SCI transmit adds a "1" bit at the end of character in TMS570LS1227

Richard Derman2

In SCI multibuffer mode, when I transmit a set of characters, the first character is transmitted correctly, then subsequent characters have an extra "1" bit tagged on to the end of the stream. The Stop and Start bits are normal, parity is not enabled.

over 11 years ago

0 Jean-Marc Mifsud over 11 years ago

TI__Mastermind 22375 points

Richard,

Can you check the status of bit0 in SCIGCR1?
This bit is COMM MODE. With a value 0, you are in Idle-line mode, with 1 you are in Address-bit mode.
In address bit mode, the frame looks like:

Please let me know if this is what you are seeing.

0 Richard Derman2 over 11 years ago in reply to Jean-Marc Mifsud

Intellectual 260 points

Jean-Marc,

Thanks for the response. I found this out earlier today. Unfortunately, I had an earlier version of SPNU515, where the sense of SCIGCR1[0] was incorrect. Once I discovered that, no problems.

Rick

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SCI transmit adds a "1" bit at the end of character in TMS570LS1227