Mitsubishi Electric MELSEC iQ-RJ71C24-R4 - Page 287

15 DATA COMMUNICATIONS USING USER FRAMES
15.2 Data Reception
285
15
Timing chart for reception processing of C24
The charts indicating the timing of the reception processing for data reception using a user frame, including the reception
processing by the receive end data quantity, are shown below.
The numbers in the table indicate the timing of a received data read request to the CPU module.
*1 The reception processing by the receive end code is not performed when the same data as the receive end code has been registered in
the final frame.
*2 The data reception interval is not monitored with the no-reception monitoring time (timer 0) when only the final frame is set.
When a reception error is detected, C24 stores arbitrary data portion of the data received immediately before
the error in the receive area on the buffer memory, then turns the 'CH1 reception abnormal detection' (X4) ON.
Combination Amount of received data of
arbitrary data
Timing pattern number
Received data
Received
data prior to
the
reception of
the start
frame
When
receiving the
start frame
When receiving
arbitrary data in
the reception
message
When
receiving the
final frame
When receiving
the end code
*1
Combi
nation
with
the
start
frame
1-A Receive data quantity < receive
end data quantity
Deleted Data reception
start
 1-A(1) Data of the end code
is treated as part of
arbitrary data.
Receive data quantity  Receive
end data quantity
1-A(2)
1-B Receive data quantity = 0  1-B 
1-C Receive data quantity  Receive
end data quantity
1-C(1)  Data of the end code
is treated as part of
arbitrary data.
Receive data quantity > Receive
end data quantity
1-C(2)
1-D Receive data quantity
Method 1 dedicated receive end
data quantity > 0
1-D
1-E Receive data quantity
Method 1 dedicated receive end
data quantity = 0
Data
recepti
on start
1-E 
Combi
nation
without
the
start
frame
2-A
*2
Receive data quantity < Receive
end data quantity
Data reception start 2-A(1) 2-A(3)
Receive data quantity  Receive
end data quantity
Data
recepti
on start
2-A(2) 2-A(4)
2-B
*2
Receive data quantity = 0  Data
reception
start
2-B 