Server

rednet.open("top")

local function check_response()
        id, message = rednet.receive("response", 20480)
        print(message)
end

while true do
    print("Enter your command :")
    cmd = read()
    if cmd == "start" then
        print("starting command has been send !")
        rednet.send(5, cmd, "cmd")
        check_response()
    elseif cmd == "stop" then
        print("stoping command has been send !")
        rednet.send(5, cmd, "cmd")
        check_response()
    end
    print("Command succesfully send !")
    os.sleep(0.1)
end