Powershell beep piano

12 Jan 2025 - jhunter

Sources

https://stackoverflow.com

https://devblogs.microsoft.com

https://www.youtube.com

https://worldradiohistory.com

Summary

This blog post presents a function I created which turns the keyboard into a very inefficient piano.

As the link from stackoverflow above explains, the console beep is not intended for making music.

Instead, the purpose of this function is to demonstrate how to make powershell react to key presses, thanks to the $host variable.

Using the function

Import the function into powershell.exe or pwsh.exe (but not the ISE).

The console beep can be controlled in two ways: the frequency and the length of the beep. The function defines the frequency of middle C in Hertz. The length can be changed but defaults to 600 milliseconds.

With this function, you get one octave of musical notes. The computer keyboard keys:

 WE TYU
ASDFGHJK

correspond to the piano keys:

 CD FGA   (sharps)
CDEFGABC

The function

function james-play-piano{

    param(
        [int][Parameter(Mandatory = $false, Position=0)]$length
    )


    $middlec = 261.625565
    if(!$length){
        $length = 600
    }
    
    while ($true){
        if($Host.UI.RawUI.KeyAvailable -and ($key = $Host.UI.RawUI.ReadKey("AllowCtrlC,NoEcho,IncludeKeyUp")) ){
    
            if($key.ControlKeyState -eq "LeftCtrlPressed, NumLockOn"){
                $c = $middlec / 2
            }
            elseif($key.ControlKeyState -eq "RightCtrlPressed, NumLockOn"){
                $c = $middlec * 2
            }
            else{
                $c = $middlec
            }
    
            switch($key.VirtualKeyCode){
                81 {$play = $c} # q key on a French keyboard
                90 {$play = ($c * [math]::pow(2,(1/12)) ) }
                83 {$play = ($c * [math]::pow(2,(2/12)) ) }
                69 {$play = ($c * [math]::pow(2,(3/12)) ) }
                68 {$play = ($c * [math]::pow(2,(4/12)) ) }
                70 {$play = ($c * [math]::pow(2,(5/12)) ) }
                84 {$play = ($c * [math]::pow(2,(6/12)) ) }
                71 {$play = ($c * [math]::pow(2,(7/12)) ) }
                89 {$play = ($c * [math]::pow(2,(8/12)) ) }
                72 {$play = ($c * [math]::pow(2,(9/12)) ) }
                85 {$play = ($c * [math]::pow(2,(10/12))) }
                74 {$play = ($c * [math]::pow(2,(11/12))) }
                75 {$play = ($c * [math]::pow(2,(12/12))) }
                default {$play= $null}
            }
            
            if($play){
                Write-Host "$(get-date -format "yyyy-MM-dd HH:mm")`tPlaying key $($key.VirtualKeyCode), frequency : $($play)"
                try{
                    [console]::beep($play,$length)
                    Start-Sleep -Seconds 1
                }
                catch{
                    Write-Host "$(get-date -format "yyyy-MM-dd HH:mm")`tFailed to play tone" -ForegroundColor Red
                }
            }
        }
    }
}