4
FUNCTIONS
Bus terminator
(Group 8)
4
- 9
4.1 PROFIBUS-DPV0 Functions
4.1.3 Global control function
(b) FREEZE, UNFREEZE
1) FREEZE
This service starts the FREEZE (input synchronization) mode.
In the FREEZE mode, the input status is refreshed every time a DP-Slave
receives the FREEZE service.
If no FREEZE service is received, the input status is held.
2) UNFREEZE
This service ends the FREEZE (input synchronization) mode.
Power
supply
module
(Group 3)
DP-Slave 1
DP-Slave 2
...
...
Input image memory data are refreshed at all times by polling.
...
<During UNFREEZE execution/Default>Actual input data are input to the input memory
without being changed. (Normal status)
...
<During FREEZE execution>Actual input data are input only once to the input image
memory at the timing of the FREEZE service.
...
FREEZE service (Issued within the same group)
...
Input to external device.
DP-Master (Class 1)
QJ71
QCPU
PB92V
FREEZE service is
sent to group 3.
(Group 3)
DP-Slave 3
...
Figure 4.7 FREEZE, UNFREEZE
(Group 3)
DP-Slave n
...
...
Bus terminator