Yaskawa MP920 Communications Module - Manual (Page 45)

3.3 Sample Programming Example
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3.3 Sample Programming Example
This section shows an example of a ladder logic program used to implement the message func-
tion. It also explains the relationship between the communications protocol and the message
function.
For message transfers, it is necessary to clearly recognize whether the system operates as a Mas-
ter or Slave. In the sample program given below, only the basic part of the ladder logic program
used for the system functions is coded.
Refer to Appendix A System Functions for the detailed function parameters.
3.3.1 Master Function
The Master uses the send message function (MSG-SND). Messages are sent to the Slave, and
a response is received.