CALL PLCWRITE Statement
Purpose:
This command is used to write value(s) to a PLC’s register(s), memory
location(s), or to force one or more output bits in a PLC. Refer to the -PL5
and -SL5 for information on how to use this command with the
Allen-Bradley PLC-5 and SLC-500 processors.
Syntax:
CALL PLCWRITE(id,cmd,start address,# of
registers/bits,expression/variable/array )
Comments:
id specifies the address of the PLC to which you wish to write. This number
is usually 1 when interfacing to one PLC.
cmd specifies the write operation you wish to perform. See the table below
for the write operation possibilities:
start address is the starting address of the bit(s) or register(s) you are
interested in writing. In the case of the Modbus, this does not include a data
type specifier (%, $, !, etc.)
MOD GE9 TI3 TI5 OM1 PL2 Cmd Function Typical Data*
•1Clear Status Any 5 words
••• •2Write Input Bit(s) 16 bit words
•• • • • • 3Write Output Bit(s) 16 bit words
•• • • • • 4Write to a Register 1 word per register
5N/A N/A
6N/A N/A
7N/A N/A
• • • 8Write to Analog Output(s) 1 word per output
• • • • • 9Write to Discrete
Internals/Coils/Relays 16 bit words
•10 Write to Holding Relays (bits) 16 bit words
•11 Write to Auxilary Relays (bits) 16 bit words
Table 6
Write Operation Options
PLC Interface Commands CALL PLCWRITE Statement
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