Extron Electronics IN6902 - Manual (Page 6)

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IN6901 / IN6902 OPERATION MANUAL - REV. 2.1 12/01/98 ©1996-1998 - INLINE, INC.
USING RS-232 CONTROL
The IN6901 / IN6902 include an 9-pin D male remote control port which will accept serial commands
from a control system, computer serial port, or any other device capable of sending out serial ASCII
commands at 1200 baud. These commands may be used to control individual relays, multiple relays or
all relays. Using the appropriate RS-232 codes, the unit relays may be commanded to open, close, toggle
to the opposite state, or pulse (temporarily change to the opposite state for 50 msec and return).
When a relay is selected to close, the contact closure is made between the relay and the common. Thus,
closing Relay 1 on the IN6901 results in a closure between pins 6 and 7.
A complete listing of RS-232 codes is included on page 4.
COMMUNICATION PROTOCOL
1200 baud
No parity check
8 data bits
1 stop bit
COMMAND CODE STRUCTURE
All commands sent to the unit must contain a leading code, the command code, and an ending code.
Each command must be completely executed before the unit will accept a new command. When a
command is completed, the unit provides a response code:
“OK” indicates the command was received and executed.
“ERR” indicates there is a problem with the code and the command was not executed.
The IN6901 and IN6902 always look for serial commands with the following delimiters: [ ] Commands
sent without these delimiters will be ignored.
A complete command consists of:
[ The leading code
RLY01C The command code. (This would cause relay 01 to close)
] The ending code
Sample command codes:
[RLY02O] Open Relay 2
[RLY12T] Toggle Relay 12
[LCCCOOO] Load and execute the following states: Relays 01, 02, 03 Closed
Relays 04, 05, 06 Open