Rockwell Automation 1336T PLC Comm. Adapter, Series B, FRN 2.xx-3.xx User Manual

Page 77

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5–3

Publication 1336 FORCE–5.13 –– September, 1998

The two available channels are accessed through parameters 367
(ChA Logic Cmd In) and 368 (ChB Logic Cmd In). Both
parameters have the same bit definitions as the Logic Command.
Therefore, even if you do not set up a channel for RIO
communications, you can still write to parameters 367 and 368 by
using block transfer or by possibly linking to a function block.

Important: In the PLC controller, internal bit numbering is 0

through 15 decimal and I/O bit numbering is 0 through
17 octal. However, bit numbering in the drive
parameters, including ChA Logic Cmd In and ChB
Logic Cmd In, is 0 through 15 decimal. You should
keep this in mind when working with the Logic
Command.

For example, if you want to set the Ramp Disable bit in the Logic
Command (bit 9 decimal), you would need to set bit 11 (octal) in
your PLC program.

If you select the external speed reference, the PLC controller must
send a 16–bit word to parameter 101, Velocity Reference 1 HI, in the
drive. Because the speed reference is a complete 16–bit word, the
PLC controller must send the data as a complete word rather than as
individual bits as was the case for logic command bits.

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