Agilent Technologies InfiniiVision 5000 Series Programmer's Manual page 48

3
Getting Started
Ensure New Data is Collected
N O T E
When you change the oscilloscope configuration, the waveform buffers are cleared. Before
doing a measurement, send the :DIGitize command to the oscilloscope to ensure new data
has been collected.
When you send the :DIGitize command to the oscilloscope, the specified
channel signal is digitized with the current :ACQuire parameters. To obtain
waveform data, you must specify the :WAVeform parameters for the
SOURce channel, the FORMat type, and the number of POINts prior to
sending the :WAVeform:DATA? query.
Set :TIMebase:MODE to MAIN when using :DIGitize
N O T E
:TIMebase:MODE must be set to MAIN to perform a :DIGitize command or to perform any
:WAVeform subsystem query. A "Settings conflict" error message will be returned if these
commands are executed when MODE is set to ROLL, XY, or WINDow (zoomed). Sending the
*RST (reset) command will also set the time base mode to normal.
The number of data points comprising a waveform varies according to the
number requested in the :ACQuire subsystem. The :ACQuire subsystem
determines the number of data points, type of acquisition, and number of
averages used by the :DIGitize command. This allows you to specify exactly
what the digitized information contains.
The following program example shows a typical setup:
myScope.WriteString ":ACQuire:TYPE AVERage"
myScope.WriteString ":ACQuire:COMPlete 100"
myScope.WriteString ":ACQuire:COUNt 8"
myScope.WriteString ":DIGitize CHANnel1"
myScope.WriteString ":WAVeform:SOURce CHANnel1"
myScope.WriteString ":WAVeform:FORMat BYTE"
myScope.WriteString ":WAVeform:POINts 500"
myScope.WriteString ":WAVeform:DATA?"
This setup places the instrument into the averaged mode with eight
averages. This means that when the :DIGitize command is received, the
command will execute until the signal has been averaged at least eight
times.
After receiving the :WAVeform:DATA? query, the instrument will start
passing the waveform information.
Digitized waveforms are passed from the instrument to the controller by
sending a numerical representation of each digitized point. The format of
the numerical representation is controlled with the :WAVeform:FORMat
command and may be selected as BYTE, WORD, or ASCii.
48 Agilent InfiniiVision 5000 Series Oscilloscopes Programmer's Guide