After some time I’ve noticed updates to this thread - one remark - there are populated pins for I2C1 of STM32 on F4 2-3S 20A AIO FC V1 board that could be used e.g. for compass - see attached photos. I’ts PB9 for SDA and PB8 for SCL.
Betaflight uses only one of these pins (SDA/PB8/B08) for PPM but it’s not documented on BetaFPV page.
Andy, did you solve the Altitude estimate issue described in Altitude estimate issue - #14 by _sobi ? I’ve bought new board, but I left Betaflight on it for now.
One more lesson learned that could save some time for someone - if you disable power for internal ELRS receiver as documented on F4 2-3S 20A AIO FC V1 – BETAFPV Hobby you will also cut-off power to pad of the boot button and it will be not possible to get board to DFU mode with this button (e.g. to flash Ardupilot instead of Betaflight and back). I had to get to DFU with wire connection of 3.3V to pad of that button as workaround.
And this is my current setup of Pavo20 Pro with working GPS and O3 unit. But you’re right that getting GPS lock takes longer than I’m used to.
