11
View
Provides an optional control to display any combination of the available axes (only in case of
ADcmXL3021).
Note about plot setting
•
Right Click any plot to display the scaling controls.
•
Scaled coordinates of the cursor are displayed at the bottom of each plot.
•
Demonstrations in this mode may seem unresponsive due to the large data set.
Comm
Provides access to view state of the USB interface connection state.
Help
Provides general information regarding the software revision and provide some basic operating
information. For more information about the operation of the ADcmXL module please refer to the
datasheet.
About
Provides a window with software revision.
Mode Selection (AFFT, MFFT, MTC and RT)
Automatic FFT (AFFT) Capture Mode
In automatic FFT mode the ADCMXL will continuously self-trigger data capture with a period
determined by the value set in the REC_PRD register. The re-trigger time (REC_PRD) must be
greater than the data capture time which is determined by the values in the FFT_AVG and
AVG_CNT registers.
Note: if the REC_PRD time is smaller than the acquisition time of the FFT the ADCMXL Evaluation
Software will generate an error, will give the estimated capture time and terminate sample capture.
Automatic FFT Capture Example
The following steps configure the ADCMXL for an automatic FFT mode repetition rate of 2
seconds
1. Select “Automatic FFT” from the Mode Selection pull down menu.
2. Open Register Access Window.
3. On the left panel, use the slider to find the Register called AVG_CNT. Use the pointer to
select this register after which the register name will appear in the top center of the
Register access window. Enter “02” in the New Hex Value entry and push the “Write”
button (this will set the time average to 2
2
). Note: this will set the AVG_CNT for SR0, which
is the default Sample Rate configuration.
4. On the left panel, use the slider to find the Register called FFT_AVG1. Use the pointer to
select this register after which the register name will appear in the top center of the
Register access window. Enter “102” in the New Hex Value entry and push the “Write”
button. (This configures SR0 FFT averaging to 2, and leaves SR1 rate at the default value.
For further information regarding the sample rate configuration please refer to the
datasheet of the product.) This selection along with the above AVG_CNT setting, sets the
device for a capture duration of 1.8 seconds.
