Are they resetting on power up? Reset button make them reset? Is the oscillator oscillating? What is the difference in power supply current between working and non working? Higher in non working might indicate short, solder bridge, too much flux. JTAG connection? Boot loaded programmed in?
On the PDF of the PocketBeagle-VDD power plane, only P1.14 and P2.23 appear to be connected, I could have missed the other connections. Again on the GND plane, only P1 and P2 connected. I guess the vias do not have thermals. Has the PCB delaminated? <http://www.surfacemountprocess.com/-pcb-delamination-during-reflow.html> And broken the vias or tracks? On Thursday, 16 July 2020 10:10:53 UTC+1, Wapeul wrote: > > We made the board with the open source of Pocket Beagle. > https://github.com/beagleboard/pocketbeagle > > We made a total of five. > Only one of them works, and four do not. > I don't know the cause. > All pin maps have the same voltage. > The voltage of EMU0 (CDN of SD card connector) is 3.3V for normal board > and 0V for abnormal board. > > > > How to solve it? > What do we need to check? > > Best regards > CH Cho > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/2fa82557-05c8-49bc-8167-1bd9f50cf121o%40googlegroups.com.
