Advantech PCM-3780 manual Mode H Waveforms

D.9 Mode H Waveforms

Software-Triggered Delayed Pulse One-Shot with Hardware Gating

Mode H is identical to Mode G except that the gate input is used to qual- ify which source edges are to be counted. 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 G, the counter will be reloaded from the Hold register on the first TC and reloaded from the Load register and disarmed on the sec- ond TC. This mode allows the Gate to control the extension of both the initial output delay time and the pulse width.

SOURCE

WR

ARM

COMMAND

GATE

COUNT

X

L

L-1

L-2

K+1

K

K-1

2

1

0

H

H-1 H-2

N+1

VALUE

TC OUTPUT

TC TOGGLED

OUTPUT

SOURCE

WR

GATE

COUNT	N+1	N	N-1	2	1	0	L
VALUE

TC OUTPUT

TC TOGGLED

OUTPUT

Mode H

Waveforms

PCM-3780 User Manual 54