I had the same issue. Solved by flashing a new firmware via tftp and connecting the onboard spi-pins.
@jside Could you share some info about the pinout and connection settings?Did you use a standard serial cable or something like an Arduino TTL serial cable or what??
I used a cable similar to this one: https://lawicel-shop.se/elektronik/kommunikation/rs232/usb-to-ttl-33v-serial-cable-for-rpi/
But basically any 3.3V serial to usb cable would work.
Using mincom in linux to connect 115200 8N1
Pinout something similar to:
(Not my picture, borrowed on internet)
Login with super and sp-admin as password in the console
You need to setup a tftp server. I used my laptop with the same ip range as the AccessPoint, and had a tftp server running locally on it.
Then you can flash by:
fw set host <TFTP server IP address>fw set proto tftpfw set port 69fw set control <image file name>fw updatereboot
image file name is the firmware you want to flash onto the ap, which should be located on your tftp.
@jside Thanks very much, I will give this a shot tomorrow.