main.rb

#!mruby
#GR-CITRUS Version 2.50

# GR-CITRUS and WA-MIKAN MQTT Client Sample program
# http://gadget.renesas.com/ja/product/citrus.html
# http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html

WIFI_SSID = "enter_your_wifi_ssid"
WIFI_PASS = "enter_your_wifi_pass"

# MODE – Make IoT a reality for your business
# https://www.tinkermode.com/
MQTT_SERVER = "mqtt.tinkermode.com"
MQTT_PORT = 1883    # TCP=1883, SSL=8883
MQTT_KEEP_ALIVE = 60
USER_NAME = "enter_your_device_id"
PASSWORD = "enter_your_device_API_key"
PUB_TOPIC = "/devices/#{USER_NAME}/event"
SUB_TOPIC = "/devices/#{USER_NAME}/command"

ESP8266_EN = 5
LIGHT_LED = 17
BUTTON_PIN = 10

DEBUG = false

def wait_response(expected_value, timeout)
  end_time = millis() + timeout

  result = ""
  while end_time > millis()
    if @wifi.available() > 0
      result = result + @wifi.read()
      delay 10
    end
    if result.include?(expected_value)
      puts result if DEBUG
      return true
    end
  end

  puts result if DEBUG
  return false
end

def dump_packet_string(packet)
  puts packet.length
  debug = ""
  packet.chars { |ch| debug += ch.ord.to_s(16) + " " }
  puts debug
end

def build_mqtt_connect_packet(params)
  keep_alive = params[:keep_alive] || 60
  client_id = params[:client_id] || ""
  will_topic = params[:will_topic] || ""
  will_msg = params[:will_msg] || ""
  user_name = params[:user_name] || ""
  password = params[:password] || ""

  # Calculate Remaining Length
  remaining_length = 10   # header length
  remaining_length += (2 + client_id.length)
  remaining_length += (2 + will_topic.length + 2 + will_msg.length) if will_topic.length > 0 && will_msg.length > 0
  remaining_length += (2 + user_name.length + 2 + password.length) if user_name.length > 0 && password.length > 0

  # 3.1 CONNECT – Client requests a connection to a Server
  # 3.1.1  Fixed header
  # MQTT Control Packet type
  result = 0x10.chr

  # Remaining Length -  see section 2.2.3.
  len = remaining_length
  loop do
    encoded_byte = len % 128
    len = len.div 128
    encoded_byte = encoded_byte | 128 if len > 0
    result += encoded_byte.chr
    break unless len > 0
  end

  # 3.1.2 Variable header
  # Protocol Name
  result += 0x00.chr
  result += 0x04.chr
  result += "MQTT"

  # Protocol Level - MQTT 3.1.1
  result += 0x04.chr

  # Connect Flags
  connect_flag = 0x02
  connect_flag |= 0x04 if (will_topic.length > 0 && will_msg.length > 0)
  connect_flag |= 0xC0 if (user_name.length > 0 && password.length > 0)
  result += connect_flag.chr

  # Keep Alive
  result += 0x00.chr
  result += keep_alive.chr

  # 3.1.3 Payload
  # 3.1.3.1 Client Identifier
  result += (client_id.length >> 8).chr
  result += (client_id.length & 0xFF).chr
  result += client_id

  # 3.1.3.2 Will Topic
  # 3.1.3.3 Will Message
  if (will_topic.length > 0 && will_msg.length > 0)
    result += (will_topic.length >> 8).chr
    result += (will_topic.length & 0xFF).chr
    result += will_topic
    result += (will_msg.length >> 8).chr
    result += (will_msg.length & 0xFF).chr
    result += will_msg
  end

  # 3.1.3.4 User Name
  # 3.1.3.5 Password
  if (user_name.length > 0 && password.length > 0)
    result += (user_name.length >> 8).chr
    result += (user_name.length & 0xFF).chr
    result += user_name
    result += (password.length >> 8).chr
    result += (password.length & 0xFF).chr
    result += password
  end

  dump_packet_string(result) if DEBUG
  return result
end

def build_mqtt_publish_packet(params)
  topic = params[:topic] || ""
  message = params[:message] || ""

  # 3.3 PUBLISH – Publish message
  # 3.3.1 Fixed header
  result = 0x30.chr   #  DUP=0, QoS=0 (At most once delivery), RETAIN=0
  result += (topic.length + message.length + 2).chr

  # 3.3.2  Variable header
  # 3.3.2.1 Topic Name
  result += (topic.length >> 8).chr
  result += (topic.length & 0xFF).chr
  result += topic

  # 3.3.3 Payload
  result += message

  dump_packet_string(result) if DEBUG
  return result
end

def build_mqtt_subscribe_packet(params)
  topic = params[:topic] || ""

  # 3.8 SUBSCRIBE - Subscribe to topics
  # 3.8.1 Fixed header
  result = 0x82.chr
  result += (topic.length + 5).chr

  # 3.8.2 Variable header
  # Packet Identifier set to 0x1
  result += 0x00.chr
  result += 0x01.chr

  # 3.8.3 Payload
  # Length
  result += (topic.length >> 8).chr
  result += (topic.length & 0xFF).chr
  result += topic

  # Requested QoS = 0
  result += 0x00.chr

  dump_packet_string(result) if DEBUG
  return result
end

def mqtt_request(packet, expected_value)
  @wifi.print("AT+CIPSEND=#{packet.length}\r\n")
  System.exit "AT+CIPSEND failed" unless wait_response("OK\r\n>", 5000)
  @wifi.print(packet)
  wait_response(expected_value, 10000)
end

# setup
[ESP8266_EN, LIGHT_LED].each { |pin| pinMode(pin, OUTPUT) }
pinMode(BUTTON_PIN, INPUT_PULLUP)

puts "ESP8266 Reset..."
[LOW, HIGH].each do |value|
  digitalWrite(ESP8266_EN, value)
  delay 500
end

puts "WiFi Connecting..."
@wifi = Serial.new(3, 115200)
@wifi.print("AT+CWMODE=1\r\n")
System.exit "AT+CWMODE failed" unless wait_response("OK", 1000)

@wifi.print("AT+CWJAP=\"#{WIFI_SSID}\",\"#{WIFI_PASS}\"\r\n")
System.exit "AT+CWJAP failed" unless wait_response("OK", 10000)

if (MQTT_PORT == 1883)
  puts "TCP Start..."
  @wifi.print("AT+CIPSTART=\"TCP\",\"#{MQTT_SERVER}\",#{MQTT_PORT}\r\n")
  System.exit "AT+CIPSTART failed" unless wait_response("OK", 5000)
else
  puts "SSL Start..."
  @wifi.print("AT+CIPSSLSIZE=4096\r\n")
  System.exit "AT+CIPSSLSIZE failed" unless wait_response("OK", 1000)

  @wifi.print("AT+CIPSTART=\"SSL\",\"#{MQTT_SERVER}\",#{MQTT_PORT}\r\n")
  System.exit "AT+CIPSTART failed" unless wait_response("OK", 5000)
end

puts "MQTT Connect - #{MQTT_SERVER}"
packet = build_mqtt_connect_packet(keep_alive: MQTT_KEEP_ALIVE, user_name: USER_NAME, password: PASSWORD)
System.exit "CONNACK failed" unless mqtt_request(packet, "+IPD,4:" + 0x20.chr + 0x02.chr + 0x00.chr + 0x00.chr)  # Connection Accepted
delay(100)

puts "MQTT Subscribe"
packet = build_mqtt_subscribe_packet(topic: SUB_TOPIC)
System.exit "SUBACK failed" unless mqtt_request(packet, "+IPD,5:" + 0x90.chr + 0x03.chr + 0x00.chr + 0x01.chr + 0x00.chr)  # Success - Packet Identifier = 0x01, Maximum QoS = 0
delay(100)

puts "Topic - #{SUB_TOPIC}"

@lastmillis = millis()

one_sec_ticker = 0
led_state = 1

loop do
  now = millis()
  @lastmillis = now if (now - @lastmillis) < 0

  if (now - @lastmillis) > 1000
    @lastmillis = now

    one_sec_ticker += 1
    led(led_state)
    led_state = (1 - led_state)

    # PING
    if one_sec_ticker == MQTT_KEEP_ALIVE
      puts "MQTT PING"
      System.exit "PINGRESP failed" unless mqtt_request((0xc0.chr + 0x00.chr), "+IPD,2:" + 0xD0.chr + 0x00.chr)
      one_sec_ticker = 0
    end
  end

  # PUBLISH
  if digitalRead(BUTTON_PIN) == 0
    puts "MQTT PUBLISH"
    packet = build_mqtt_publish_packet(topic: PUB_TOPIC, message: "{ \"eventType\": \"test\", \"eventData\": { \"value\": \"#{now}\" } }")
    System.exit "PUBLISH failed" unless mqtt_request(packet, "SEND OK")
  end

  # Check Subscribe
  if @wifi.available() > 0
    receive_message = ""
    while @wifi.available() > 0
      receive_message += @wifi.read()
      delay 50    # a little hacky but this may be the best...
    end

    if receive_message.include?(SUB_TOPIC)
      puts "MQTT PUBACK"
      System.exit "PUBACK Fail" unless mqtt_request((0x40.chr + 0x02.chr), "SEND OK")

      # do something
      if receive_message.include?('switch":0')
        puts "switch: off"
        digitalWrite(LIGHT_LED, LOW)
      elsif receive_message.include?('switch":1')
        puts "switch: on"
        digitalWrite(LIGHT_LED, HIGH)
      end
    end
  end
end