Update firmware over the air ( FOTA) for nRF52833 using UART from Module Sim

[John12]

Hi,
I'm developing an application using nRF52833 and Module Sim.
This project use BLE, PWM, libuarte, 3 app timers, saadc 
Now I want to add an feature that is update firmware over the air for nRF52833.
The firmware image will be taken from Module Sim (communicating with nRF52833 via UART)
I have read some threads that mention about DFU, Bootloader but I found it quite confusing to started..
I'm new at this topic so can you suggest for me an roadmap and keywords to explore this interest topic.
And what is the example in SDK16 that I can refer to?
Since it takes a long time for an answer, please answer in as much detail as possible. Thank you so much

[Jørgen Holmefjord]

Hi,

Serial DFU is described in the SDK documentation:

• Secure DFU Bootloader over Serial Link (UART/USB)
• Serial DFU protocol
• Bootloader and DFU modules

We do not have any official examples of serial DFU master, but one of my colleagues provided an example in this guide.

Best regards,
Jørgen 

[John12]

Hi, I followed the tutorial you recommened but I got a problem when trying to transfer zip file to nRF via BLE. DFU start Connecting then Disconnecting imediately

I used ble_app_uart hex file. Current firmware of my nRF is secure_bootloader_ble_s140_pca10100

Here is log on nRF connect

[John12]

Hi, problem was solved. I need to check SD id compatible with SoftDevice version

Now I have 2 question

1. How can I merge DFU in an example that not contain SoftDevice ??
2. When I try to FOTA, It request firmware need to contain SoftDevice

I want to use update an basic application such as Blinky (update) to replace current firmware such as (PWM)  

[Jørgen Holmefjord]

If you want to do firmware updates over BLE, you need to include the softevice in the application, as this is required by the bootloader to do the transfer of the image. You do not need to use/initialize the softdevice in your application, but you need to make space for it in flash. You also need to set aside a small amount of RAM for the MBR. See Adjustment of RAM and Flash memory for more details.

The new firmware does not need to contain a softdevice, but it must be build with flash configuration to not overwrite the existing softdevice, if you want to keep support for DFU over BLE. The blinky peripheral example in the SDK have projects for s140 softdevice, but the softdevice is not use in the application itself.