10.3 List of Special Relays (COM Communication)10-1110.3 List of Special Relays (COM Communication)Only special relays related to communication by COM0 port of the main control unit and byCOM port of a communication cassette are listed below.WR900 (specification in word units)Relay No. Name DescriptionR900E(R9130) COM0 port communication error Turns ON when a communication error is detected during theuse of COM0 port(Note 1): The same function is also allocated to the special internal relay indicated in brackets.WR903 (specification in word units)Relay No. Name DescriptionR9030to R9031 Reserved for system -R9032(R9139) COM1 port operation mode flagTurns ON when the general-purpose communication functionis used.Turns OFF when functions other than general-purposecommunication are used.R9033 Print instruction active flag OFF: Instruction not activeON: Instruction in progressR9034 Program edit flag during RUNmodeA special internal relay that only turns on the first single scanfollowing the completion of rewriting during RUN.R9035to R9036 Reserved for system -R9037(R9138)COM1 port communication errorflagTurns ON when a transmission error occurs during datacommunication.Turns OFF when transmission is requested using an F159(MTRN) instruction.R9038(R913A)Reception done flag in COM1port general-purposecommunicationTurns ON when the terminator (end code) is received duringgeneral-purpose communicationR9039(R913B)Transmission done flag inCOM1 port general-purposecommunicationTurns ON when transmission is done during general-purposecommunication.Turns OFF when transmission is requested during general-purpose communication.R903Ato R903D Reserved for system -R903E(R9132)Reception done flag in COM0port general-purposecommunicationTurns ON when the terminator (end code) is received duringgeneral-purpose communicationR903F(R9133)Transmission done flag inCOM0 port general-purposecommunicationTurns ON when transmission is done during general-purposecommunication.Turns OFF when transmission is requested during general-purpose communication.(Note 1): R9030 to R903F changes even while a scan is in progress. The same function is also allocated to thespecial internal relay indicated in brackets.
