Setup of Demo System
5.3
Using the PC Application for Advanced Custom Control of the RF430FRL152HEVM
This section describes how to set up the RF430FRL152HEVM for a custom sampling process. The
example used here describes how to perform sampling of three sensors (reference, thermistor, and light
sensor) with four passes at a rate of one sample per second. Various ADC configurations are made using
the "Sensor Config." tab. This is a simple demonstration, and you can create more complex sampling
processes and control as needed.
1. Follow the steps in
to start the PC application and connect to the TRF7970AEVM.
2. In the "Setup" tab, make sure that "Without Sensor Hub BoosterPack" and "RF430FRL152HEVM" are
selected.
3. On the "Sensor Config." tab, for the reference and thermistor group boxes (near the top of the tab),
make the following settings: gain of 2, filter type of CIC filter, oversampling of 256. When gain of 2 is
used, the thermistor and reference input voltage does not use most of the analog voltage range. The
CIC filter allows for shorter conversion times (using 256 oversampling).
4. For the light sensor configuration, select gain of 1, CIC filter, and oversampling of 256.
5. Also on the same group boxes, select "Use Virtual Ground". Virtual ground allows the ADC module
and inputs to be raised above ground voltage by several hundred mV. Raising the ground allows the
ADC to more accurately measure voltages near ground. This setting must be chosen, because the
RF430FRL152HEVM was designed with virtual ground powering the thermistor and light sensors (the
SVSS pin is the virtual ground).
6.
shows the "Sensor Config." tab with these settings.
Figure 16. Custom Sensor Configuration Tab
7. Click the "Write only this tab" button on the bottom of the tab.
8. Go to the "Gen. Device Config" tab, and select the "Reference/ADC1", "Thermistor/ADC2", "Using
Thermistor", and "Light Sensor" options in the "Sensor Control Register" group box. These settings
determine which sensors are selected to be sampled.
9. Set "Number of Passes Register" to 4. This causes four sampling passes. A pass is sampling each of
the selected sensors in the "Sensor Control Register" once, in the order that they are selected.
10. Set "Frequency Register" to the "Every Second" option. This setting causes the selected delay to
occur between sampling processes.
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SLAU607 – December 2014
RF430FRL152HEVM User's Guide
Copyright © 2014, Texas Instruments Incorporated