A PowerShell script to read serial data from any Arduino. Supports writing to CSV file (assuming Arduino sketch is programmed to do so).

Read-Serial-Data-Arduino.ps1

param(
    [Parameter(Mandatory=$true)][string]$PortName,
    [Parameter(Mandatory=$true)][int]$BaudRate,
    [Parameter()][string]$CsvPath = ""
)

# Initialize serial port communication
$port = New-Object System.IO.Ports.SerialPort
$port.PortName = $PortName
$port.BaudRate = $BaudRate
$port.Parity = [System.IO.Ports.Parity]::None
$port.DataBits = 8
$port.StopBits = [System.IO.Ports.StopBits]::One
$port.Handshake = [System.IO.Ports.Handshake]::None
$port.ReadTimeout = 10000 # milliseconds

$port.ReadBufferSize = 16384 # bytes
# Can handle ~1.4 seconds of buffered data at baud rate of 115200
# Or ~17 seconds of buffered data at baud rate of 9600

# Supported Baud Rates: 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 28800, 31250, 38400, 57600, 115200
# Formula: Seconds of data = (Buffer Size) / (Baud Rate / 10)

$port.DtrEnable = "true"
# This allows sending the "Data Terminal Ready Enabled", which is necessary (somehow) for reading serial data.
# Apparently it's used for auto-resetting the Arduino, although this script doesn't do that from basic testing.

try {
    $port.Open()
    Write-Host "Opened serial port $($port.PortName) using baud rate $($port.BaudRate)"

    if ($CsvPath.length -gt 0) {
        # Create a file writer handle
        $FullCsvPath = $(Join-Path (Resolve-Path .) $CsvPath)
        Write-Host $FullCsvPath
        $CsvWriter = [System.IO.StreamWriter]::new($FullCsvPath, $true)
        Write-Host "All data will be written to $CsvPath in comma-delimited CSV format"
    }

    # Discard any existing data in the buffer
    $port.DiscardInBuffer()

    # Read data continuously until an error occurs or no more data is available
    while ($port.IsOpen) {
        try {
            # Record starting read time
            $StartReadTime = Get-Date
            $SerialData = $port.ReadExisting()

            if ($CsvPath.length -gt 0) {
                $CsvWriter.Write($SerialData)
            }

            # Stream received data
            Write-Host $SerialData -NoNewLine
        } catch [System.TimeoutException] {
            Write-Host "Error: Did not receive any data after $($port.ReadTimeout / 1000) seconds"
        }
    }
} catch {
    Write-Host "Error: $($_.Exception.Message)"
} finally {
    # Close the CSV file writer (if present)
    if ($CsvWriter -ne $null) {
        $CsvWriter.Close()
        $CsvWriter.Dispose()
    }

    # Close the serial port and dispose of the handle
    if ($port.IsOpen) {
        $port.Close()
        $port.Dispose()
        Write-Host "Closed serial port $($port.PortName)"
    }
}

How to Use

1. Download this script onto your computer.
2. Find the COM port for your Arduino via the Device Manager or the Arduino IDE.
3. Find or set the baud rate for said COM port. If you don't know from your original sketch, type mode COM0 in command prompt, where COM0 is an example port.
4. Run a new PowerShell session as Administrator and type .\Read-Serial-Data-Arduino.ps1 "COM0" 9600 ".\data.csv", while changing the parameters for your use case.