Mitsubishi Electric MELSEC iQ-R Series User Manual page 202

General procedure
This section explains the general procedure for nonprocedural protocol/bidirectional protocol (executed in full-duplex
communication) data communication using the modem function between the CPU modules with C24 installed.
■System configuration
Station A
RS-232
cable
■General procedure
1.
Perform initial setting for C24 at both station A and station B.
2.
Perform modem/TA initialization on station B.
3.
Perform modem/TA initialization and line connection on station A.
4.
Communicate data using the nonprocedural protocol/bidirectional protocol.
5.
In order to end the communication, disconnect line from station A that initiated the line connection.
■Processing flow
Station A
(connection request side)
Connection Y11
request
Modem initialization X10
completion
Connecting X12
Disconnection Y12
request
Disconnection X14
completion
RS-232 CD terminal
Station B
(connection reception side)
Modem initialization X10
completion
Connecting X12
Disconnection Y12
request
Disconnection X14
completion
RS-232 CD terminal
7 COMMUNICATIONS BY THE MODEM FUNCTION
200
7.4 Startup of the Modem Function
Public line
Modem
Connection
(ON)
* It is possible to disconnect line from Station B, as well.
Station B
Modem
RS-232
cable
Communication Disconnection
(OFF)
(OFF)