WP77XX Firmware Update Needs Pin 47 (TP1) Pulled Low Every Time For Programming?

Hello,

I am using the WP7702 on a custom designed PCB that is based on the MangOH Green reference design. For all intents and purposes, the custom board is supposed to be equivalent, minus the LAN chip, audio components, and Arduino/IOT hookups.

When I try to flash my board with the 9999999_9907787_SWI9X06Y_02.16.06.00_00_ATT_001.026_001.spk file downloaded from the Sierra Wireless website, I always need to have the boot pin (Pin 47) manually pulled low. If I don’t, the programming process hangs and does not complete. On the Green MangOH board, I never have to do this. Both my board and the Green MangOH are confirmed to be using the WP7702 modem. I have tried programming using the swiflash utility and in Developer Studio with similar results. Has anyone else seen this? Any other information that would be helpful in sorting out this issue?

Thanks in advance,
Mike

What’s the USB status when the process hangs? Disconnected? or ?

Hi All,

Just wanted to let anyone that runs into this problem know how this was solved.

Turns out, I had the JTAG resistors populated on my PCB but was not using them for anything. Removing these allowed the board to program normally. Hope this helps!