ADLINK Technology USB-1901, User Manual

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Operation 41
USB-1900 Series
Example:
1. Set:
X SI2_counter = 320
X
SI_counter = 1280
X PSC_counter = 3
X NumChan_counter = 4
X timebase = Internal clock source
X Channel entries in the Channel Gain Queue: ch1, ch2, ch0,
ch2
2. Then:
X Acquisition sequence of channels: 1, 2, 0, 2, 1, 2, 0, 2, 1,
2,0, 2
X Sampling Interval = 320/80M s = four us
X
Scan Interval = 1280/80M s = 16 us
X Equivalent sampling rate of ch0, ch1: 62.5 kHz
X Equivalent sampling rate of ch2: 125 kHz
4.2.5 Analog Input Triggering
The USB-1900 Series supports flexible trigger sources for ana-
log input functionality. The trigger source can originate with
software command, external analog, or external digital signal in
continuous analog input mode. Users can configure the trigger
source and trigger mode by software.
4.3 Trigger Sources
4.3.1 Software Triggering
This trigger mode requires no external trigger source. The trigger
asserts immediately following execution of the specified function
calls to begin the operation.