User manual

D.3 Mode C waveform

Hardware-Triggered Strobe

Mode C is identical to Mode A, except that counting will not begin until

a Gate edge is applied to the armed counter, the counter must be armed

before application of the triggering Gate edge; Gate edges applied to a

disarmed counter are disregarded.

The counter will start counting on the first source edge after the

triggering Gate edge and will continue counting until TC. At TC, the

counter will reload from the Load register and automatically disarm

itself. Counting will then remain inhibited until a new ARM command

and a new Gate edge are applied in that order.

Note that after application of a triggering Gate edge, The Gate input will

be disregarded for the remainder of the count cycle. This differs from

Mode B, where the Gate can be modulated throughout the count cycle to

stop and start the counter.

SOURCE

ARM

COMMAND

COUNT

VALUE

TC OUTPUT

TC TOGGLED

OUTPUT

GATE

L L-1 L-2 2 1 0 L

Mode C Waveforms