SerialScope 0.2.2

A serial-port based oscilloscope

A serial port dual-channel oscilloscope. Python 3 only.

$ pip install SerialScope --user    # just for you

or,

$ sudo -E pip install SerialScope   # for all users

After installation, launch it.

$ serialscope

Path ~/.local/bin should be in your PATH environment variable.

or,

$ python3 -m SerialScope 

The default baud rate is 115200. The oscilloscope will automatically find any serial port which has arduino connected to it.

TODO/FIXME You can change these values from command line

usage: serialscope [-h] [--port PORT] [--baudrate BAUDRATE]

Arduino NeuroScope.

optional arguments:
  -h, --help            show this help message and exit
  --port PORT, -p PORT  Serial port.
  --baudrate BAUDRATE, -B BAUDRATE
                        Baudrate of Arduino board.

Dependencies

• pyserial
• pysimplegui
• screeninfo (optional)

How it works

This oscilloscope has two channels. It assumes that 1 byte of data is sent for each channel. If you are using arduino's analog pins to read data, then your resolution would be 5/255 volts.

Arduino board

Function analogRead returns 10 bit value i.e., between 0 and 1023. You should scale it to 255, cast it to char before writing to serial port. This is for efficiency. Sending 10 bits data requires sending 2 bytes. For 2 channels, this would slow down the sampling rate by 4X compared to when only 1 byte is sent per channel.

You can use following snippets in your sketch.

Make sure that your arduino is set to use maximum possible baud-rate. I have used 115200 baud rate.,

// Two critical functions.
char intToChar( int val)
{
    // analogRead is 10 bits. Change it to 8 bits.
    char x = (char) (255.0 * val/1023.0);
    return x;
}

void write_data_line( )
{
    // channel A is on pin A0 and channel B is on A1
    char a = intToChar(analogRead(A0));
    char b = intToChar(analogRead(A1));
    Serial.print(a);
    Serial.print(b);
    Serial.flush();
}

A sketch is available in SerialScopeArduino/ directory. Open it in your arduino IDE and upload to your Arduino board.