RFtools Tele sender

for k,v in pairs(rs.getSides()) do
  if peripheral.getType(v) == "monitor" then
    mon = peripheral.wrap(v)
  end
end
for k,v in pairs(rs.getSides()) do
  if peripheral.getType(v) == "modem" then
   rednet.open(v)
  end
end

function drawMon()
  mon.setBackgroundColor(colors.black)
  mon.clear()
  x,y = mon.getSize()
  buttonNo = 0
  for yc = y,1,-1 do
    buttonNo = buttonNo + 1
    if yc%2 == 1 then
      mon.setBackgroundColor(colors.purple)
      mon.setTextColor(colors.yellow)
    else
      mon.setBackgroundColor(colors.yellow)
      mon.setTextColor(colors.purple)
    end
    for xc = 1,x do
      mon.setCursorPos(xc, yc)
      mon.write(" ")
    end
  mon.setCursorPos(x/2+1,yc)
  mon.write(tostring(buttonNo))
  end
end

if fs.exists("floor") then
  file = fs.open("floor", "r")
  floor = file.readAll()
  file.close()
else
  term.clear()
  term.setCursorPos(1,1)
  print("Which number will this be on the monitor?")
  write("> ")
  floor = read()
  file = fs.open("floor", "w")
  file.write(floor)
  file.close()
  term.clear()
  term.setCursorPos(1,1)
  print("Thank you.")
  sleep(1)
  term.clear()
  term.setCursorPos(1,1)
end

while true do
  drawMon()
  event, side, xTouch, yTouch =os.pullEvent("monitor_touch")
  buttonNo = y - yTouch + 1
  touchData = {
    sender = floor,
    destination = tostring(buttonNo)
  }
  rednet.broadcast(textutils.serialize(touchData), "teleport")
end