage levels between 0 and 5 volts. If this is not possible, consider using the eBOX I/O.
5 Volts
4700 Ω
74HC244
Detail of GPI Input
T k he internal pullup resistor insures that the input pin is set to a nown st ate. T t th I is l a logic stat 1’ G es it T ter ull resist conne or a cte o e m
P t
‘dry con d d o o th example below.
5 Volts
4700 Ω
2 74HC244
1
GPI Input Example with Pushbutton Switch
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The outputs of the eBOX GPI ports are also CMOS. The output signal is referenced to pin 1 of the GPI Output Port. The GPI
Outputs are rated to +/- 6mA. If this is not sufficient for you application, conside r using the eBOX I/O. r
Note: Because the inputs are CMOS, the output voltage MUST be limited to voltage levels between 0 and 5 volts. This can occur if driving a circuit that is powered by a voltage higher than 5 volts. If this is not possible, consider using the eBOX I/O.
74HC 374
Detail of GPI Output
The exampl e circuits below shows a GPI Output driving an LED.
5 Volts
74HC374 2
1
GPI Output Example #1 with LED
74HC374 2
1
GPI Output Example #2 with LED
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