Siemens SIMATIC S5 Manual page 25

Standard Function Counter
Cascade function
Byte number Meaning PIQ
2 High byte
3 Low byte
4 High byte
5 Low byte
New setpoints can be specified at any time via the relevant PIQ area of the counter. However, the
setpoint is only transferred with the rising edge of RSC or when the counter passes zero.
Note
If the counter program detects a rising edge at the RSC input of the relevant
channel, a setpoint must be specified otherwise the counter will enter a zero loop
(start value "0", end value "0").
The assigned output will never be set.
When specifying a setpoint, enter the value in KH format in the relevant output words in the PIQ.
EWA 4NEB 812 6131-02
Meaning PII
Setpoint
High word
Setpoint
Low word
The Counter Functions
High byte Counter value
Low byte High word
High byte Counter value
Low byte Low word
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