Measurement Computing Data Acquisition Systems rev.10.4 - Manual (Page 81)

daqAdcSetDataFormat
Also See: daqAdcSetMux, daqAdcSetClockSource, daqAdcSetTrig, daqAdcRdN
Format
daqAdcSetDataFormat(handle, rawFormat, postProcFormat)
Purpose
daqAdcSetDataFormat sets the format for both the raw and post-acquisition data returned by the
acquisition transfer functions.
Parameter Summary
Parameter Type Description
handle DaqHandleT The handle to the device for which to set
the data format
rawFormat DaqAdcRawDataFormatT Specifies the raw data format
postProcFormat DaqAdcPostProcDataFormatT Parameter value specifying the data
formats available
Parameter Values
handle: obtained from the daqOpen function
rawFormat: see table below
postProcFormat: see table below
Parameter Type Definitions
rawFormat-(DaqAdcRawDataFormatT)
Definition Description
DardfNative Data format follows the native-data format of the device it originated from.
DardfPacked Raw acquisition values are compressed, using empty bits in native format (WaveBook/512 only)
postProcFormat-(DaqAdcPostProcFormatT)
Definition Description
DappdfRaw Post-acquisition data follows the rawFormat parameter --this is the default setting.
DappdfTenthsDegC Data format is in tenths of a degree Celsius
Returns
DerrNoError No error
Function Usage
Raw Data Formats
The rawFormat parameter indicates how the raw data format will be presented. Normally, the raw-data
format represents the data from the A/D converter. The default value for this parameter is DardfNative
where the raw-data format follows the native-data format of the A/D for the particular device. The parameter
can also be set to DardfPacked, which compresses raw A/D values in order to make full use of all unused
bits in any native format that leaves unused bits in the byte-aligned count value. For instance, a 12-bit raw
A/D value (which would normally be represented in a 16-bit word, 2-byte count value) will be compressed so
that 4 12-bit A/D raw counts can be represented in 3 16-bit word count values. Currently, only the
WaveBook/512 supports this packed format (used with the generic functions of the form
daqAdcTransfer
…).
Programmer’s Manual 908594 Daq API Command Reference 4.2-25