137
Exchanging Data with the CPU Unit Section 3-3
Run status of CPU
Unit
The run status of the CPU Unit is reflected in ITEM007 to ITEM011 and
ITEM013 of the System Common block at all times. For this reason, the
required processing can be executed on the Loop Controller by the Step Lad-
der Program block (Block Model 301) or other blocks based on the contact
output of the System Common block.
CPU Unit run status in System Common block
To perform processing on
the Loop Controller
according to the run
status of the CPU Unit
To perform specific processing on the Loop Controller according to the run
status of the CPU Unit, use a Sequence Table or Step Ladder Program block
to perform the required processing taking the following run status (ITEM007 to
ITEM011, ITEM013) of the System Common block as the input conditions.
Example To indicate stop when the CPU Unit is in the PROGRAM mode
To forcibly stop running of the Loop Controller when the CPU Unit is in the
PROGRAM mode, input ITEM013 (PROGRAM mode) of the System Com-
mon block (Block Model 000) as the run status of the CPU Unit, and set
ITEM014 (run/stop command) of the System Common block to 0 (stop) by the
Loop Controller
System Common block
CPU Unit operating
status
CPU Unit
I/O memory
Auxiliary Area
A355 to A357 and A424
Loop Controller
operating status
Auxiliary Area
A608 and A 609
Loop Controller
command bits
ITEM 1 (ON) 0 (OFF)
007 Fatal error (fatal error detected by
system self-diagnostics or execu-
tion of FALS instruction)
Not fatal error
008 CPU Unit running (RUN mode or
MONITOR mode)
Stopped (PROGRAM mode or fatal
error)
009 Output OFF (Auxiliary Area A50015
turns ON.)
Not output OFF
010 RUN mode Not RUN mode
011 MONITOR mode Not MONITOR mode
013 PROGRAM mode Not PROGRAM mode
Loop Controller CPU Unit
System Common
block