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Reading GNSS RSSI on LR1120

Semtech Transceivers LR1110/LoRa Edge
#1

Hi,

I am trying to read the GNSS RSSI using an LR1120 module using the following code. I get not errors on the lr11xx_gnss_* calls but get no valid RSSI.

lr11xx_status_t status = lr11xx_gnss_read_firmware_version(NULL, &version);
printf("status:%d fw:%u almanac:%u\n", status, version.gnss_firmware, version.gnss_almanac);
status = lr11xx_gnss_set_scan_mode(NULL, LR11XX_GNSS_SCAN_MODE_3_SINGLE_SCAN_AND_5_FAST_SCANS);
printf("scan mode status:%d\n", status);
lr11xx_gnss_date_t date = 1693554337;
status = lr11xx_gnss_scan_autonomous(NULL, date, LR11XX_GNSS_OPTION_DEFAULT, 7, 20);
printf("scan autonomous status:%d\n", status);
for (size_t i = 0; i < 100; i++) {
    status = lr11xx_gnss_read_gnss_rssi_test(NULL, &rssi_gnss_dbm);
    printf("status:%d rssi:%d\n", status, rssi_gnss_dbm);
    delay_ms(1000);
}

This prints the following:

status:0 fw:7 almanac:2
scan mode status:0
scan autonomous status:0
status:0 rssi:-1
status:0 rssi:-1
...

I have tried both scan modes LR11XX_GNSS_SCAN_MODE_3_SINGLE_SCAN_AND_5_FAST_SCANS and LR11XX_GNSS_SCAN_MODE_0_SINGLE_SCAN_LEGACY
and lr11xx_gnss_scan_autonomous / lr11xx_gnss_scan_assisted with the same results.

Me being a complete newbie on the LR1120, anyone more seasoned who can see what I did wrong?

Regards,
Johan