Advantech PCM-3780 manual Mode K Waveforms, Variable Duty Cycle Rate Generator with Level Gating

D.12 Mode K Waveforms

Variable Duty Cycle Rate Generator with Level Gating

Mode K is identical to Mode J except that source edges are only counted when the Gate is active. The counter must be armed for counting to occur.

Once armed, the counter will count all source edges that occur while the gate is active and disregard those source edges that occur while the gate is inactive. This permits the gate to turn the count process on and off.

As with Mode J, the reload source used will alternate on each TC, starting with the Hold register on the first TC. After the gate modulate the duty cycle of the output waveform. It can affect both the high and low portions of the output waveform.

SOURCE

GATE

COUNT

2

1

0

H

H-1 H-2

K+1

K

K-1

2

1

0

L

L-1

L-2

N+1

VALUE

TC OUTPUT

TC TOGGLED

OUTPUT

SOURCE
GATE
COUNT	N+1	N	N-1	2	1	0	H	H-1 H-2
VALUE

TC OUTPUT

TC TOGGLED

OUTPUT

Mode K

Waveforms

57 AppendixD