Can't get bootloader to log

[Lee Daniel Crocker]

Using SDK 12.2, I have compiled the secure bootloader successfully, tweaking the sdk_config and Makefile to use RTT for logging and turning on logging, and using the "_debug" linker script to place it at 0x75000. I used nrfutil to make a bootconfig.hex. I installed the bootloader, config, softdevice, and my app. Using JLinkExe, I can see all of them: SD at 0x0, my app at 0x1f000, bootloader at 0x75000 and config at 0x7f000.

When I boot the pca10040, LED3 comes on and stays on, but nothing is seen on the RTT console, I can't see the device advertising, and it appears hung. If I hold down button 4 while booting, LEDs 1 and 3 stay on, but still appears hung. Nothing ever shows on the RTT console.

It's hard to debug this if I can't see what's happening. Is there some reason the bootloader can't use RTT logging? Am I missing a step (for example, how does it know to look at 0x75000 instead of 0x78000)?

[Lee Daniel Crocker]

Odd results now. To go back to basics I burned the pre-compiled secure_dfu_secure_dfu_ble_s132_pca10040_debug.hex from the SDK. I was able to upload the sample ZIP from a Nexus tablet and a Samsung tablet. But it failed trying from a Motorola phone and an iPad. So maybe it's the mobile app side that's my problem.