Technical data

11.3 Activities at Checkpoints
The table below shows you which activities of the PG functions are
executed at the checkpoints.
Activities of the online
functions
System checkpoint
User
check-
point
"Stop" "Cycle" "Wait
state"
"Asyn-
chronous
"
Input of the address:
write data
1)
Block input:
declare block as valid
Delete block
Compress memory:
shift blocks
1) 2)
START/STOP
OVERALL RESET
STATUS: read and output data
STATUS VARIABLES: read
and output data
PROGRAM TEST:
preset breakpoints
read and output data
FORCE (process interface modules)
1)
FORCE VARIABLE
1)
*
*
*
*
3)
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
1)
Activities distributed over more than 1 system checkpoint
2)
Maximum one block per system checkpoint
3)
After compressing the memory in STOP, only COLD RESTART permitted.
Table 11-2 Activities at checkpoints
Activities at Checkpoints
CPU 928B Programming Guide
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