Panasonic FP7 Series User Manual page 153

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I/O allocation (For Serial Communication Unit)
COM. port no.
1 2 3
X0 X1 X2
X4 X5 X6
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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, X1, X2, X3) turns
on. Subsequently, the following data are saved in the buffer upon reception. 8 data can be
received consecutively.
● When the GPRECV instruction is executed, data are copied into the specified area, and the
reception done flag (X0, X1, X2, X3) turns OFF. The reception done flag (X0, X1, X2, X3)
turns OFF when the I/O refresh is executed at the beginning of the subsequent scans.
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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.
WUME-FP7COM-07
Name
4
General-purpose
X3 communication Reception
done flag
General-purpose
X7 communication Reception
copy done flag
9.4 Receiving Operation
Description
Turns ON when the receiving process is completed in
the general-purpose communication mode.
Turns ON when the GPRECV instruction is executed
and the received data have been copied into the
specified operation memory. Turns OFF when there
are no applicable data.
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