main

local mon = peripheral.wrap("top")

local t = {
          {text = "help", ymin = 3, ymax = 6, xmin = 8, xmax = 16, txCol = colours.black, bgCol = colours.lime}
}

function writeButton(_table)
  for i,v in pairs(_table) do
    mon.setCursorpos(v.xmax, v.ymin)
    mon.write(v.text)
    mon.setTextcolour(txCol)
    mon.setBackgroundcolour(bgCol)
  end
end

while true do
  writeButton(t)
end