Quote:
Originally Posted by knc1
That same behavior has had another (2) two reported causes -
Wrong interface voltage used with the serial adapter -
Serial adapter that takes an external reference to set the interface voltage and the source used had a lot of noise on it.
Since the poster did not include any detail other than "serial port" -
We don't even have any clues to guess from.
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Posters:
Context! Context! Context!
This is a technical forum that handles technical questions -
And most of the time, our crystal balls are off-line (crystal ball air-time is far too expensive).
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I had problems on some of my kindles (K4/K5) that were flaky using the GND pin/pad on the TTL serial connector. I got working using my full level-shifter circuit. Then I discovered that half the circuit was not needed (kindle Rx) if I used a solid grond, like the USB shell, or another obvious solid ground (3.3v tolerant Rx on the 1.8v input). So a good ground is very important, and the one on the connector is not a good ground in my experience. But more like NO output, not scramled characters. It looks like CR/LF are working (typical screen layout) so more like character set issues (perhaps triggered by a few bad "binary" characters). Caused by bad ground -- persistent until terminal reset...