9DEDICATED INSTRUCTIONS

Error

MELSEC-Q

(1)In case of operation errors, the error flag (SM0) turns on and the error code is stored in SD0.

See one of the following manuals according to the error code, and check and correct the error.

<Error code>

4FFFH or less : QCPU(Q Mode) User's Manual

(Hardware Design, Maintenance and Inspection)

Program example

The following example shows a program that receives any data using the bidirectional protocol and stores that data in D10 or later.

The input/output signals of the Q series C24 are from X/Y00 to X/Y1F:

Designate the receive channel.

Clear the receive data count storage device to 0.

Designate the allowable receive data count.

With the normal completion, the receive data within the allowable receive data count (user designated) is read from the receive data storage area in the buffer memory.

• After the BIDIN instruction is executed, the user designated read completion signal (M0) comes on for 1 scan.

• The reading of received data is performed by the PLC CPU.

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