EMX Board Bringup


We have incorporated the EMX module onto a base board that we have developed but I am currently unable to talk to the bootloader via the USB. We seem to have all of the JTAG, reset, and USB signals configured in the same fashion as the development board (which does work). Basically when I connect the USB port the PC does not see it at all. We are not user Ethernet. Could it be that the Ethernet is preventing the board from running? Is there some way the pins should be configured? Does anyone have any tricks to see if the processor on the board is in fact running (since it is a BGA there is no easy access to the pins)?

Thanks for any help anyone can provide in getting our board to power on.


When you power on and connect to use see the device being enumerated on the Windows Device manager ?

What are the Up (pin 7), down (pin 3) and select (pin 53) pins connected to ?


Thanks for your reply. We found out what the issue was. We had added a EMI/ESD protection IC on the D+/D- lines that seems to interfere with the USB detection (or we have it wired incorrectly - the EE on the project is out of the office today so I will have him look at it on his return). We have temporarily removed the part and the board now communicates with my PC over the USB port.

Thanks and I apologize for turning to the board too soon.


You need to pull down the mode pin to get it boot up in USB debugging mode.