Panasonic AF7CPS Series User Manual page 65

KEY POINTS

The data without the Code STX at the reception is saved in the reception
buffer, and the "reception done" flag turns on when the end code is
received.

However, if the code STX is added in the middle of the data, the data are
saved from the beginning of the reception buffer.
Sending process: Sending done flag and GPSEND instruction are related as follows:
Transmitted
data
SCU
send buffer
GPSEND
instruction
execution
General-purpose

communication

Sending active flag
Y8
 Header (STX) and terminator (ETX) are automatically added to the data to be sent. The data
are transmitted to an external device.
 After GPSEND instruction is executed, data transmission is started in several μs to several
tens of ms. For time before transmission is started, please refer to the communication cycle
time (SM208-SM210) using the system monitor function.
 After GPSEND instruction is executed, dual sending to the same port is not possible until the
"sending general-purpose communication flag" (Y8) turns OFF.
 The "General-purpose communication Sending active flag" (Y8) turns OFF in GPSEND
instruction execution in the next scan or later following completion of data sending to an
external device. The "General-purpose communication Sending active flag" (Y8) always
remains on for at least 1 scan time.
a
ETX
STX b
STX STX STX STX
a a a a
b b b b
ETX ETX ETX ETX
6.4 Sending/Receiving Flag Operation
STX c d
STX STX STX
c c c
d d d
e e e
ETX ETX ETX
e ETX
STX STX
c c
d d
e e
ETX ETX
ON
OFF
ON
OFF
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