Comparison Values; Comparison Values And Outputs - Siemens SIMATIC ST-1500 Function Manual

2.2 Basics of counting, measuring and position input (TM Count, TM PosInput, Compact CPU)
2.2.8

Comparison values

2.2.8.1

Comparison values and outputs

Description
You can specify two comparison values to control both digital outputs of the channel
independently of the user program:
● Comparison value 0 for digital output DQ0
● Comparison value 1 for digital output DQ1
Depending on the operating mode and the encoder used, define two position, counter or
measured values as comparison value. Comparison value 1 must be greater than
comparison value 0. The comparison values are configurable and can be modified during
runtime using the user program.
Note
DQ0 of a counter of a Compact CPU
With a Compact CPU, the respective digital output DQ0 is available via the feedback
interface, but not as a physical output.
Switching digital outputs from the user program
The control bits (Page 185) TM_CTRL_DQ0 and TM_CTRL_DQ1 are used to control use of
the digital outputs.
If TM_CTRL_DQm is set to 0, you can control the relevant digital output from the user
program with the control bit SET_DQm regardless of the configured technological function. If
TM_CTRL_DQm is set to 1, the technological function of the controller of the respective
digital output is enabled.
The status of a digital output is indicated by the respective STS_DQm feedback bit.
Counting, measurement and position detection
Function Manual, 12/2017, A5E32009889-AG
The basics of counting, measurement and position detection
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