Advertisement
4. LINKING TO THE AnACPU (WITH DEDICATED INSTRUCTIONS)
AND THE AJ71 PT32-S3
MELSEC-A
(3) Though the execution command of the FROM instruction is set t o ON,
the next FROM instruction information is not stored in the request-to-
communicate registration areas until the processing
of the FROM in-
struction being executed is completed and the execution-completed flag
designated by the PRC instruction goes ON. Thus,
it
is not necessary
to provide an interlock that allows the FROM instruction to be executed
only after the execution-completed flag goes ON,
I
LEDR
Request-to-
communicate
registration area
-
The FROM instruction
- - - - - -
information executed in
Device for execution.
completed flag
(4) For
communications with
the remote terminal modules linked to an
AJ71 PT32-S3, always turn the AJ71 PT32-S3 communications start sig-
nal Y(n+28) ON before executing each instruction. If the communica-
tions start signal is not turned
ON, communications processing cannot
be done.
Even though the M I N I 4 3 instruction is executed when the communica-
tions start signal is OFF, no
error will occur. However, the bit devices
designated with m l of [PRC][ml][m2] will not go ON.
(5)
When the reset switch on the front of an A64RDC is moved to reset, the
A64RDC returns
to the initial state and performs conversion with
defaults.
Set the sequence program
to continuously monitor the reset switch
ON-detected flag (X5) and, when the flag is turned ON, to clear the
request-to-communicate registration areas and
to write initial setting
data to the A64RDC again (when executed with other than defaults).
A64RDC reset operation
Reset switch ON-detected
flag (X5)
Reset switch ON-detected
flag reset signal (Y5)
After this, initial setting data is
again written to the A64RDC
buffer in scans.
Request-to-communicate registration
areas are cleared when both (X5) and
(Y5) are turned ON.
Part (6) of this section explains the
clearing procedures.
4-30
Advertisement
