PC Oscilloscope User Guide PicoScope 2104, PicoScope 2105

Technical reference
19
Copyright 2006 Pico Technology Limited. All rights reserved. PS2100044-1.0
3.3.14
ps2000_set_trigger
short ps2000_set_trigger ( short handle,
short source,
short threshold,
short direction,
short delay,
short auto_trigger_ms )
This function is used to enable or disable triggering and its parameters. Triggering is
not available in streaming mode.
Arguments
handle
, the handle to the required device.
source
, specifies where to look for a trigger.
Use
PS2000_CHANNEL_A
(
0
) or
PS2000_NONE
(
5
).
threshold
, the threshold for the trigger event. This is scaled in 16-bit
ADC counts at the currently selected range.
direction
. Specifies the edge on which to trigger. Use
PS2000_RISING
(
0
) or
PS2000_FALLING
(
1
).
delay
, specifies the delay, as a percentage of the requested number of
samples, between the trigger event and the start of the block. It
should be in the range -100% to +100%. Thus, 0% means that the
the trigger event is at the first data value in the block, and -50%
means that it is in the middle of the block.
auto_trigger_ms
, the delay in milliseconds after which the unit will
collect samples if no trigger event occurs. If this is set to zero, the unit
will wait for a trigger indefinitely.
Returns
0
if one of the parameters is out of range, otherwise
1
.
3.3.15
ps2000_stop
void ps2000_stop ( short handle )
Call this function to stop the unit sampling data. If this function is called before a
trigger event occurs, the unit may not contain valid data.
Arguments
handle
, the handle to the required device.
Returns
0
if an invalid handle is passed, otherwise
1
.