Siemens SIMATIC ST-1500 Function Manual page 90

Not setting between comparison value 0 and comparison value 1
The respective STS_DQ feedback bit is set to 1 when:
Comparison value 0 <= counter value <= comparison value 1
Counting, measurement and position detection
Function Manual, 12/2017, A5E32009889-AG
The basics of counting, measurement and position detection
2.4 Basics of counting (digital input modules)
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