|Data Acquisition Toolbox Release Notes|
Known Software and Documentation Problems
This section describes known problems associated with Keithley hardware.
For a list of bugs reported in the previous release that remain open, see Known Software and Documentation Problems.
Known problems associated with Keithley hardware are described below. If there is a known resolution, then it is described as well.
|Data missed event on output
||For high sample rates and large numbers of samples, these boards may drop samples on output. To avoid this problem, try increasing the default
|No output at maximum sampling rate
||When the sampling rate is set above 600 kHz, the output is corrupted.
|Cannot sample properly below 10 Hz
||For sample rates at or below approximately 10 Hz, the acquisition takes longer than expected. For example, a one second acquisition at 10 Hz takes approximately three seconds.
This is due to a limitation in the number of blocks that the hardware device can transfer at a time. To avoid this problem, use software clocking.
|Time out on output
||Software clocked devices
||Some software clocked devices may time out when outputting data. This is due to a limitation in the number of blocks that the hardware devices can transfer at a time.
|Queuing data while running
||If an analog output object is running and more data is queued, then no data is output. To avoid this problem, try increasing the default
|Digital triggers are not available
||Digital triggers are not available if supported in interrupt mode. This applies to both start and stop triggers. Digital triggers are available only if supported in DMA mode.
|Limited channel skew values
||These boards support only these specific channel skew values: 10 us, 20 us, 40 us.
|SS/H not supported for analog output
||PCMCIA boards, DDA-08, DDA-16
||The analog output subsystems for these boards have simultaneous sample and hold (SS/H) capabilities. However, the toolbox does not support this feature.
|Repeating triggers may result in dropped samples
|Analog input subsystem not available
|National Instruments Hardware||Data Acquisition Toolbox 2.1 Release Notes|