Mitsubishi FX3U-232-BD User Manual page 520

FX Series PLC User's Manual - Data Communication Edition
Non-Protocol Communication (RS/RS2 Instruction)
2. Word devices
Device
ch1 ch2
D8063 D8438
D8400 D8420 Communication format setting This device sets the communication format.
D8402 D8422
D8403 D8423
D8405 D8425
D8409 D8429 Time-out time setting
D8410 D8430 Header 1 and header 2
D8411 D8431 Header 3 and header 4
D8412 D8432 Terminator 1 and terminator 2
D8413 D8433 Terminator 3 and terminator 4
D8414 D8434 Receiving sum (receive data) This device stores the received sum check value.
D8415 D8435
D8416 D8436 Sending sum
D8419 D8439 Operation mode display
R: Read only
R/W: Read or Write
12.4 Details of Related Devices (RS2 Instruction)
12.4.1 Serial communication error [M8063 and M8438]
These devices turn ON when an error occurs during serial communication.
1. Detailed contents
These devices work as serial communication error flags.
M8063 turns ON when an error occurs in serial communication using communication port ch1.
M8438 turns ON when an error occurs in serial communication using communication port ch2.
When M8063 turns ON, a corresponding error code is stored in D8063.
When M8438 turns ON, a corresponding error code is stored in D8438.
2. Cautions on use
The serial communication error flag does not turn OFF even after communication recovers its normal status.
Clear it by switching the PLC mode from STOP to RUN.
12.4.2 Sending wait flag [M8401 and M8421]
These devices remain ON while the PLC is waiting to send.
1. Detailed contents
M8401 remains ON while the PLC is waiting to send in communication using communication port ch1.
M8421 remains ON while the PLC is waiting to send in communication using communication port ch2.
• In full-duplex communication
While the control line is set to the standard or interlink mode in the communication parameter, when the
control line DR (DSR) turns OFF while sending data, the PLC waits to send and M8401 or M8421 turns
ON.
• In half-duplex communication
When the sending request device is set to ON while data is being received, the PLC waits to send and
M8401 or M8421 turns ON.
F-82
Name
Serial communication error
code
Amount of remaining send
data
Amount of data already
received
Communication parameter
display
Receiving sum (calculation
result)
Description
When the serial communication error flag turns ON, this device
stores the corresponding error code.
This device stores the amount of remaining send data.
This device stores the amount of data already received.
This device stores communication parameters set in the PLC.
This device sets the timeout time.
These devices set the headers 1 to 4.
These devices set the terminators 1 to 4.
This device stores the sum check value calculated from the
received data.
This device stores the sum check value added to the send
data.
This device stores the communication type being used.
12 Related Data
12.4 Details of Related Devices (RS2 Instruction)
R/W
R/W
R/W
R
R
R
R/W
R/W
R/W
R/W
R/W
R
R
R
R