function inter_parse(line)
  print("inter_parse: line="..line)

  line = string.sub(line, 1, string.find(line, "\r"))

  local cmd = nil;
  local i = string.find(line, ":")
  if i == nil then
    print("inter_parse: invalid line: no command, line="..line)
    return
  end
  local cmd = string.sub(line, 1, i - 1)
  print("inter_parse: cmd="..cmd)

  local args = {}
  last = i+1
  while i ~= nil do
    local key
    local value

    i = string.find(line, " ", last)

    arg = string.sub(line, last, i)
    print("inter_parse: arg: "..arg)
    j = string.find(arg, "=")
    if j == nil then
      key = arg
      args[key] = true
      print("inter_parse: key="..key.."=true")
    else
      key = string.sub(arg, 1, j-1)
      value = string.sub(arg, j+1)
      print("inter_parse: key="..key..", value="..value)
    end
    if i == nil then
      break
    end
    last = i + 1
  end

  return cmd, args
end

local cb
-- require('inter'); inter_init();
-- cmd:abc=123 xyz=qwe woot
function inter_on_line(line)
  print("line:"..line)

  local cmd, args = inter_parse(line)
  if cmd == nil then
    return
  end

--  print("cmd="..cmd)
--  for k, v in pairs(args) do
--    print(k.."="..tostring(v))
--  end
  if cb then
    cb(cmd, args)
  end
end

function inter_init(callback)
  -- uart.setup(id, baud, databits, parity, stopbits, echo)
  -- uart.setup(0, 115200, 8, 0, 1, 0)
  -- uart.setup(0, 9600, 8, 0, 1, 0)
  cb = callback

  tmr.alarm(0, 1000, 0, function() print("still alive!"); end)
  uart.on("data", "\r", inter_on_line, 0)
  print("inter ready: callback.."..tostring(cb))
end