Unable to create bootloader for nRF52832

[buchnich]

Hello,

I am creating a wearable PCB with the Raytac MDBT4Q-P BLE module, which uses the nRF52832. I need this device to have OTA firmware capability, but I'm finding it nearly impossible to create a simple bootloader. I'm following this guide for creating the bootloader. Unfortunately, I've been having all sorts of issues trying to set this up on Mac, Windows, or Linux operating systems. Before I do a deep dive into troubleshooting my issues, I need to ask; is there just a standard bootloader .hex file that I can download somewhere and flash to the board? The process for creating a simple bootloader is extremely convoluted and requires that multiple 3rd-party tools work perfectly.

Thank you,

Nick 

[bjorn-spockeli]

Hi Nicholas, 

we have pre-compiled binaries for many of our examples in the nRF5 SDK. 

You can find the pre-compiled debug version of the bootloader for the nRF52832 DK( PCA10040) in <SDK folder> \examples\dfu\secure_bootloader\pca10040_s132_ble_debug\hex. Note this is compiled for the PCA10040 board, but it should work on custom boards as well, but the LED and button pins might not be correct. However, you should be able to see the Raytac module advertise as DfuTarg if it works. 

I recommend using the latest SDK, i.e. SDK v16.0.0. 

Best regards

Bjørn

[buchnich]

Bjorn,

I wasn't using the _debug folder, which is why I couldn't find the hex file. I have a custom board, so I will test it out later to see if everything still works. I'll verify your response as the answer if that goes well.

Thanks!

Nick

[bjorn-spockeli]

Ok, let me know if you run into any issues.

Best regards

Bjørn

[buchnich]

Bjorn,

I ran into an issue. I've seen this happen before when I've tried other examples, but after I flash the bootloader, I can't successfully flash the buttonless dfu example application. I know that the erase is the solution because I can see the log outputs in RTT viewer if I try to flash directly after the erase.

Any ideas?

[buchnich]

Do I need to change the BOOTLOADER_ADDRESS value in the nrf_dfu_svci.c file to 0x00078000?

[bjorn-spockeli]

No, the bootloader will write its start address to the MBR on boot and then following code line 

#define BOOTLOADER_ADDRESS      ((*(uint32_t *)MBR_BOOTLOADER_ADDR) == 0xFFFFFFFF ? *MBR_UICR_BOOTLOADER_ADDR : *(uint32_t *)MBR_BOOTLOADER_ADDR) /**< The currently configured start address of the bootloader. If 0xFFFFFFFF, no bootloader start address is configured. */

will retrieve the bootloader address by de-referencing the pointer to the memory address where the bootloader address is stored. 

Best regards

Bjørn