nRF51 and nRF52 Firmware update with another MCU over UART

[Mehdi]

Hi,

I'm working on two projects, in the first one, nRF52832 (softdevice S132 V6.1.0)  is used as a slave component communicated with STM32L4+ over UART and the second one,  nRF51422 (softdevice S130 V2.0.1) is used as a slave component too and communicated with STM32L4 over UART.  

I'm asked to provide a solution to update nRF52 and nRF51 firmware by the STM32 through UART.

Do you have any suggestions for that? 

Best Regards,

Mehdi.

[Jørgen Holmefjord]

Hi,

We do not have any solutions for STM32, but we have som unofficial DFU master examples implemented in C. You can find it in Appendix 6 in this blog post.

I suppose it should be possible for you to port this example code to the STM32 devices.

Best regards,
Jørgen

[Jørgen Holmefjord]

Unfortunately, I'm not aware of any secure serial DFU bootloader for nRF51. Secure DFU was introduced in SDK 12.0.0, but only with BLE bootloader. Serial DFU bootloader was added to SDK 13.0.0, but nRF51 support was dropped from the SDK after SDK 12.3.0.

I checked with one of my colleagues, and he did not think there were major changes to the bootloader architecture in SDK 13, so the best option would be to port the secure BLE DFU bootloader in SDK 12.3.0 to serial transport. You can have a look at the serial bootloader in SDK 13.0.0 and try to imitate the code and port it back to SDK 12.3.0 BLE project for nRF51.