Tool/software:
Hi Sir :
The SCI module of the TMS320F28027 chip we are currently using has a low RX pin for some reason during transmission. Theoretically, this low level will trigger the SCIRXST.bit.BRKDT register in the 28027 chip to be set to 1,
But after testing, we found that only a very small number of chips produce this error flag bit. We would like to understand the mechanism of this flag bit generation (why is it low when I send it? Most boards do not produce this flag bit, so let's do some abnormal judgment processing).
Because according to the specifications (triggering when 10 BITs are detected) and the waveform we tested, it should be generated. Please help analyze and answer this question. Thank you.
Blue: Receive RX, yellow: Enable RE, red: Send TX
Note: (The high level stage of the yellow enable RE signal is the transmission stage). During the transmission stage, our RX becomes low level, which theoretically should generate the BRKDT flag. However, we have tested that only a very small number of boards produce this signal.
