Mitsubishi Electric A1SJ71DN91 User Manual page 28

3. SPECIFICATIONS
Message communication
request (Y(n+1)2)
Message communication
complete (Xn2)
Message communication
error signal (Xn5)
FROM/TO
(3) Message communication complete
Message communication error signal
Message communication request
These signals are used for message communication.
conducted if the status of the master communication status area in buffer memory is
"operation in progress."
(a) Follow the procedure below to conduct message communication.
1) Write the message communication data to the message communication
command area in buffer memory.
2) Turn ON message communication request (Y(n+1)2) with a sequence program.
(Set the interval of turning ON the message communication request at 100 ms
or over.)
(b) The message communication completes with the results written onto the "Message
communication results" area, and the message communication complete (Xn2)
turns ON.
(c) Check the results of the message communication through the message
communication error signal (Xn5).
(d) After reading the communication data with FROM command, the sequence program
is used to turn OFF the message communication request (Y(n+1)2).
The message communication complete (Xn2) and message communication error
signal (Xn5) automatically turns OFF.
Write message
communication
command (TO
instruction)
(For data send only)
(4) Error set signal: Xn3, Error reset request: Y(n+1)3
These signals are used to notify an error and reset error codes.
(a) If an error occurs, error information is stored in the error information area in buffer
memory and the error set signal (Xn3) turns ON.
The error set signal automatically turns OFF when the cause of the error is
removed.
(b) Once the cause of error is removed, turning ON the error-resetting request
(Y(n+1)3) with the sequence program clears the error code set on the "error
information" area.
Error reset request (Y(n+1)3)
Error set signal (Xn3)
FROM/TO
: Xn2
: Xn5
: Y(n+1)2
Write message
communication
data (TO
instruction)
−
3 6
MELSEC-A
Message communication is
Error involved
No error
Read message Read message
communication communication
results (FROM data (FROM
instruction) instruction)
(For data receive only)
Read error
information (FROM
instruction)