Immibis peripheral "Speaker" keybord

--[[
        keys random
        by Big SHiny Toys
]]--

local function openDevice(sType)
    for i,v in pairs(rs.getSides()) do
        if peripheral.isPresent(v) and peripheral.getType(v) == sType then
            return peripheral.wrap(v),v
        end
    end
end

local function freq(key)
    return (2^((key-49)/12))*440
end

local key = 1
local pitch = freq(key)
local chan = 1
local speaker = openDevice("speaker")

if not speaker then
    error("no speaker found")
end

term.clear()

local function p()
    term.setCursorPos(1,1)
    term.clearLine()
    print(" key "..key.." pitch "..pitch)
end

local tKeys = {
    a = 40,
    w = 41,
    s = 42,
    e = 43,
    d = 44,
    f = 45,
    t = 46,
    g = 47,
    y = 48,
    h = 49,
    u = 50,
    k = 51,
    j = 52,
    o = 53,
    l = 54,
    p = 55
}

local tTimers = {}

local hang = 0.3

for k,v in pairs(tKeys) do
    print(k," ",v)
end

local offSet = 0

local numb = 0

while true do
    local event = {os.pullEvent()}
    if event[1] == "char" then
        if tKeys[event[2]] then
            local tab = os.startTimer(hang)
            tTimers[tostring(tab)] = numb
            speaker.start(numb,freq(tKeys[event[2]] + (offSet*12)))
            numb = numb + 1
            if numb > 7 then
                numb = 0
            end
        end
    elseif event[1] == "timer" then
        local st = tostring(event[2])
        if tTimers[st] then
            speaker.stop(tTimers[st])
            tTimers[st] = nil
        end
    elseif event[1] == "key" then
        if event[2] == 200 then
            offSet = offSet + 1
        elseif event[2] == 208 then
            offSet = offSet - 1
        end
    end
end

--[[
while true do
    p()
    local event = {os.pullEvent()}
    if event[1] == "char" then
        if event[2] == "u" then
            key = key + 1
            pitch = freq(key)
            speaker.start(chan,pitch)
        elseif event[2] == "d" then
            key = key - 1
            pitch = freq(key)
            speaker.start(chan,pitch)
        elseif event[2] == "s" then
            speaker.stop(chan)
        elseif event[2] == "p" then
            for i = 1,30000 do
                speaker.start(chan,i)
                term.setCursorPos(1,1)
                term.clearLine()
                print(" key "..key.." pitch "..i)
                sleep(0.001)
            end
        end
    end
end
]]--