Waveform Capture Commands

The CAPT command is used to launch or stop the Waveform Capture functionality. It is also used to retrieve the current status of Capture.

When launching the Capture, parameters to be provided are:
  • Channel: One of the available channels
  • Source:
    • 0 - CAPTURE_SRC_16KHz captures 16 kHz data [sQ1.30] before DSP filtering
    • 1 - CAPTURE_SRC_4KHz_FBW captures 4 kHz FBW data [sQ2.29] (Full Bandwidth = fundamental + harmonics)
    • 2 - CAPTURE_SRC_4KHz_NBW captures 4 kHz NBW data [sQ2.29] (Narrow Bandwidth = fundamental only)
    • 3 - CAPTURE_SRC_8KHz_FBW captures 8 kHz FBW data [sQ2.29] (Full Bandwidth = fundamental + harmonics)
  • Type:
    • 0 - CAPTURE_ONE_SHOT captures total CAPTURE_BUFF_SIZE of future data. Capture will stop after capture finishes or is disabled
    • 1 - CAPTURE_CONTINUOUS captures of waveform data in circular-buffer fashion. Capture will stop immediately after capture is disabled
  • Capture length

Examples:

;Enable Capture on Channel 1, source: 16 kHz data before DSP filtering,  type: One Shot, length: 256 samples 
CAPT 1 1 0 0 256
Launched Waveform capture
;Check Capture Status
CAPT
Waveform capture is COMPLETE
;Stop Capture
CAPT 0
Stop Waveform capture

The BUF command allows to access the metrology samples being captured and processed. The Capture has to be previously launched by means of the CAPT command.

If the command is sent without a parameter, the Demo Meter Application returns all the data in the buffer. If the command includes a parameter (for example, BUF[2]), only a 512 sample set is returned. The parameter indicates the index of the set of samples (BUF[0] returns samples 0 to 511, BUF[1] returns samples 512 to 1023, and so on).

;Read out the captured waveform data
BUF
Waveform Capture Data:
A4865843
6C875498
23843F36
96636D63
...
42367B13
32436C32