How can I make copy about UART_TX_FIFO in Arduino skatch?

[Galilei11]

I need to catch and store all of characters coming out UART0 tx pin, and send them to another direction.
It have to do inside ESP, with software, because no free pin on ESP already (read back tx pin).
I think, if I can get every characters when is written to UART_TX_FIFO it can solve this problem.
But I dont know how, any idea?

[Links2004]

is it needed to do it register level?
simple create a class with stream interface.

HardwareSerial mirror(&Serial);

class SerialMirror: public Stream {
        HardwareSerial * _serial;
        SerialMirror(Serial * s) {
            _serial = s;
        }

        size_t write(const uint8_t *data, size_t size) {
             /// add code for your mirror here
            return _serial->write(data, size);
        }

        size_t write(uint8_t data) {
             /// add code for your mirror here
            return _serial->write(data);
        }

        int available() {
            return _serial->available();
        }

        int read() {
            return _serial->read();;
        }

        int peek() {
            return _serial->peek();
        }

        void flush() {
            _serial->flush();
        }
}

usage:

mirror.println('test');

[Galilei11]

thx, I will test it
but I am beginner yet, I started 2 month ago with ESP and Arduino, I try to understand and use it :)
how do you think: register level?

[me-no-dev]

@Links2004 I think he means that he wants to output at two locations at the same time.
For example: mirror.println(blah); to actually print to Serial and a Client (or some other destiantion)

[Links2004]

@me-no-dev yes think so, that is why I write `add code for your mirror here`` as comment in the code ;)

[tzapu]

@Links2004 will this make it possible for instance to stream serial to websockets? got any sample of that somewhere? :)

[Links2004]

@tzapu yes you can write a class that can "print" to websocktes in the same way, or eaven combine them to print to Serial and WS.
for many small prints I recommend the usage of the Async mode for websocktes or it will be slow.

class SerialMirror: public Stream {
        WebSocketsServer* _ws;
        SerialMirror(WebSocketsServer * s) {            _ws = s;        }

        size_t write(const uint8_t *data, size_t size) {    _ws->broadcastTXT(data, size); return size;        }
        size_t write(uint8_t data) {            return _ws->broadcastTXT(data);    return 1;    }

        int available() { return 0;  }
        int read() {    return -1;    }
        int peek() {    return -1;    }
        void flush() {       }
}

[tzapu]

hi, thank you very much for the hints, i assume i can combine the two above to proxy reading from serial to websockets... need to learn more :D

on second thought, do i need the stream interface if i m just reading and passing on to websockets? probably for simplicity it s better and i can just add the sending to the read method, maybe with some buffering ...

[Links2004]

yes for serial to websockets bridge you not need a stream interface for websockets .
simple buffering:

    Serial.setTimeout(200);
    String line = Serial.readStringUntil('\n');
    if(line.length() > 0) {
        // add back line ending
        line+='\n';
        ws->broadcastTXT(line);
    }

sends all 200ms (when data is there) or on every line ending.

[tzapu]

how cool is that :D
thank you very much

[tzapu]

@Links2004 this seems to be missing some strings at 115200, is there something i can do to make it more reliable?
p.s. i don t know yet, and i should check, if it is missing while reading or it s missing while sending over websockets... i ll check and be back

[tzapu]

@Links2004 , double checked, it seems it s missing strings when reading from serial.
cand i make it more reliable somhow?
thanks for all your help

my loop looks like this currently

void loop() {
  Serial.setTimeout(200);
  String line = Serial.readStringUntil('\n');
  if (line.length() > 0) {
    // add back line ending
    line += '\n';
    webSocket.broadcastTXT(line);
    Serial.print(line);
  }
  webSocket.loop();
}

[Links2004]

so you not get echoed back all data?

you can try:

void setup() {
 ....
 Serial.setTimeout(200);
}

void loop() {
    webSocket.loop();
    if(Serial.available()) {
        String line = Serial.readStringUntil('\n');
        if(line.length() > 0) {
            // add back line ending
            line+='\n';
            ws->broadcastTXT(line);
        }
    }
}

[tzapu]

nop, somhow it s eating characters.

tried with timeout in setup, still no go

connecting to 
emoncms.org
RequHTTP/1.1 200 OK
Date: Wed, 17 Feb 2016 17:29:59 GMT
Server: Apache/2.2.22 (Ubuntu)
X-Powentent-Length: 2
ok

that should have the full url there somewhere and headers, etc

[tzapu]

i have also tried without timeout, larger timeout, still the same.
a 500ms timeout does seem to make it a bit better, but still misses some stuff

[tzapu]

this seems to yield some better results on some fast tests, but i m not convinced it would hold as no timeouts, no buffering, etc

void serialEvent() {
  while (Serial.available()) {
    char inChar = (char)Serial.read();
    if (inChar == '\n') {
      stringComplete = true;
      return;
    } else {
      inputString += inChar;
    }
  }
}


void loop() {
  serialEvent();
  if (stringComplete) {

    String line = inputString;
       // clear the string:
    inputString = "";
    stringComplete = false;

    //line += '\n';
    webSocket.broadcastTXT(line);
    Serial.print(line);
  }
}