Updating firmware (application) from nrf Toolbox for iOS works fine (hex file), trying to do it from an Android phone does not. The messages are "Starting DFU ..." then "Disconnecting" then "Upload Failed: GATT ERROR". Is th

[Michel]

Updating firmware (application) from nrf Toolbox for iOS works fine (hex file), trying to do it from an Android phone does not.

The messages are "Starting DFU ..." then "Disconnecting" then "Upload Failed: GATT ERROR".

I tried different settings with different number of packets but nothing seem to work.

I tried enabling/disabling "External MCU DFU". Disabling this gets into a loop

"Starting bootloader..." -> "Connecting..." -> "Starting DFU..." and repeats.

My guess it should be enabled.

The device announce DFU_S130_V1.0 if that says anything.

[Hung Bui]

Hi Michel, 

Please tell which phone did you test with ? 

Which SDK your bootloader based on and which Softdevice  ? 

[Michel]

Samsung Galaxy A5 and Samsung Galaxy Tab S2

Softdevice S130 V1.0

I guess the SDK the bootloader is from february 2017 ... I can attach the bootloader.hex file

3323.bootloader.hex

[Hung Bui]

Hi Michel, 

It's a pretty old softdevice and SDK. 

If you can capture a sniffer trace when the issue appear it would be nice. 

We have seen this issue on older Android model, and there wasn't a clear solution for it. Please search for GATT Error 133. We actually see less of this issue on more modern phone. Please try to test on other phone if possible.

When testing, please make sure you erase bonding on the phone, and try turn off and on Bluetooth before the test. 
Where did you find that option :  "External MCU DFU" ? Could you take a screenshot  ?

[Michel]

I ordered a nRF Dongle to capture a sniffer trace.

[Michel]

I got the dongle now and captured tries to dfu using android

Capture #1 "android_dfu_looping_no_settings.pcapng" 
Here I did not change any settings, nothing is enabled in settings.
This scenario loops the dfu process and firmware is not uploaded.

android_dfu_looping_no_settings.pcapng.zip

Capture #2 "android_dfu_external_mcu_dfu_on_gatt_error.pcapng"
In this scenario, I enabled External MCU DFU in the settings and
got a GATT Error.

android_dfu_external_mcu_dfu_on_gatt_error.pcapng.zip

[Hung Bui]

Hi Michel, 

Thanks for the sniffer trace. What I can find from the trace is that the nRF52 in both case crashed (reset) after receiving the BLE write command to switch to bootloader. (Master kept sendding BLE packet but slave didn't respond) 
I'm not sure why it worked when testing on iOS but doesn't work on Android (please take a sniffer trace with iOS DFU for comparison)

Could you check if the device get an assert and reset or not when you start the DFU ? You may need to follow this guide. 

If it doesn't reset or get an assertion, could you check the disconnect reason when the device get DISCONNECTED event ? 

Could you try testing with unmodified DFU buttonless and stock DFU bootloader ?