Secure DFU without Flow control (SDK 15.2)

[Goudra]

Hi All,

I have implemented the code for MASTER serial DFU in ST micro controller. which can send the app .bin file. I'm using 57600 baud and disable the flow control.

I'm getting  Unexpected OP_CODE error. Is it because of data loss?

Can we send data without setting Hardware flow control? Because in our custom board don't have Hardware flow control pins.

How we can achieve proper communication between BLE devices and ST uC?

Any baud rate issue?

Please let us know any suggestions.

Thanks,

Basava.

[Goudra]

Hi,

Now i'm sending data at 9600 baud rate using nrfutils command from the Prompt. Its working. But we have implemented same in St controller side(C code), here we saw same issue with hardware fault. 

Then we log the working CMD prompt data, we observe the log packet by packet. While sending  Firmware packet, after every 3 packet its need 200msec delay. (I really dont know why this delay is needed after 3packet?).

So, we considered it in our code and implemented it. Now issue got resolved. We struggled a lot to find out this and took 2 week of time. 

To verify that delay, we tested with different baud like 4800. Now it is taking 400msec after every 3 packet.

and for 14400baud it is taking ~150msec delay. 

I request you, Can you please let us know why the bootloader needs a delay after 3 packet? and

why the delay is changing based on the baud rate?

Because of this delay requirement some time its not working with 57600baud.

please find log file above "" Baudrate_9600.htm ""

Please let us know the delay requirement.

Thanks ,

Basava

[Goudra]

Hi,

Is there any suggestion on this?

Regards,

Basava.

[bjorn-spockeli]

As suggested by my colleague in this case, we were expecting the opposite behaviour, i.e. that you would need a longer delay with increasing baudrate. We kindly ask you to use the hardfault handling library to identify the cause of the hardfault in the bootloader. 

We would also like to see traces of the UART lines during the transfer so that we can verify that the  data is transferred correctly.