Posted on December 09, 2016 at 11:47The original post was too long to process during our migration. Please click on the attachment to read the original post.
basically (looking at your short version only) HAL_UART_Transmit_IT() is not blocking so you are writing to buffer (the second sprintf) before the first lot of data is transmitted.
You have 3 options:
wait for the 1st transmission to finish before writing to the buffer,
set up a system where you either use separate buffers or unused parts of the buffer the 2nd time