ADLINK USB-1210 - Manual (Page 35)

Operation & Calibration 25
USB-1210
Figure 3-4: Configuring Different Sampling Rates
Sampling Rate Control with External Conversion Strobe
Clock
The A/D conversion clock can be provided by external strobe
clock via CONV pin. The valid frequency of external clock is from
DC to 2 MHz and the minimum pulse width is 225ns.
Analog Input Triggering
The USB-1210 supports flexible trigger sources for analog input
functionality. The trigger source can originate with software com-
mand, external analog, or external digital signal in continuous ana-
log input mode. Users can configure the trigger source and trigger
mode by software.
3.1.3 Trigger Sources
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.
External Analog Triggering
The analog multiplexer can select one input channel as the analog
trigger source. That is, one of 4 input channels in differential mode
can be selected as the analog trigger source. An external analog
TIMEBASE
DATA
D1
Acquisition
In Progress
Trigger
Acquisition begins following this clock edge
D1
ScanIntrv = 1
D2 D3 D4 D5 D6 D7 D8 D9 D10
D2 D3 D4 D5 D6
D1 D2 D3 D4
ScanIntrv = 2
ScanIntrv = 3