7-138
7.9 Display Instructions
7.9.2 Printing comments
PRC
(2) Output signals from the output module are transmitted at the rate of 30ms per character.
For this reason, the time required to complete the transmission of the number of specified
characters will be 30ms n (ms).
At 10ms interrupt intervals, the PRC instruction executes data output, strobe signal ON, and
strobe signal OFF. The other instructions are executed continuously during a period
between the above processes.
(3) In addition to the ASCII code data, the output module also outputs a strobe signal (10ms
ON, 20ms OFF) from the
+ 8 device.
(4) Following the execution of the PRC instruction, the PRC instruction execution flag (
+ 9
device) remains ON until the completion of the transmission of the number of specified
characters.
(5) The PRC instruction can be used multiple times, but it is preferable to set the interlock with
the PRC instruction execution flag (
+ 9 device) so that they will not be ON
simultaneously.
(6) If no comments have been registered to the device specified for
, processing will not be
performed.
(7) When a comment is read, SM720 turns ON for one scan after the instruction is completed.
SM721 turns ON during the execution of the instruction.
The PRC instruction cannot be executed while SM721 is ON. If an attempt is made, no
processing is performed.
1. For device comments used in the PRC instruction, use comment files stored in
the memory card.
Comment files stored in the internal memory cannot be used.
2. The comment file used in the PRC instruction is set at the "PLC File Setting"
option in the parameter mode.
If no comment file has been set for use by the PLC file setting, it will not be
possible to output device comments with the PRC instruction.
3. Do not execute the PRC instruction during an interrupt program.
Otherwise, malfunction may occur.
S
tro
b
e
s
i
gna
l
OFF
ON
30
ms
10
ms
10
ms
10
ms
10
ms
10
ms
Data
output
E
xecut
i
on
of
sequence
program
Process
i
ng
of
P
RC i
nstruct
i
on
d
d
d
s
Summary of Contents for MELSEC Q Series
Page 1: ...Structured Programming Manual Mitsubishi Programmable Controller QCPU Common Instructions ...
Page 2: ......
Page 14: ...A 12 MEMO ...
Page 340: ...6 178 MEMO MTR ...
Page 708: ...7 368 MEMO ...
Page 776: ...8 68 MEMO ...
Page 796: ...9 20 MEMO ...
Page 804: ...App 8 MEMO ...
Page 812: ...Index 8 MEMO ...
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