Texas Instrument SLOA233 application. Designed to read temperature data from the RF430-TMPSNS-EVM using the MSP-EXP430FR4133 launchpad and the DLP-7970ABP booster pack.
Source code can be downloaded here. A few changes have been made to make it work.
Fix compilation error caused by include casing.
Fix watchdog disable not working.
Enable UART host logging
Allow sending only RSSI by UART
Ensure that the IRQ jumper on the DLP-7970ABP booster pack is set to position 1 (default) as described in DLP-7970ABP Hardware Update Overview
The software has been modified to allow sending the RSSI to the host via UART. The datasheet of the transceiver says (page 69) the following:
RSSI measurement block is measuring the demodulated envelope signal (except in case of direct
command for RF amplitude measurement described later in direct commands section). The measuring
system is latching the peak value, so the RSSI level can be read after the end of receive packet. The
RSSI value is reset during next transmit action of the reader, so the new tag response level can be
measured. The RSSI levels calculated to the RF_IN1 and RF_IN2 are presented in Section 6.5.1.1 and
Section 6.5.1.2. The RSSI has 7 steps (3 bits) with 4-dB increment. The input level is the peak-to-peak
modulation level of RF signal measured on one side envelope (positive or negative).
The UART message looks like this:
RSSI: 05
RSSI: 05
RSSI: 05
RSSI: 05
RSSI: 05
RSSI: 05
RSSI: 05
RSSI: 06
RSSI: 07
RSSI: 07
RSSI: 07
RSSI: 07
RSSI: 07
RSSI: 05
RSSI: 05
RSSI: 05
RSSI: 05
RSSI: 04
For simplicity's sake, the RSSI value is sent at the same time the bar chart is refreshed on the LCD.
MSP430FR413x mixed-signal microcontrollers datasheet
MSP430FR4xx and MSP430FR2xx family user's guide
DLP-7970ABP Hardware Update Overview
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