Analog Output - Omega OMB-DAQBOARD-3000 Series User Manual

Variable pre-trigger with post trigger stop event. Unlike the previous pre-trigger modes, this
o
mode does not have to satisfy the pre-trigger number of readings before recognizing the trigger
event. Thus the number of pre-trigger readings acquired is variable and dependent on the time of
the trigger event relative to the start. In this mode, data continues to be acquired until the stop
trigger event is detected. Driver support only.
Variable pre-trigger with infinite post trigger. This is similar to the mode described above, except
o
that the acquisition is terminated upon receipt of a command from the program to halt the
acquisition. Driver support only.
Calibration
Every range of a DaqBoard/3000 Series device is calibrated at the factory using a digital NIST traceable
calibration method. This method works by storing a correction factor for each range on the unit at the time
of calibration. The user can adjust the calibration of the board while it is installed in the acquisition system.
This does not destroy the factory calibration supplied with the board. This is accomplished by having 3
distinct calibration tables in the DaqBoard/3000 series on-board EPROM, one which contains the factory
cal, and two which are available for user calibration.
The user can select any of the three cal tables provided [factory, user or self-cal tables] by API call or from
within factory-included software, DaqCal.
The user-friendly DaqCal application supports two calibration modes: Self-Cal and User-Cal.
o Self-cal can be performed automatically in minutes with included software and without the use of
external hardware or instruments. Self-cal derives its tracebility through an on-board reference
which has a stability of 0.005% per year.
o User-cal is for users that require traceability to international standards such as NIST. A 6-1/2
digital multimeter is required and user calibration software is included with step-by-step
instructions for full calibration.
Note that a 2-year calibration period is recommended for DaqBoard/3000 Series boards.

Analog Output

DaqBoard/3000 and /3001 Only
DaqBoard/3000 has two 16-bit, 1 MHz analog output channels. DaqBoard/3001 has four such channels.
The channels have an output range of -10V to +10V. Through the use of Bus Mastering DMA, each D/A
output can continuously output a waveform at up to 1 MHz. This can be read from PC RAM or from a file
on the hard disk. In addition, a program can asynchronously output a value to any of the D/As for non-
waveform applications, presuming that the D/A is not already being used in the waveform output mode.
When used to generate waveforms, the D/As can be clocked in several different modes. Each D/A can be
separately selected to be clocked from one of the following sources.
o Asynchronous Internal Clock. The on-board programmable clock can generate updates ranging
from 1.5 Hz to 19 hours, independent of any acquisition rate.
o Synchronous Internal Clock. The rate of analog output update can be synchronized to the
acquisition rate derived from 1 MHz to once every 19 hours.
Asynchronous External Clock. A user-supplied external input clock can be used to pace the
o
D/A, entirely independent of analog inputs.
Synchronous External Clock. A user-supplied external input clock can pace both the D/A and
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the analog input.
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DaqBoard/3000 Series User's Manual