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Counter processing and maximum counting speed
The A2C uses up-timing counters which increase their present values on the
leading edge of an input signal.
Counters are used by incorporating in the main routine programs or sub
Counter present value and contact status update
Counter coil Is switched on and off by the OUT C[
counter present value is updated on the leading edge of the coil signal
after the END (FEND) instruction is executed. The counter contacts
close after the counter has counted out.
The counters retain their
present value and contact status even if the counter coil is switched off.
When the counter is reset by the RST C[
instruction, the present value
is reset to 0 and the counter contacts open.
Counter present value updated
Counter contact status updated
Fig. 4.3 Counter Processing
The maximum counting speed of the counter depends on the scan time. Counting Is only
the input condition is on for more than one scan time. For further details, see the
ACPU Programming Manual.
Maximum counting speed Cmax
Duty is the ratio of the input signal's on time to off time as a percentage.
Count input signal
Tf+T2X 100 (%)
n = Tf+T2x 100 (%)
Program scan time (sec)