Hi Zakaria Taleb Bendiab,
Actually in the LPC1549 STAT register description already give you answer.


So, don't care about the STAT ACKerror, after you send the CAN data successfully, these errors will be cleared automatically.
Wish it helps you!
If you still have question about it, please kindly let me know!
Have a great day,
Kerry
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
----------------------------------------------------------------------------------------------------------------------