Most common issue is power supply. When a board isn't designed to be flashed this way, voltage may leak to other components on the mainboard. Hence board-specific documentation is so important. Measuring voltage when trying to access the flash may give a clue.

Without documentation it's best not to apply voltage via the flash programmer (RPi in your case), in case you were trying this. Better is to use the board's regular power supply and making sure that it doesn't boot (i.e. stays in a soft-off / S5 state). And *not* connec- ting VCC to pin8. Again, measuring voltage at the flash chip.

That it's a WSON chip also doesn't make things easy. Did you solder something and can confirm connectivity? or how do you connect to the flash chip?

I got a WSON-8 8x6 probe. It has to be held down on the chip by hand so there is no way for me to measure voltage at the same time. I have tried the following configurations with my RPi: No pw supply connected to mainboard - pins 1-8 connected between RPi and chip. Results= RPi reboots as soon as probe is placed on the chip No pw supply connected to mainboard - all pins connected except pins 3 and 7. Result= chip not detected Pw supply connected to mb, S5 soft off - all pins connected except pin 8. Result= chip not detected To enter S5 I power on the chromebox, then power off using power button. I tried reading voltage at the BIOS chip while power is connected to MB in S5 soft off. I don't get any voltage reading while connected to pin 4 GND and any other pin, or pin 8 VCC while connected to any other pin. This doesn't make sense to me. I think the chip should have power when the MB has power. I am just using a regular multimeter with nothing soldered to the board, just reading with needle tip probes.