For my production I use DFU mode to initially program the photon (without headers).
My pcb assembly currently have 17 defective units on 100 units that cant be detected when connected with usb cable in dfu mode (led is flashing yellow but usb is not detected).
I ordered over 500 photon and it’s the first time I have so much trouble. Photon were purchased directly from particle wholesale.
Any suggestions. I cant make test by myself right now because it’s in the pcb assembly hands.
I tried to contact particle support without answer for 2 days now.
I need a solution or answer quick. Thanks