Siemens SIMATIC ST-1500 Function Manual page 190

Notes on the feedback bits
Feedback bit
ENC_ERROR
EVENT_CAP
EVENT_CMP0
EVENT_CMP1
EVENT_OFLW
EVENT_SYNC
EVENT_UFLW
EVENT_ZERO
LD_ERROR
Counting, measurement and position detection
Function Manual, 12/2017, A5E32009889-AG
Notes
This bit indicates that one of the following errors has occurred at the encoder signals (retentive)
for the respective technology module:
TM Count:
Wire break of digital input A, B, or N (with push-pull encoder)
•
Invalid transition of A/B signals (with incremental encoder)
•
TM PosInput:
Invalid transition of A/B signals (with incremental encoder)
•
RS422/TTL error
•
SSI encoder error or SSI frame error (with SSI absolute encoder)
•
If you have enabled the diagnostic interrupts, the respective diagnostic interrupt is triggered in
the event of encoder signal errors. For information on the meaning of the diagnostic interrupts,
refer to the manual for the respective technology module.
The bit is reset once you have acknowledged the error with RES_ERROR .
This bit indicates that a Capture event has occurred and a counter value has been saved in
CAPTURED_VALUE . You reset the status by resetting EN_CAPTURE .
This bit indicates the saved status that a comparison event (status change) has occurred for
the digital output DQ0 based on the selected comparison condition. You reset the status by
acknowledgment with RES_EVENT.
If the counter value is set to the start value in counting mode, EVENT_CMP0 is not set.
This bit indicates the saved status that a comparison event (status change) has occurred for
the digital output DQ1 based on the selected comparison condition. You reset the status by
acknowledgment with RES_EVENT.
If the counter value is set to the start value in counting mode, EVENT_CMP1 is not set.
This bit indicates the saved state which shows that there was a counter value overflow. You
reset the status by acknowledgment with RES_EVENT.
This bit indicates the saved status for which the counter was loaded with the start value by an
external reference signal (synchronization) when using an incremental or pulse encoder. You
reset the state by resetting EN_SYNC_UP or EN_SYNC_DN .
This bit indicates the saved state which shows that there was a counter value underflow. You
reset the status by acknowledgment with RES_EVENT.
This bit indicates the saved status with which the counter value or position value experienced a
zero crossing. You reset the status by acknowledgment with RES_EVENT.
This bit indicates that an error occurred (latching) during loading via the control interface. The
loaded values were not applied. When using an incremental or pulse encoder, one of the fol-
lowing conditions is not fulfilled:
Low counting limit <= counter value <= high counting limit
•
Low counting limit <= start value <= high counting limit
•
Low counting limit <= comparison value 0/1 <= high counting limit
•
Comparison value 0 < comparison value 1
•
When using an SSI absolute encoder, one of the following conditions is not fulfilled:
0 <= position value <= maximum position value
•
0 <= comparison value 0/1 <= maximum position value
•
Comparison value 0 < comparison value 1
•
The bit is reset once you have acknowledged the error with RES_ERROR .
Using the module
5.1 Using the technology module
189