Hardware UART Invert

[Kinqdos]

Hey guys is it possible to use the UART inversion for hardware uart? I read that this isn't supported for SoftwareSerial, but nothing mentioned in the UART section.

[earlephilhower]

See #1443 . The HW UART doesn't do inversion.

[Kinqdos]

Maybe this helps https://talk.dallasmakerspace.org/t/raspberry-pi-pico-sbus-code-help/79375/6. The guy claims, that you can invert any gpio pin.

[earlephilhower]

Ah, did not think of that. The peripheral won't invert, but the pads can. I think this can easily be added to both SerialUART/PIO. I'll throw something together over the weekend and if you could give it a test it'd be great...

[Kinqdos]

I have to admit, that I only understand parts of what you saying. Im not really into those "technical" things like assembler registers or like anything mentioned in the datasheet. But im happy to test it with my sbus receiver :)

[earlephilhower]

Please give #2395 a try, @Kinqdos . I did a quick output test using a pulseview to check and it does seem to be inverting as expected with "idle" being LOW, not HIGH.

void setup() {
  Serial1.setInvertRX();
  Serial1.setInvertTX();
  Serial1.begin(115200);
}

int x = 0;
void loop() {
Serial1.printf("%d\n", x++);
delay(100);
}

[Kinqdos]

Tested it with my sbus receiver and it works fine! Thank you for the fast response and implementation!!! :)