User`s guide

Universal Library User's Guide Analog Input Boards - USB-1616FS
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Counter I/O argument values
CounterNum: 1
Count 2
32
-1 when reading the counter.
0 when loading the counter.
cbCLoad() and cbCLoad32() / CLoad() and CLoad32()are only used to reset the
counter for this board to 0. No other values are valid.
The ―Basic signed integers‖ guidelines on page 140 apply when using cbCIn() or CIn() for values greater
than 32767, and when using cbCIn32() or CIn32() for values greater than 2147483647.
Event notification
Even notification functions and methods supported
UL: cbEnableEvent(), cbDisableEvent()
UL 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 USB-1616FS, it is possible
to "lose" data points when scanning at higher rates. The Universal 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 USB-1616FS 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.