Siemens SIMATIC ET 200SP - Page 160

Using the SSI_Absolute_Encoder technology object
4.5 Programming the SSI_Absolute_Encoder
Counting, measurement and position detection
Function Manual, 12/2017, A5E32009889-AG
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Parameter changes via the user program
Proceed as follows to modify parameters using the user program:
1. Check the relevant Set tag to establish whether the technology object is ready for the
parameter change (Set tag = FALSE) or whether a change job is still running (Set tag =
TRUE).
The following Set tags in UserCmdFlags are available for this in the static tags of the
technology object instance DB:
– SetReferenceValue0
– SetReferenceValue1
2. If the technology object is ready for the parameter change, modify the relevant static tag.
The following static tags of the technology object instance DB are available for this:
– NewReferenceValue0 / NewReferenceValue0_M (for SetReferenceValue0)
– NewReferenceValue1 / NewReferenceValue1_M (for SetReferenceValue1)
3. Set the relevant Set tag for execution of the change job.
4. Use the output parameter Error to check whether an error has occurred.
If no errors have occurred and the Set tag has been automatically reset by the technology
object, the parameter change was successful.
Operating mode
Configure the operating mode in the technology object under "Behavior of DQ0".
The operating mode is indicated by the output parameters CompareMeasuredValue:
State
Description
FALSE Operating mode "Use position value (SSI absolute value) as reference":
The comparison functions work with the position value. The following static
variables are specifically used in this operating mode:
• NewReferenceValue0
• NewReferenceValue1
• CurReferenceValue0
• CurReferenceValue1
The four specific static variables of operating mode "Use measured value as
reference" are ignored.
TRUE Operating mode "Use measured value as reference":
The comparison functions work with the measured value. The following static
variables are specifically used in this operating mode:
• NewReferenceValue0_M
• NewReferenceValue1_M
• CurReferenceValue0_M
• CurReferenceValue1_M
The four specific static tags of operating mode "Use position value (SSI abso-
lute value) as reference" are ignored.