Receive input via serial

[medc]

I am using the code from Example 2 in this post: Serial Input Basics - updated to read data coming via serial. I'm using an ESP32 using Arduino framework on PlatformIO.

The code below is only allowing me to use keyboard input but I would like to send commands from a Qt program using QSerialPort to write("hello").

Any suggestions on how to modify the code?

const byte numChars = 32;
char receivedChars[numChars];
boolean newData = false;
void recvWithEndMarker();
void showNewData();

void setup() {
    Serial.begin(9600);
    Serial.println("");
}

void loop() {
    recvWithEndMarker();
    showNewData();
}

void recvWithEndMarker() {
    static byte ndx = 0;
    char endMarker = '\n';
    char rc;

    while (Serial.available() > 0 && newData == false) {
        rc = Serial.read();

        if (rc != endMarker) {
            receivedChars[ndx] = rc;
            ndx++;
            if (ndx >= numChars) {
                ndx = numChars - 1;
            }
        } else {
            receivedChars[ndx] = '\0';  // terminate the string
            ndx = 0;
            newData = true;
        }
    }
}

void showNewData() {
    if (newData == true) {
        Serial.print("This just in ... ");
        Serial.println(receivedChars);
        newData = false;
    }
}

[medc]

I have opted for an alternative code and it is now working for me:

char buffer[16];
void process();

void setup() {
    Serial.begin(500000);
    Serial.flush();
}

void loop() { process(); }

void process() {
    while (Serial.available() > 1) {
        Serial.readBytesUntil('\n', buffer, 16);
        Serial.println(buffer);
    }
}

[drmpf]

Check out my Arduino Software Solutions for lots of alternatives for reading text from Serial.
Both blocking and non-blocking.
Not clear from your post if you are reading text (null terminated) or just bytes of data.

[Power_Broker]

You can easily interface Python and your Arduino using the compatible libraries pySerialTransfer and SerialTransfer.h (respectively). pySerialTransfer is pip-installable, SerialTransfer.h is installable via the Arduino IDE, and both come with many examples.

Basically, these libraries automatically packetize and parse USB/Serial data for fast and reliable communication without the hassle!

[medc]

@Power_Broker I wonder if Python would be fast enough to handle the bandwidth. I will need 18 kilobytes per second from a 24bit ADC at 250 samples per second x 24 channels (TI ADS1299 daisy chained x 3). Do you think?