Trigger modes and appendant registers

External TTL trigger

 

 

TTL pulsewidth trigger for long LOW pulses

This mode is for detecting LOW pulses of an external TTL signal that are longer than a programmed pulsewidth. If the pulse is shorter than the programmed pulsewidth, no trigger will be de- tected. The board will trigger on the first pulse matching the trig- ger condition after starting the board. The next triggerevent will then be detected, if the actual recording/replay has finished and the board is armed and waiting for a trigger again.

Register

Value

Direction

Description

SPC_PULSEWIDTH

44000

r/w

Sets the pulsewidth in samples. Values from 2 to 255 are allowed.

SPC_TRIGGERMODE

40000

r/w

Sets the triggermode for the board.

 

TM_TTLLOW_LP

20011

Sets the trigger mode for external TTL trigger to detect LOW pulses that are longer than a programmed pulsewidth.

TTL pulsewidth trigger for short LOW pulses

This mode is for detecting LOW pulses of an external TTL signal that are shorter than a programmed pulsewidth. If the pulse is longer than the programmed pulsewidth, no trigger will be detect- ed. The board will trigger on the first pulse matching the trigger condition after starting the board. The next triggerevent will then be detected, if the actual recording/replay has finished and the board is armed and waiting for a trigger again.

Register

Value

Direction

Description

SPC_PULSEWIDTH

44000

r/w

Sets the pulsewidth in samples. Values from 2 to 255 are allowed.

SPC_TRIGGERMODE

40000

r/w

Sets the triggermode for the board.

 

TM_TTLLOW_SP

20012

Sets the trigger mode for external TTL trigger to detect LOW pulses that are shorter than a programmed pulsewidth.

SpcSetParam

(hDrv,

SPC_TRIGGERMODE,

TM_TTLHIGH_LP); //

Setting up external TTL

trigger to detect high pulses

SpcSetParam

(hDrv,

SPC_PULSEWIDTH ,

50

); //

that are longer than 50

samples.

 

 

 

 

 

 

 

(c) Spectrum GmbH

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Spectrum Brands MC.31XX manual TTL pulsewidth trigger for long LOW pulses, TTL pulsewidth trigger for short LOW pulses