BSP driven buttons don't work with a bootloader

[Alev]

Situation

1. I have an app, that use a BSP to detect pressing of the buttons. It works.

2. I have a bootloader. It also works.

Problem

When I flash bootloader AND app simultaneously, BSP cannot handle button pressing. No errors during init - just bsp_button_event_handler() never fire.

Environment

• SD 120 v.2.0
• NDK 8.0.0
• board PCA10001
• compiler GCC 4.9 2014q4
• I use a Hung Bui (@hungbui) proposed bootloader (see here), and memory values are as in answer here
• my app is based on the ble_app_multilink_central example from NDK8

Note

Doesn't matter if I flash bootloader then app or vice versa. Also, I try to flash bootlader and then load app with bootloader DFU. The result is the same - app is flashed, started, but buttons do not work.

Thank you.

[Alev]

I've just found, that GPIOTE_IRQHandler() don't fire when bootloader is flashed on.I can't imagine how an IRQ handler not fired? IRQ is a hardware option, isn't it?

Somebody knows where I can start to dig?

@hungbui, maybe it's deal with bootloader memory mapping/IRQ vector table remapping or so on?

[RK]

That's pretty curious.

Are you correctly finishing the bootloader process with bootloader_app_start(). That fixes up the softdevice handler table to point to the start of your code. Is your code in the right place and is CODE_REGION_1_START evaluating to something sensible (see bootloader.c).

It should be that your app code, when executed, re-sets up all the GPIOTE from scratch, including enabling the event, enabling the interrupt etc, if it didn't then it seems it wouldn't work standalone, however I'd break into the code whilst running and check all those things, is the PORT event enabled, is the IRQ enabled. The bootloader does disable all IRQs as the last thing before running user code, the startup code should re-enable them all, but it's worth checking.

You could also trace the IRQ handler, it's not that hard. It starts at 0x012a, it should load 0x1000 from 0x20000000, add 0x58 to it and branch to what's at that address, which should be 0x21e4. That in turn should load your vector table start from 0x20000004, add 0x58 to that and branch to your IRQ handler. Just putting a hardware breakpoint at 0x012a you should be able to see where it goes. If it doesn't even get hit, then the IRQ is somehow disabled.

[Hung Bui]

@Alev: I tried to reproduce the issue but was not able. I added bsp button into ble_app_multilink_central to toggle an LED when there is a button pressed. But there was no difference if the bootloader exist or not.

The bootloader I provided doesn't use GPIOTE Port event. It configures one button as input. As suggested by RK, have you made sure you reconfigured the button correctly in your application ?

You mentioned "When I flash bootloader AND app simultaneously", how did you do that, did you flash the application firmware via OTA DFU ?

I'm using KEIL to compile but I don't think it could make a difference.

[Alev]

Hello, thank you for your answer.

1. Yes bootloader is finished with: bootloader_app_start(DFU_BANK_0_REGION_START). Where DFU_BANK_0_REGION_START == CODE_REGION_1_START == SOFTDEVICE_INFORMATION->softdevice_size (it's info from dfu_types.h). My code starts, so I think it's in the right place. Maybe IRQ Vector table not in the right place, how can I check where linker places IRQ vector table?

2. Yes, you are right, as far as the app code works standalone - all IRQs should be set up correctly.

3. I use a gcc compiler for app, not Keil so I cannot debug. Alev

[Alev]

I've just obtained a positive result - bootloader works, and BSP also. Don't sure what was the problem - I just started from the @hungbui original example and modified it again (for my purposes). And it becomes work! Try it both from Windows and Android -app updated correctly. Thank you for your help.

One thing, that I should note is: when use a bootloader, direct flashing an application with programmer becomes not useful. This is because bootloader starts in any case - if I hold the bootloader button or not (probably bootloader thinks, that it's no application in the device). So, I can correctly update app only with bootloader DFU, but not with JTAG.