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2 Instructions
CP1E CPU Unit Instructions Reference Manual(W483)

Serial Communication

Instructions
2

TXD

Programming Example

If CIO 0.01 turns ON while the RS-232C Port Send Ready Flag (A392.05) is ON, three bytes of data

starting from the upper byte of D10 are sent without conversion to the Code Reader connected to the

CPU Unit’s built-in RS-232C port. These three bytes contain “@GO”, which is the normal read com-

mand used as a trigger input to the Code Reader from the RS-232C line.

Controlling Signals
4 E 00
4 0 35
15 8 71112 340
S: D10
@TXD
D10
D20
0.01 A392.05
S
C
&3N
RS-232C Port Send
Ready Flag
D11
@RXD
D100
D20
0.02 A392.06
A393
RS-232C Port Receive
Ready Flag
RS-232C Port
Reception Counter
Always #0.
Serial Port Specifier
#1: CPU Unit’s built-in RS-232C port
0 1 00
15 8 71112 340
C: D20
RS and ER Signal Control
#0: No RS and ER signal control.
Byte Order
#0: Most significant bytes first
Three bytes
Lower byte
Upper byte
40 53 4E ED
Sent @ G L
TXD
D300
D400
0.01
S
C
&0N
0 1 03
15 8 71112 340
C: D400
0
15 1314 12
S: D300
Turns OFF ER signal.
001
Turns ON RS signal.
Always #0.
Serial Port Specifier
#1: CPU Unit’s built-in RS-232C port
RS and ER Signal Control
#3: RS and ER signal control
Byte Order
#0: Most significant bytes first
When CIO 0.01 turns ON, the
status of bit 15 of D300 is output
as the RS signal and the status
of bit 14 is output as the ER
signal.