local gfx <const> = playdate.graphics
local controlY = 0

local crankY = 0

function updateMenu()
    gfx.clear(gfx.kColorBlack)
    -- input 
    if playdate.buttonJustPressed(playdate.kButtonUp) then
        crankY -= 1
    elseif playdate.buttonJustPressed(playdate.kButtonDown) then
        crankY += 1
    end

    gfx.fillRect(0,controlY + (10 * crankY),50,10)
end