Hello
I would like to enable Ultra low power mode (ULP) on ag3335 GNSS chip on SenseCap T1000.
To do that according to the spec the “fitness” mode must be enabled. But I cannot enable it - the PAIR command ACK returns 4 (parameter error) and the PAIR “get” command returns value 0. The spec says that fitness mode (1) is the default but on the ag3335 firmware it is always 0 (generic) .
The ag3335 reports firmware version AG3335M_V2.6.0.AG3335_20221230 on my T-1000
The commands I used
$PAIR080,1*2F to enable fitness mode and
$PAIR081*33 to check the current value`
Another issue
The Sensecap ag3335 implementation calls a function gnss_scan_lock_sleep() to presumably prevent the chip from going to sleep after it toggles the chip reset line.
It uses PAIR382,1 command to do that . If scan_lock_sleep() is not called all PAIR commands sent to the chip fail (time out)
The command is not documented in the LOCOSYS spec but in other specs (Reyax, Quectel) it is described as “lock system sleep”
What does it do exactly and why no commands work if it’s not called?
The T-1000 implementation does not check what the part returns it just sends PAIR382 repeatedly in gnss_scan_lock_sleep and gnss_scan_unlock_sleep Any help or pointers would be much appreciated
Thank you
Andy
PJ 