No transport to DfuTarg observed after "Enabling DFU Bootloader..."

[Ray]

First attempt at implementing buttonless dfu; assistance would be greatly appreciated. Using SDK v11 + s130 + nRF51822.

Please note that iphone screen captures supporting my observations can be seen here: https://goo.gl/VlYdBY

I wrote a bootloader, and successfully installed it with sd + app. It seems to be operating well and I'm able to debug, so I am capable of execution flow trace.

I created an app-only zip with good start packet using nrfutil, and added it to NRF Toolbox iOS app as a user file.

I start up my device, which is advertising for dfu properly.

In NRF Toolbox I select my file, then select my device as the target. I then tap "Upload".

The ios App begins the process. It quickly says "Starting update" followed by "Enabling DFU Bootloader...", and then it just sits there forever.

In debugging on the device, I can see that I get all the way through dfu_transport_update_start just fine, and at this point I'm in the bootloader.c wait_for_events() loop as I should be. (It eventually times out properly.)

However, oddly, while the phone is sitting there "Enabling DFU Bootloader...", the device never reaches ble_evt_dispatch() in the dfu transport - not a single time - indicating to me that the phone doesn't seem to be connecting into my device to initiate the transport.

When I use nRF Connect to see what's going on, I do see DfuTarg being advertised. When I Connect to it, I see "Legacy DFU Service" as the primary service. When I open the service, I see Legacy DFU Packet, Control Point, and Revision. (See photos for details.)

The encouraging thing is that when I do use nRF Connect to examine these things, I DO nicely get events coming into the handler at ble_evt_dispatch() within dfu_transport_ble.c. However, as I said, I get nothing coming into that handler as triggered by nRF Toolbox's DFU process.

(It is a bit odd that these things are called "Legacy DFU" given that I'm using the up-to-date SDK and the up-to-date nRF Toolbox & Connect apps. Perhaps a better version must be coming in sdkv12?)

In any case, as I said, the DFU seems to be starting nicely, but I'm blocked at this point given that the BLE transport doesn't seem to be being kicked off.

Any thoughts about what to try next would sincerely be appreciated; thanks for your time.

[Hung Bui]

It has been a long cases and I'm not sure which question has already been solved and which is still pending. But I can provide some information:

• If the device is not bonded to a central, when it switch to bootloader, we will try to advertise when in bootloader mode with Address + 1. This is explained at question I here.

• The nRFToolbox app or the nRF Connect should be able to automatically detect this and connect to the +1 address. [UPDATE]This is wrong, nRFToolbox and nRFConnect now only look for same address not the +1 address.

• the peer_data is the bonding information and central address that we pass from the application to the bootloader so that the phone can rebond when the bootloader is running. This is also explained in the FAQ linked above.

• We call the current DFU "Legacy DFU" because of the new more secured DFU is coming in SDK v12 very soon. Unfortunately, it's not backward compatible.

[seajayshore]

Hi Hung,

I've been away and just come back to this. Thanks v. much for all the clear information. I think you have explained exactly what is happening.

I will look at updating/changing the way our mbed app launches bootloader so we can pass information, but until then everything is working fine since we knew about the +1 address changing.

Thanks for confirming that the nRF Toolbox is just now working with the address change, that explains the problems I was having.

Thanks again!