Omron C200HW-PRM21 Operation Manuals page 78

Control and status area
62
IR n.01 I/O communication inhibit
0: I/O communication is enabled.
1: I/O communication is disabled. A transition from 0 to 1
changes the PROFIBUS-DP network state from 'Operate' via
'Clear' to 'Stop'. All remote outputs will therefore be reset.
Data in the input buffer of the Unit will no longer be updated
and transferred to the PLC anymore (I/O refresh time will
decrease). The PLC's output data however, is still transferred
to the output buffer of the Unit. This ensures that the output
buffer contains valid output data at the moment the communi-
cation is enabled again.
When I/O communication is disabled, the output mailbox is
disabled as well. It is possible to send mailbox commands to
the Unit, but they are not transferred to the output mailbox.
Because no commands are put in the output mailbox, no
responses will be received in the input mailbox.
IR n.02 Input mailbox clear
0: No specific action.
1: Each I/O refresh, one unprocessed response (if available) is
removed from the input mailbox.
IR n.03~06 Not used by C200HW-PRM21.
IR n.07 Issue control command
0: No control commands are issued.
1: Each I/O refresh, one control command is issued.
The control command is specified by IR n.09~13, and the
destination is specified by IR n+1. No control command is
transferred to the output mailbox if either the RUN-bit (IR
n.00) is not set or if the communication is inhibited (IR n.01) or
the output mailbox is not ready to receive a command due to a
full input mailbox. In the next PLC cycle, IR n+2.11 will
indicate whether the control command was accepted or not.
Each fieldbus cycle, only one control command will be
transmitted.
IR n.08 Not used by C200HW-PRM21.
IR n.09~13 Specification of the PROFIBUS-DP control command.
Bit Command
09 Clear_Data
10 Unfreeze
11 Freeze
12 Unsync
13 Sync
When activated simultaneously, Unsync has priority over Sync,
Meaning
Clear output data
Unfreeze input data
Freeze input data
Unsynchronise output data
Synchronise output data
Section 5-3