Mitsubishi Electric MELSEC iQ-R Series User Manual page 69

Flow of RTR response
The following is the procedure of receiving an RTR and sending response data.
Follow this procedure when sending response data manually.
Control by the program
Bit of the
'Layer 2 RTR flags'
corresponding
(Un\G8350 to Un\G8352)
message slot
Transmit buffer
Frames on the network
 When the RJ71CN91 receives an RTR, the bit for the corresponding message slot in 'Layer 2 RTR flags' (Un\G8350 to Un\G8352) turns on.
 Check via the program whether there is any message slot for which the bit is turned on in 'Layer 2 RTR flags' (Un\G8350 to Un\G8352).
 If there is any message slot for which the bit is turned on in 'Layer 2 RTR flags' (Un\G8350 to Un\G8352), send data of the corresponding message slot via
the program. ( Page 63 Flow of data transmission)
 When the data is sent from the corresponding message slot, the bit for the corresponding message slot in 'Layer 2 RTR flags' (Un\G8350 to Un\G8352) turns
off.
To receive , the RJ71CN91 module must be in online mode.
'Layer 2 online mode status' (X3) is turns on when 'Layer 2 online mode request' (Y3) is turned on in advance.
(The state must be in Layer 2 online mode during network connection except when parameter change work is
performed.)
RTR response timing
For automatic data transmission, response data is sent automatically when an RTR is received.
For manual data transmission, the RTR response timing is the same as the data transmission timing. ( Page 64 Data
transmission timing)
Ò
Receive RTR
Ó
MOV/FROM instruction
ON
OFF
Ô
Data transmission executed
OFF
Transmit data
Data transmission
Õ
executed
Transmit data
1.11 Layer 2 Message Transmission and Receive
1
1 FUNCTIONS
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