GATT to Mesh DFU Upgrade

[Aftab]

Hello,

We have a GATT based product. It's using SDK16 and softdevice v7.0.1. It's using secure DFU to upgrade. Now we are developing new firmware based on Mesh 4.0.

We want our devices to be able to be upgraded from GATT to Mesh without using JTAG programmer, i.e, by DFU through OTA. How to achieve this? 

[Joakim Jakobsen]

Hi.

Some more information could be useful here. Do you want your devices to support Mesh DFU after upgrading the FW? That case you also need to change the bootloader.
How many devices is going to be part of the network?
When changing to the new Mesh FW, you should do a BL + SD update first, to wipe the old app. Then, when all the GATT devices is updated with the new Mesh BL, you can perform a Mesh DFU with the new application to the entire network.

We haven't tested this before, so there might be some unexpected issues here. Do you have the possibility to recover the devices if the DFU fail?

Br,
Joakim

[Aftab]

1. Yes, we want our devices to support mesh DFU after the upgrade.
2. We want to have maximum number of devices possible
3. I have done SD + app through DFU, how to do BL + SD? Will this wipe out the earlier (GATT) boot-loader as well?
4. If GATT DFU gets wiped out during mesh change, and DFU process is unsuccessful, I don't think we can recover the device. 
5. If GATT DFU remains intact during mesh change, that will waste a part of memory areas for ever?

[Joakim Jakobsen]

Thanks.

Aftab said:

We want to have maximum number of devices possible

The theoretical maximum of Mesh nodes in a single network is 32768.

Aftab said:

If GATT DFU gets wiped out during mesh change, and DFU process is unsuccessful, I don't think we can recover the device. 

If you don't have the possibility to recover the devices, I will forward this internally to see if there is someone that have tested this before and can give some pointers.

Br,
Joakim

[Aftab]

Hi,

That will be a great help if somebody can test this and possibly come up with an example code. May be many other people will be looking for a solution to this problem.

Thanks.