TMS320F2800157-Q1: Handling of break field detection when implementing LIN using an SCI

yasushi hatakeyama

I am using TI’s TMS320F2800157-Q1 and implementing a LIN slave task using the SCI module, which is configured to use its FIFO.
Upon receiving a Break Field, a framing error is detected; I then execute `SCI_performSoftwareReset` to clear this error.
However, when the subsequent Sync Field arrives, the low-level signal from the Break Field is incorrectly interpreted as the start bit of the Sync Field.
What steps should I take to ensure that the next falling edge is correctly recognized as the start bit of the Sync Field?

2 days ago

0 Delaney Woodward 1 day ago

TI__Mastermind 27070 points

Hi Yasushi,

The SCI module from a hardware standpoint isn’t designed to be LIN protocol compliant. I would suggest switching to using the LIN module on this device if possible?

Best Regards,

Delaney

0 yasushi hatakeyama 1 day ago in reply to Delaney Woodward

Prodigy 60 points

Hi Delaney,
Thank you for your reply.
I would like to implement this using the SCI module.
I believe the issue can be resolved if I can reset the bit-by-bit state machine upon the reception of a break field.
Could you please tell me how to perform that reset?

0 Delaney Woodward 5 hours ago in reply to yasushi hatakeyama

TI__Mastermind 27070 points

Hi Yasushi,

You would have to have some idle time between the break field and the sync field of the LIN frame to allow the SCI time to clear the framing error and resynchronize. Other than that, I believe your software FE clear approach should work.

Best Regards,

Delaney

C2000™︎ microcontrollers

C2000 microcontrollers forum

TMS320F2800157-Q1: Handling of break field detection when implementing LIN using an SCI