Receive Data Clear - Mitsubishi Melsec-L Series User Manual

11.1.5 Receive data clear

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(2) Confirmation using GX Works2, display unit and indicator LED of
C24
The following shows how to confirm the errors.
GX Works2
Display unit
Indicator LED of C24
(3) Precautions
The following shows the precautions of receive data when a reception error
occurs.
1) All of the receive data for which an error was detected is ignored and a
response message indicating an abnormal completion (NAK message) is
sent to the external device.
If an error has been detected when receiving the message, the C24 does
not send the reception data read request to the CPU module.
2) The receive area in the buffer memory will contain the data received normally
just prior to the error occurrence. (Data will not be rewritten.)
Data communications using the bidirectional protocol must be performed after a
response message is received in reply to the preceding data transmission.
If the C24 detects an error while receiving data, it sends an NAK message (response
message) to the external device after the data reception completion and ignores the
data being received when the error was detected.
Therefore, the receive data does not have to be cleared.
11 DATA COMMUNICATION USING THE BIDIRECTIONAL PROTOCOL
Item
"Module's Detailed Information" screen
"Error History" screen
"Intelligent Function Module Monitor"
screen
Buffer memory monitor
ERR LED turns on
Reference
Chapter 15
Chapter 15
GX Works2 Version1
Operating Manual
(Common)
MELSEC-L CPU Module
User's Manual (Function
Explanation, Program
Fundamentals)
Chapter 15
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