CompuScope SDK Manua.. - Egmont Instruments

slope_1 and slope_2 are the trigger slopes and can be either positive or negative. The constants
GAGE_POSITIVE and GAGE_NEGATIVE should be used.
The level_1 and level_2 parameters can be any value between 0 and 255 for 8-bit CompuScopes. The
values are scaled internally to match the trigger input range selected. The minimum input level is 0 while
the maximum trigger level is 255. The trigger level voltage can be calculated from the equation:
TRIGGER LEVEL VOLTAGE = [(level – 128)/128] * INPUT SENSITIVITY OF TRIGGER SOURCE
For instance, suppose the trigger source was channel A and channel A was set to the ±200 milliVolt input
range. If level_1 was set to 192, then the trigger level voltage is calculated as:
TRIGGER LEVEL VOLTAGE = [(192– 128)/128] * 200 mV = 100 mV
For CompuScopes with more than 8-bit resolution, the level_1 and level_2 parameters can be any value
between 0 and 4096. The values are scaled internally to match the trigger input range selected. The
minimum input level is 0 while the maximum trigger level is 4095. The trigger level voltage can be
calculated from the equation:
TRIGGER LEVEL VOLTAGE = [(level – 2048)/2048] * INPUT SENSITIVITY OF TRIGGER SOURCE
For instance, suppose the trigger source was external trigger and ext_gain was set to GAGE_PM_5_V. If
level_1 was set to -1024, then the trigger level voltage is calculated as:
TRIGGER LEVEL VOLTAGE = [(1024– 2048)/2048] * 5V = -2.5V
The depth parameter sets the trigger depth, which is the number of samples to be captured after the trigger
event. The minimum value varies for different CompuScope models and operating modes. For instance,
for the CS14100 in single record/single channel mode the minimum depth is 512 samples, while in
multiple record/dual channel mode the minimum depth is 256. See your CompuScope hardware manual
for the valid minimum settings.
Increments to the capture depth cannot be 1. There is a minimum depth increment for each different
CompuScope model and operating mode. For instance for the CS14100 in single record/single channel
mode, the depth may be increased from the minimum of 512 points in increments of 256 points. See your
CompuScope hardware manual for the valid increment settings.
Several defined constants are available to the application programmer in order to set the depth. These are
listed in gage_drv.h and in the CompuScope C/C++ SDK manual. For instance, the constant
GAGE_POST_4K can be used to set the depth to 4096 points. Direct numeric values can also be used to
specify the depth.
If the specified depth parameter does not conform to the minimum and increment requirements of the
CompuScope hardware, the driver will adjust the depth to an appropriate allowed value.
The trigger_from_bus parameter should always be set to TRUE (non-zero). For normal operation in a
Master/Slave Multi-Card CompuScope system, the trigger_to_bus parameter should be set to TRUE (nonzero)
for the Master CompuScope and to FALSE (zero) for the Slave CompuScope(s). With these settings,
the Master CompuScope will serve as the Master trigger source and will pass its trigger signal to all Slave
CompuScopes. Some CompuScope models support triggering from Slave CompuScopes. For these
models, the trigger_to_bus parameter may be set to 1 for the Slave CompuScope(s). With these settings,
a trigger event on any Slave CompuScope, with its own trigger settings, will cause the whole Master/Slave
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