NAiS FP Series User Manual page 182

FPΣ
Tip
To perform repeated reception of data, refer to the following steps.
1. Receive data
2. Reception done (R9038/R9048: on, reception prohibited)
3. Process received data
4. Execute F159(MTRN) instruction (R9038/R9048: off, reception possible)
5. Receive subsequent data
Preparation of reception
The reception done flag "R9038(R9048)" turns on when data reception from the
external device is completed. Reception of any further data is prohibited.
To receive subsequent data, you must execute an F159(MTRN) instruction to turn
off the reception done flag "R9038(R9048)".
R0
F159 MTRN, DT100, K 0, K 1
To repeatedly perform only reception, specify K0.
R9038(R9048) also turns off when transmission is performed
with a byte number specification.
* The contact numbers in parentheses indicate COM. 2 port contacts.
9.2 Overview of Communication with External Devices
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