dfu init packet send error

[rajAsthana]

I am able to put my board(nrf52840) in DFU mode with buttonless code using Esp32 as controller.

The problem currently i am facing is to send a init packet to my nrf board at data point.

when ever i am trying to send an init packet, I didn't get any reply at my ESP32 board  and after some time my nrf board comes in application mode from DFU mode.

For reference i am attaching logs of my ESP32 board

20:44:24.078 -> Starting Arduino BLE Client application...
20:44:24.755 -> BLE Advertised Device found: Name: UART_DFU_Test, Address: c3:3e:a6:fb:ed:f4, serviceUUID: 0000fe59-0000-1000-8000-00805f9b34fb
20:44:24.755 -> Found our device! address: Forming a connection to c3:3e:a6:fb:ed:f4
20:44:24.789 -> - Created client
20:44:24.822 -> - Connected to server
20:44:25.469 -> - Found our Data service
20:44:25.469 -> - Found our characteristic....
20:44:25.469 -> - Found our DFU service
20:44:25.469 -> DFU service canIndicate....
20:44:25.537 -> Indicate callback
20:44:25.537 -> 20 01 01(Response from NRF52 to ESP32 corrospondance to 0x01 command )
20:44:32.153 -> 60 06 01 00 02 00 00 00 00 00 00 00 00 00 00 ((Response from NRF52 to ESP32 corrospondance to 60 01 command for select object))
20:44:35.154 -> sending create object command...
20:44:35.188 -> Indicate callback
20:44:35.188 -> 60 01 01 (Response from NRF52 to ESP32 corrospondance to 0x01, 0x01,0x90,0x00,0x0,0x0 command to create object)
20:44:35.188 -> Ready to send init Packet
20:44:35.188 ->

when i am trying to send init packet as show in log above nothing happens.

i stored the content of init packet in a local buffer in my code as shown below 

uint8_t emgPkt3[144] = {0x12,0x8D,0x01,0x0A,0x47,0x08,0x01,0x12,0x43,0x08,0x01,0x10,0x34,0x1A,0x05,0xCA,0x01,0xFE,0x95,0x03,0x20,0x20,0x28,0x20,0x30,0x20,0x38,0xF0,0xA2,0x03,0x42,0x24,0x08,0x03,0x12,0x20,0x65,0x2B,0xCB,0x9A,0xCA,0x79,0xC4,0x5C,0x99,0x81,0x98,0x06,0xF3,0x1E,0x3D,0x27,0xA7,0x08,0x69,0x20,0x20,0x94,0x51,0x7F,0x4B,0xD0,0x14,0x53,0x74,0x55,0x53,0xEF,0x48,0x01,0x52,0x040,0x80,0x01,0x12,0x20,0x10,0x20,0x1A,0x40,0x7B,0x14,0x2F,0xA8,0x3B,0xAA,0xB2,0x4B,0x84,0x5C,0x44,0x59,0xBF,0x05,0x24,0x5A,0xBF,0xDF,0x44,0x24,0x1F,0xC5,0xAE,0x3C,0xF6,0x5C,0x54,0xD0,0x3E,0x84,0xDB,0x04,0xD4,0x8B,0xA6,0x3B,0x64,0xE4,0x30,0x5E,0x8E,0x01,0xEB,0x47,0xDE,0x69,0x79,0x27,0x93,0x09,0xF3,0xE1,0xE2,0xF1,0x1B,0x73,0xE2,0x19,0x6B,0x2F,0xAB,0x1A,0x11,0x0E};

and sending four bytes at a time till all 144 bytes are completed.

can you suggest me where i am wrong?

Thanks 

Raj

[Hung Bui]

Hi Raj, 

Please clarify, at this stage: 

20:44:24.755 -> BLE Advertised Device found: Name: UART_DFU_Test, Address: c3:3e:a6:fb:ed:f4, serviceUUID: 0000fe59-0000-1000-8000-00805f9b34fb

It was the buttonless application running or it's the DFU bootloader running ? 

If it's your buttonless DFU application running you would need to switch it to the bootloader before you continue to send the init packet. 

After you have finished sending the init packet, you must send a 0x03 for the bootloader to start calculating the CRC. Please refer to the message chart here: 

https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.0.2/lib_dfu_transport_ble.html?cp=7_1_3_5_2_2_3#lib_dfu_transport_msc

Note that if you don't set the PRN it won't send the notification about PRN success. 

I would suggest to capture a sniffer trace of a successful DFU session from our App and compare it to your DFU update via the Esp32. 

Please also check the log on the bootloader to find if anything goes wrong. 

[rajAsthana]

Hi,

whenever I try to write on DFU packet characteristics, on ESp32 side we observer that code gets stuck at "m_semaphoreWriteCharEvt.wait("writeValue"); " 

Can you guide how to use sniffer trace to capture the actual data from the android app while DFU process? 

ty..

[Hung Bui]

Hi Raj, 
Please follow the instruction on the sniffer documentation. If you can't download the sniffer due to our current website issue please use the one I attached here. 
Basically you just need to select the advertiser you want to follow in wireshark (after you copy the ext_cap folder to wireshark as instructed in the documentation). 

I'm not familiar with your code m_semaphoreWriteCharEvt.wait("writeValue"); on the ESP32 so I can't really help here.