Communication With External Devices - Panasonic FP E Series User Manual

7.5.2 Communication with External Devices

Programming example of general-purpose serial communication
The F159 (MTRN) instruction is used to send and receive data via the specified COM port. F159 (MTRN)
is only used with the FPΣ. It is an updated version of F144 (TRNS) and allows multiple communication
ports to be accommodated.
F144 (TRNS) is not available with the FPΣ.
F159 (MTRN) instruction
Data is sent and received via the specified COM port .
Devices that can be specified for S:
Devices that can be specified for n:
Devices that can be specified for D:
Transmission of data
The amount of data specified by n is sent to the external device from among the data stored in the data
table, starting with the area specified by S, through the COM port specified by D. Data can be sent with
the header and terminator automatically attached. A maximum of 2048 bytes can be sent. When the
above program is run, the eight bytes of data contained in DT101 to DT104 and stored in the send buffer
starting from DT100 are sent from COM1 port.
Reception of data
Reception of data is controlled by turning the "reception done" flags R9038/R9048 on and off. The
received data is stored in the receive buffe specified in the system register. Data can be received when
F159 (MTRN) turns the "reception done" flag off. When the reception of the data is completed (the
terminator is received), the "reception done" flag turns on, and subsequently, receiving data is prohibited.
To receive the next data, execute the F159 (MTRN) instruction and turn the "reception done" flag off to
clear the number of received bytes to 0. To receive data continuously without sending data, clear the
number of transmitted bytes to 0 (set "n" to "K0"), and then execute the F159 (MTRN) instruction.
Only data registers (DT) can be specified as the send buffer.
WX, WY, WR, WL, SV, EV, DT, LD, I (I0 to ID), K, H
Only the K constants (only K1 and K2)
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