DFU OTA Firmware Image for production

[Samuele Forconi]

Hi, I've an application developed with SDK v8.0.0 and S110 v8, that is using the bootloader to start the main firmware and to start the DFU OTA (in case the user request to do a firmware upgrade).

My development system is Linux, with gcc and JLinkExe to load the bin files on the nRF.

I'm testing the system doing these steps:

1. Compile the bootloader and the application firmware.

2. Flash the Softdevice at address 0x00000000.

3. Flash the Bootloader at address 0x0003B000 (bootloader is configured for 20KB).

4. Write UICR.CLENR0 (0x18000), write UICR.BOOTLOADERADDR (0x3B000).

5. nRF starts advertising with the DFU service.

6. Load the main application firmware using nRF Toolbox iOS app.

Using this procedure, the application firmware starts correctly and I can use my firmware and also reload the same firmware (just for test) using the nRF Toolbox app.

This procedure is long, so I decided to dump the whole flash of the nRF using JLinkExe to use as an image for the next devices:

JLinkExe> savebin /home/samuele/flash.bin 0x00000000 0x40000

I then load the created image on another nRF board (using the loadbin command of JLinkExe), the application starts correctly but I'm no more able to load the same firmware via the nRF Toolbox app because it says "Error on Init packet. Operation failed."

Since the only things that change between the two nRF boards are some values set in the UICR.CUSTOMER registers (we use UICR.CUSTOMER for model, serial numbers, etc), I tried to set the UICR.CUSTOMER of the second board to the same values as that in the first board, then I reset the board and try to load the firmware again: now everything goes well and the firmware is upgraded with the nRF Toolbox app.

Now, I would like to know why the differences in the UICR.CUSTOMER registers are causing problems with the init packet of the bootloader?

What kind of checks are performed on the init packet beyond those documented on the SoftDevice Init Packet documentation?

How can I create a dump of the flash memory of the nRF so that I do not have to load my application firmware via BLE?

Thanks for any suggestions.

Samuele.

[oceanide]

My suggestion is not what you want. :)

How about merging all three binaries (softdevice, bootloader, and application) for production and then downloading merged binaries via JLink.

The following link shows how to merge hex files:

devzone.nordicsemi.com/.../

When I tested before, merged binary always stay in "DfuTag" without below changes: devzone.nordicsemi.com/.../

[Hung Bui]

@Samuele: I assume you use JLink to write to UICR.CUSTOMER (not by using attribute from the code)?

When do you receive "Error on Init packet. Operation failed." ? Before start sending image, or after ?

If it's after, then it could be a chance the CRC of the image is not matched.

If it's before, have you made sure you haven't touched/overwritted the user UICR area where device type and revision is stored ? (0x10001080). Usually it's leave as 0xFFFF to accept any device type and revision. Please see here.

[Samuele Forconi]

Yes, I've just checked the problem was that. The UICR_CUSTOMER_DEVICE_INFO_OFFSET is by default set to 0x00, and we are currently using the first 8 UICR.CUSTOMER registers for our settings. So when I overwrite the values in those registers, the DFU Init Packet did not match anymore with the 0xFFFF values of the default Device Type/Revision. I've set the UICR_CUSTOMER_DEVICE_INFO_OFFSET to 0x7C to use the last UICR.CUSTOMER register for those informations and now ot works correctly.

Thanks for your help.

[Hung Bui]

Problem was fixed, quoted Samuel:

I've just checked the problem was that. The UICR_CUSTOMER_DEVICE_INFO_OFFSET is by default set to 0x00, and we are currently using the first 8 UICR.CUSTOMER registers for our settings. So when I overwrite the values in those registers, the DFU Init Packet did not match anymore with the 0xFFFF values of the default Device Type/Revision. I've set the UICR_CUSTOMER_DEVICE_INFO_OFFSET to 0x7C to use the last UICR.CUSTOMER register for those informations and now ot works correctly.

[khan_khan]

how to set it ?