Transmission Error Detection And Check Methods - Mitsubishi Electric MELSEC iQ-R Series User Manual

Transmission error detection and check methods

The following explains how to detect and confirm errors that may occur when transmitting data to target devices.
The following items are considered as the primary causes of errors that may occur during data transmission.
Cause of transmission error
A transmission error occurred due to noise.
A timeout occurred for the no-reception monitoring time (timer 0).
A timeout occurred for the response monitoring time (timer 1).
A timeout occurred for the send monitoring time (timer 2).
Data that could not be converted with the ASCII-BIN conversion was included.
The send data quantity that exceeded the send area size was designated.
Simultaneous transmissions occurred.
Confirmation using a program
■Detecting a transmission error
The following device and input signal turn ON.
• BIDOUT instruction completion device + 1
• 'CH Error occurrence' (XE/XF)
■Confirming a transmission error
The transmission error code can be checked using the BIDOUT instruction control data ((S1) + 1).
Or, it can be checked by reading the 'data transmission result' (Un\G599/615).
For details on how to check the error code contents and corrective actions, refer to the following section.
Page 473 Error Code List
Confirmation using the module and Engineering tool
■Confirmation using the indicator LED
When C24 detects an error, including a reception error, the ERR LED turns ON.
■Confirmation using Engineering tool
Monitor the 'data transmission result' (Un\G599/615) to check the error code.
Reference
MELSEC iQ-R Serial Communication Module
User's Manual (Startup)
Page 228 No-reception Monitoring Time (timer 0)
Setting
Page 231 Response Monitoring Time (timer 1)
Setting
Page 233 Send Monitoring Time (timer 2) Setting
Page 359 ASCII-BIN Conversion for Data
Communicated with Bidirectional Protocol
Page 97 Send area and send data arrangement
Page 104 Processing when Simultaneous
Transmission is Performed during Full-Duplex
Communications
4 DATA COMMUNICATION USING BIDIRECTIONAL PROTOCOL
4.2 Transmitting Data to Target Device
4
103