I am working with the HL7812 module and facing issues enabling and using GNSS. Despite following the standard AT command sequence, GNSS does not provide a fix and several GNSS-related commands return errors.
Below are the complete module details and command logs for your reference.
Module Information (ATI9):
HL7812.5.4.12.2-23.01.0.FreeRTOS.rc2
HL78xx.5.4.12.2.RK_03_02_00_22_24731_001.20230330
Build Date: 2023/03/30 08:42:08
IMEI-SV: 3511444414172812
Legato RTOS: 23.01.0.FreeRTOS.rc2
UBOOT: 01.03
Apps: RKAPP_03_02_00_22_24651_001
MAC: ALT1250_03_02_00_22_24731_2G
PHY: 12.50.314023
PMP: 315260
AISE: ISE2APP_00_00_00_09
SBUB: 1
SBFW: 1
RBUB: 0
RBFW: 0
MCU-Disable: 1
GNSS Test Logs:
AT+CFUN?
+CFUN: 1
OK
AT+GNSSSTART=1
OK
+GNSSEV: 0,1
+GNSSEV: 1,0
AT+GNSSSTART?
+GNSSSTART: 0
OK
AT+GNSSNMEA?
+CME ERROR: 60
AT+GNSSLOC?
+GNSSLOC:
FIX NOT AVAILABLE
OK
Additional Test with CFUN Toggle:
AT+CFUN=4
OK
AT+GNSSSTART=1
OK
+GNSSEV: 1,1
AT+CFUN=1
OK
AT+GNSSNMEA=1,1,0,0x49
+CME ERROR: 3
AT+GNSSLOC?
+GNSSLOC:
FIX NOT AVAILABLE
OK
Sleep Configuration:
AT+KSLEEP?
+KSLEEP: 2
OK
AT+KSLEEP=0
+CME ERROR: 3
Issues Observed:
AT+GNSSSTART=1does not remain enabled (GNSSSTART?returns0)- GNSS NMEA and configuration commands return CME ERROR 3 / 60
- GNSS never reports a valid fix (FIX NOT AVAILABLE)
- Unable to modify KSLEEP settings
- GNSS events indicate inconsistent states (+GNSSEV: 1,0 / 1,1)
Questions:
- Does firmware HL7812.5.4.12.2-23.01.0.FreeRTOS.rc2 support GNSS fully?
- What is the root cause/source of GNSS automatically disabling (GNSSSTART` returning 0)?
- Are CME ERROR 3 and 60 expected for GNSS commands under this firmware?
- Does KSLEEP = 2 or MCU-Disable = 1 prevent GNSS operation?
- Is there a known limitation, missing configuration, or firmware bug in HL7812.5.4.12.2-23.01.0.FreeRTOS.rc2 affecting GNSS?
- What is the correct sequence to reliably enable GNSS and obtain a fix on this platform?
