NAiS FP Series, User Manual

Page: 203 / 326

FP
Σ
Communication Function 2 General-purpose Serial Communication
9 - 36
When sending data:
Relationship between the various flags “Reception done flag and Transmission done
flag” and the F159 (MTRN) instruction
b
a
b
a
<2> <1> <2> <1> <0>
b
a
<0>
b
a
<0>
d
e
c
<3>
STX ETX ETX STX
a
b
c
d e
<0>
on
off
on
off
d
e
c
d
e
c
d
e
c
d
e
c
Transmission Transmission
F159 (MTRN)
instruction
execution
Transmission
done flag
“R9039 or R9049”
Transmission buffer
Number of bytes not
yet transmitted
Duplex transmission
disabled while F159
(MTRN) instruction
is being executed
Transmitted data
* : Transmission point
Figure 199: FP
Σ
Flag operation when sending data (STX and ETX setting)
Start code (STX) and end code (ETX) are automatically added to the data being
transmitted, and the data is transmitted to an external device.
When the
F159 (MTRN) instruction is executed, the transmission done flag “R9039 or
R9049” go off.
Duplex transmission is disabled while the
F159 (MTRN) instruction is being executed.
Check the transmission done flag “R9039 or R9049”.