Hi
We have a legacy product with around 100.000 active devices. We still need to distribute new firmware releases, and we are using the "Chained DFU" app for this purpose.
In the zip distribution package there is a 14 bytes "application.dat" file describing the image. The most important here is the CRC16 checksum. The old build script produces this zip-package by using nrfutil.exe:
nrfutil dfu genpkg --application application.hex application.zip
But the new nrfutil available for download does not support the nrfutil dfu genpkg command. :-(
Instead I have found following command to create the release package:
nrfutil pkg generate --hw-version 51 --sd-req 0x87 --application-version 1234 --app-boot-validation NO_VALIDATION --application application.hex application.zip
However, this command produces an application.dat file which is much more complex that the old one. As I understand it is a protobuf encoded structure holding additional data compared to the old format. The most important thing is that we were using a CRC16 for validating the image, and the new method generates a SHA256 hash. Our bootloader does not support this format.
Questions:
1. Is the old nrfutil.exe program producing the 14 byte application.dat file still available? Which versions will work?
2. is it possible to let the new nrfutil generate release packages with the 14 byte application.dat file?
Thanks in advance.
Kasper
