Download MG40 Series

3-3. CC-Link Command Transmission Sequences
These steps are taken to transmit the commands using the CC-Link interface and acquire the response.
IRY
(PLC→MG41-NC)
0
1
0
Command setting
completed
IRX
(MG41-NC→PLC)
Response
received
0
PLC receive buffer
(MG41-NC→PLC)
Command setting
completed
1
Command execution
completed
MG41-NC receive buffer
(PLC→MG41-NC)
1
0
Response
reception check
0
Response
received
1
Command execution
completed
Command
Command response
0
Response
reception check
Next command
Next command response
The sequence is as follows when viewed from the PLC side.
1
The command is written into the transmit buffer.
2
“1” is set for IRY. (The execution of the command is instructed.)
3
The PLC waits for IRX to be set to “1.” (The PLC waits for the command execution to be completed.)
4
When IRX is set to “1,” the command response is acquired.
5
When the response is acquired, IRY is set to “0.” (The response is received.)
6
The PLC waits for IRX to be set to “0.” (The PLC waits for the response reception to be checked.)
The sequence is as follows when viewed from the MG41-NC main unit side.
1
“1” is set for IRY, and command execution is instructed.
2
The command is read from the buffer, and it is executed.
3
The response is written in the buffer, and “1” is set for IRX. (The command execution is completed.)
4
The MG41 waits for IRY to be set to “0.” (The MG41 waits for the response to be received.)
5
“0” is set for IRX. (The MG41 checks that the response has been received.)
MG40 Series
(E) 3-3