Measurement Computing Data Acquisition Systems rev.10.4 - Manual (Page 70)

daqAdcRdN
Also See: daqAdcSetFreq, daqAdcSetMux,
daqAdcSetClockSource, daqAdcSetTrig,
daqSetTimeout
Format
daqAdcRdN(handle, chan, buf, scanCount, triggerSource, rising, level,
freq, gain, flags)
Purpose
daqAdcRdN takes multiple scans from a single acquisition channel.
Parameter Summary
Parameter Type Description
handle DaqHandleT Handle to the device from which the ADC channel
samples will be acquired
chan DWORD A single channel number
buf PWORD Array to which the acquisition scans will be returned
scanCount DWORD Number of scans to be taken
triggerSource DaqAdcTriggerSource The trigger source
rising BOOL
Boolean flag to indicate whether the edge for the
trigger source is rising or falling
level WORD The trigger level, if an analog trigger is specified
freq FLOAT The sampling frequency in Hz
gain DaqAdcGain The channel’s gain setting
flags DWORD
Channel configuration flags in the form of a bit mask
Parameter Values
handle: obtained form the daqOpen function
chan: must be a valid channel number for the device
buf: must be a valid pointer to memory whose size is at least equal to [scanCount * (the sample size,
normally 2 bytes)]
scanCount: valid values range from 1 to 4,294,967,295 scans; however, memory limitations apply.
triggerSource: see table below
rising: valid values are either true (
≠ 0) or false ( = 0)
level: valid values range from 0 to 65,535, representing the trigger level in raw, unsigned A/D counts
freq: see the daqAdcSetRate function for details.
gain: see ADC Gain Definition table for gain definitions
flags: see ADC Flag Definition table for flag configurations
Parameter Type Definitions
triggerSource-(DaqAdcTriggerSource)
Definition Description
DatsImmediate Begins taking post trigger scans immediately upon daqAdcArm function
DatsAdcClock Begins taking post trigger scans upon detection of next pacer clock pulse
DatsGatedAdcClock Begins taking post trigger scans upon detection of next gated pacer clock pulse
DatsExternalTTL Begins taking post trigger scans on the selectable edge of an external TTL signal on pin
25 of P1
DatsHardwareAnalog Begins taking post trigger scans upon a selectable criteria of the input signal (above
level, below level, rising edge, etc.)
4.2-14 Daq API Command Reference 988594 Programmer’s Manual