Counter Clock Source; Counter Internal Clock; Counter Gate Source - Advantech UNO-3072 User Manual

2.7.5 Counter Clock Source

There are two clock sources available for the user counters by setting
counter clock control bits - CTR0CLKSet and CTR1CLKSet.
Table 2.12: Counter Clock Source Control Bit
CTR0CLKSet
CTR1CLKSet

2.7.6 Counter Internal Clock

There are four frequency options to choose according to applications, and
it's set by internal clock control bits - S0 and S1.
Table 2.13: Counter Internal Clock Control Bit
S1
0
0
1
1

2.7.7 Counter Gate Source

The gate sources you select determine what kind of gate input signal to
enable your counter/timer when receiving clock input. There are two gate
sources available for the user counters by setting gate source control bits -
CTR0GateSet and CTR1GateSet.
Table 2.14: Counter Gate Source Control Bit
CTR0GateSet
CTR1GateSet
0 Internal clock (default)
1 External clock from digital input 1 (DI1) channel
0 Internal clock (default)
1 External clock from digital input 3 (DI3) channel
S0
0
1
0
1
0 Gate source from "CTR0Gate" control bit (Default)
1 Gate source from digital input 0 (DI0) channel
0 Gate source from "CTR1Gate" control bit (Default)
1 Gate source from digital input 2 (DI2) channel
Time base
100 KHz (default)
10 KHz
1 KHz
100 Hz
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