Mitsubishi Electric FX5 User Manual page 160

Sending wait flag
These devices remain ON while the PLC is waiting to send.
FX5 dedicated
CH1 CH2
SM8560 SM8570
R: Read only
• For RS-232C
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 sending wait flag turns ON.
• For RS-485
The sending wait flag does not turns ON.
Precautions
When setting these devices to ON, set the drive condition with a pulse.
Send request flag
When these devices are set to ON by SET instruction, the PLC starts to send. When sending of the data is completed, the
sending request flag is automatically reset.
FX5 dedicated
CH1 CH2
SM8561 SM8571
R/W: Read/Write
Precautions
When setting these devices to ON, set the drive condition with a pulse.
Receiving completed flag
Receiving completed flag turns ON when receiving is completed. When these devices turn ON, data cannot be received.
FX5 dedicated
CH1 CH2
SM8562 SM8572
R/W: Read/Write
Receiving is completed in one of the following three conditions.
• When the PLC receives the amount of receive data specified by the RS2 instruction
• When the terminators are set, and the PLC receives the code set by the terminator
• When data receiving is suspended and the PLC does not receive the next set of data within the time set by the time-out
time setting device
When the receiving completed flag turns ON, transfer the received data to another storage destination, and then set this flag
to OFF.
When this flag is set to OFF, the PLC waits to receive.
Precautions
When the RS2 instruction is driven while the amount of receive data is set to "0", the PLC does not wait to receive. To make
the PLC wait to receive, it is necessary to set the amount of receive data to "1" or more and set the receiving completed flag
ONOFF.
5 NON-PROTOCOL COMMUNICATION
158
5.9 Related Devices
FX3 Series
compatible
CH3 CH4 CH1
SM8580 SM8590 SM8401
CH3
SM8581
CH3
SM8582
Description
CH2
SM8421 These devices turn ON when serial communication is
waiting to send.
Description
CH4
SM8591 When set to ON, serial communication data sending
starts. Set to ON with the SET instruction.
Description
CH4
SM8592 These devices turn ON when serial communication
data receiving is complete.
R/W
R
R/W
R/W
R/W
R/W