Update firmware from external flash

[abosch]

Hi,

I have a custom board with nRF52832 and I'm using SDK 13.1 and softdevice s132 4.0.5. I have a GPRS module that I will use to receive the new firmware image and I will save it on a external flash. Once whole firmware image is downloaded and verified, I want to execute the bootloader and update the firmware. As I know, the steps to do this are:

* Download image to external flash and verify it

* Save image settings like CRC, length, etc. to external flash

* Copy the image and settings to the internal flash of nRF52

* Enter to bootloader and load the image saved in bank1 of internal flash.

When I do the update via DFU, I generate a zip packet that contains a *.bin (encrypted image) and a *.dat (is this the init packet?), are these the files that I have to send to the GPRS module? or have I to send the hex application file and image settings in clear?

When the update is via DFU, the new image is saved in Bank1, how I will know this address? Is this address accessible from the application to copy the image from the external to internal flash?

Which are the main functions I have to check in bootloader to copy de firmware of bank1 to bank0? Do you have any example code of it? The bootloader code is a little bit tricky, so any help will be appreciated.

Thanks in advance.

[Turbo J]

The nrf bootloader really wants to communicate with the update host, which seems difficult or unreliable in your case.

I suggest ditching the nrf bootloader and write your own. Nordicsemi software is nice for BTLE over-the-air updates without external flash, but has too much bloat in your case.

[Bjørn Kvaale]

I think this devzone case sums it up pretty well. Like Turbo J says, the Nordic OTA-DFU examples are written without using external flash. You may need to write your own code if you want to use external flash. Would it be a possibility to buy an nRF52832 with more flash? That way, you may not need to use external flash.