Panasonic AF7CPS Series User Manual page 59

 Timing chart
 Data received from an external device are saved in the same reception buffer.
 When the terminator (end code) is received, the "reception done" flag (X0) turns on.
Subsequently, the following data are saved in the buffer upon reception. 8 data can be
received consecutively.
Received data
Reception
done flag
X0
GPRECV
execution
condition R100
 When the GPRECV instruction is executed, data are copied into the specified area, and the
reception done flag (X0) turns OFF. The reception done flag (X0) turns OFF when the I/O
refresh is executed at the beginning of the subsequent scans.
Reception buffer
Received data
Reception done flag
(X0)
Execute GPRECV
 Saving method for received data
When data are saved in a given data register from the reception buffer, based on GPRECV
instruction, the data are saved in the following manner.
U5
DT200
DT201 H32(2)
H34(5)
DT202
-----
DT203
-----
DT204
-----
-----
Start receiving
1 2
・・・
Cr
Saves the received No. of bytes.
H31(1)
The received data are saved in ascending order from
H33(3)
lower bytes.
H35(4)
If the received No. of bytes is smaller than the area specified
-----
by the GPRECV command, the data are not overwritten.
-----
5 ( C ) A
R
Execute GPRECV instruction
Cr
6.3 Receiving Operation
B
・・・
ON
OFF
ON
OFF
Reception done flag (X0):
When reception has been done: ON,
When copying of received data has
been done based on GPRECV
instruction: OFF
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