Siemens SIMATIC ET 200S Operating Instructions Manual page 210

1Count5V/500kHz
3.8 Position feedback
Acknowledgment Principle in Isochrone Mode
In isochrone mode, 4 or 6 bus cycles are required to reset the status bits and to accept
values during the load function in this mode.
Figure 3-43
Error Detection
The program errors must be acknowledged. They have been detected by the
1Count5V/500kHz and are indicated at the feedback interface. A channel-specific diagnosis
is carried out if you have enabled group diagnostics in your parameter assignment (see the
ET 200S Distributed I/O System
The parameter assignment error bit is acknowledged by means of correct parameter
assignment.
Figure 3-44
In the case of continuous error acknowledgment (EXTF_ACK=1) or at CPU/Master Stop, the
1Count5V/500kHz signals errors as soon as they are detected and deletes them as soon as
they have been eliminated.
210
Acknowledgment Principle in Isochrone Mode
Manual).
Error Acknowledgment
Technological Functions
Operating Instructions, 02/2007, A5E00124867-05