User`s manual

CYDAS UDR Library User’s Guide Analog Input Boards - UCDAS 1602HRS
85
Event notification
Even notification functions and methods supported
UDR:
cbEnableEvent(), cbDisableEvent()
UDR for .NET:
EnableEvent(), DisableEvent()
Event types:
ON_SCAN_ERROR, ON_DATA_AVAILABLE, ON_END_OF_AI_SCAN
Hardware considerations
Acquisition rate
Since the maximum data acquisition rate depends on the system connected to the UCDAS 1602HRS, it is
possible to "lose" data points when scanning at higher rates. The CYDAS UDR Library cannot always detect
this data loss. Maximum rates may be lower in Windows operating systems that predate Windows XP. Most
systems can sustain rates of 80 kS/s aggregate. If you need to sample at higher rates than this, consider using
the
BURSTIO option explained later in this topic.
EXTCLOCK
You can set the SYNC pin as a pacer input or a pacer output from InstaCal. By default, this pin is set for pacer
input. If set for output, using the
cbAInScan()/AInScan() option EXTCLOCK results in a BADOPTION error.
BURSTIO
Allows higher sampling rates up to the size of the FIFO. The UCDAS 1602HRS FIFO holds 32,768 samples.
Data is collected into the USB device's local FIFO. Data transfers to the PC don't occur until the scan
completes. For
BACKGROUND scans, the Count and Index returned by cbGetStatus() and GetStatus() remain
0, and STATUS=RUNNING until the scan finishes. The
Count and Index are not updated until the scan is
completed. When the scan is complete and the data is retrieved,
cbGetStatus() and GetStatus() are updated
to the current
Count and Index, and STATUS=IDLE.
BURSTIO is required for aggregate Rate settings above 100 kHz, but Count is limited to sample counts up to
the size of the FIFO (32,768 samples).
Count settings must be an integer multiple of the number of channels
in the scan (see
Count above).
Continuous scans
When running
cbAInScan()/AInScan() with the CONTINUOUS option, you should consider the packet size and
the number of channels being scanned. In order to keep the data aligned properly in the array, make the total
number of samples an integer multiple of the packet size and the number of channels.
When running
cbAInScan()/AInScan() with the CONTINUOUS option, you must set the count to an integer
multiple of the packet size (62) and the number of channels in the scan.
Miscellaneous functions and methods supported
UDR:
cbFlashLED()
UDR for .NET:
FlashLED()
Causes the USB LED on a CyberResearch USB module to blink.
When you have several modules connected to the computer, use these functions to identify a particular
module by making its LED blink.