How does the UART bootloader responds feedback?

[Wisse Pielage]

Posted on February 20, 2017 at 16:46

Hi,

We are designing a project where we would like to use the default bootloader on a LIN connection.

The MCU we plan on using is the STM32F030RC, with external LIN-driver.

The LIN-driver merges Tx & Rx, so everything send will be visible on the Rx.

How does the UART bootloader respond to its own ack/nack or data?

Does it get in a loop where it nack's its own data because it is not a known command?

Thanks in advance!

#stm32f030 #lin #bootloader

[Oliver Beirne]

Posted on February 20, 2017 at 16:56

Hello

I have moved your question to the

https://community.st.com/community/stm32-community/stm32-forum?sr=search&searchId=79af816d-ae78-426a-b02f-5a92a9337c2e&searchIndex=0

‌ where someone should be able to assist you.

Thanks

[Tesla DeLorean · Accepted solution]

Posted on February 20, 2017 at 17:59

It doesn't expect feedback, and will likely not function well if that occurs, either at the command and parameter level, or data.

The firmware times the 0x7F at 7E1 pattern, and responds with a 0x79

[Wisse Pielage]

Posted on February 21, 2017 at 09:44

Thanks for your fast response!

Looks like I have to write my own, or change the plans!

[Tesla DeLorean]

Posted on February 21, 2017 at 17:22

My advice on STM32 designs is not to do odd things with standard interfaces used for system loader functionality. ie have the USART go to an RS232 port or headers, don't connect it to a modem or GPS receiver

The F030 is likely pin/usart constrained, so I can see that as being an issue.