Omron SYSDRIVE 3G3MV User Manual page 233

Communications
·A DSR message can include variables to set data in the I/O memory (such as data
memory) of the CPU Unit or write response data to the I/O memory.
·Each component of a message is in the memory of the Communications Board. There-
fore, the CPU Unit can just execute the PMCR instruction to send or receive the data.
Therefore, there is no need to write ladder programs for the communications protocol.
CPU Unit
PMCR
instruction
D Step to Send and Receive Messages
·Sending and receiving messages as a single step includes step-type commands, such
as Send, Recv, Send & Recv, and Wait commands.
·The step can be finished or switched to another step according to the result of the step.
CPU Unit
PMCR
instruction
H Configuration of Protocol Macro Function
·The protocol consists of one or more sequences.
A sequence is an independent set of actions to perform together with a general-pur-
pose peripheral device, such as an Inverter. The RUN command and the frequency
reference are given to the Inverter and the status of the Inverter is read in a single
sequence, for example.
·A sequence consists of one or more steps.
Communications
Board
Communications
Board
Next process
according to
the result.
DSR message
Reception
Response
3G3MV
Chapter 7
3G3MV
Send
Step 0
To step n according to
the result.
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