Added mqtt status message for output pins; moved output init to beginning of setup

README.md

@@ -3,11 +3,34 @@
 Based on
 
 - Arduino Uno
-- Ethernet interface
+- Ethernet interface using MQTT
 
 Watchout for GPIO changes as triggers for
 
 - door bell input
-- post box observer (post entry)
+- mailbox observer (post entry)
-- post box observer (takeout posts)
+- mailbox observer (takeout posts)
-- ...
+- light requests (button)
+
+Serve outputs (using relays to trigger) for
+
+- turn light on at mailbox
+- turn bell sound on
+
+MQTT messages:
+
+- doorBellTopic = "doorBellGW/doorbell"
+  --> issued when pushbutton pressed: trigger / re-trigger / release
+- postboxFlapTopic = "doorBellGW/mailboxFlap"
+  --> issued, when flap is opened to enter mail: trigger / re-trigger / release
+- postboxDoorTopic = "doorBellGW/mailboxDoor"
+  --> issued, when mailbox door is opened to remove mail: trigger / re-trigger / release
+- doorBellTriggerSoundTopic = "doorBellGW/doorbellTrigger"
+  --> listens to this message and turns on relay for a short time to trigger the bell/gong
+- doorLightRequestTopic = "doorBellGW/lightRequest"
+  --> issued, when light pushbutton is pressed: trigger / re-trigger / release; light is turned on for 30 seconds
+- postboxLightTopic = "doorBellGW/light"
+  --> listens to this message and turns light on at mailbox for 30 seconds
+- postboxLightStatusTopic = "doorBellGW/light/status"
+  --> issued, when light at mailbox is turned on/off: on / off
+

src/main.cpp

@@ -44,8 +44,9 @@ const char *doorBellTopic = "doorBellGW/doorbell";
 const char *postboxFlapTopic = "doorBellGW/mailboxFlap";
 const char *postboxDoorTopic = "doorBellGW/mailboxDoor";
 const char *doorBellTriggerSoundTopic = "doorBellGW/doorbellTrigger";
-const char *postboxLightTopic = "doorBellGW/light";
 const char *doorLightRequestTopic = "doorBellGW/lightRequest";
+const char *postboxLightTopic = "doorBellGW/light";
+const char *postboxLightStatusTopic = "doorBellGW/light/status";
 
 EthernetClient ethClient;
 EthernetServer server(80);
@@ -66,7 +67,7 @@ struct {
   const unsigned long quietAfterTriggerFor_ms;
   unsigned long lastTrigger_ts;
   bool isTriggered;
-  const char *topic;
+  const char *topic; // sends changes: trigger / re-trigger, / release
   const uint8_t triggerOutputPin;
 } myInputs[] = {
   { DOOR_BELL_BUTTON_PIN, 500, 0 , false, doorBellTopic, DOOR_BELL_BUZZER_PIN },
@@ -83,9 +84,10 @@ struct {
   bool isTriggered;
   unsigned long lastTrigger_ts;
   const char *listenTopic; // can be triggered by mqtt message as well
+  const char *statusTopic; // sends on/off status
 } myOutputs[] = {
-  { DOOR_BELL_BUZZER_PIN, 500, false, 0, doorBellTriggerSoundTopic},
+  { DOOR_BELL_BUZZER_PIN, 500, false, 0, doorBellTriggerSoundTopic, NULL },
-  { POSTBOX_LIGHT_PIN, 30000, false, 0, postboxLightTopic}
+  { POSTBOX_LIGHT_PIN, 30000, false, 0, postboxLightTopic, postboxLightStatusTopic }
 };
 #define NUM_OUTPUTS (sizeof(myOutputs) / sizeof(myOutputs[0]))
 
@@ -109,6 +111,13 @@ void switchOutputOn(unsigned int outputNumber) {
   digitalWrite(myOutputs[outputNumber].pin, LOW);
   myOutputs[outputNumber].isTriggered = true;
   myOutputs[outputNumber].lastTrigger_ts = millis();
+  if (myOutputs[outputNumber].statusTopic != NULL) {
+    sendMqttMessage(myOutputs[outputNumber].statusTopic, "on");
+  }
+}
+
+void switchOutputOffHWOnly(unsigned int outputNumber) {
+  digitalWrite(myOutputs[outputNumber].pin, HIGH);
 }
 
 void switchOutputOff(unsigned int outputNumber) {
@@ -118,8 +127,11 @@ void switchOutputOff(unsigned int outputNumber) {
   Serial.print(myOutputs[outputNumber].pin);
   Serial.print(F(") topic "));
   Serial.println(myOutputs[outputNumber].listenTopic);
-  digitalWrite(myOutputs[outputNumber].pin, HIGH);
+  switchOutputOffHWOnly(outputNumber);
   myOutputs[outputNumber].isTriggered = false;
+  if (myOutputs[outputNumber].statusTopic != NULL) {
+    sendMqttMessage(myOutputs[outputNumber].statusTopic, "off");
+  }
 }
 
 void checkOutputAutoOff() {
@@ -209,7 +221,7 @@ void reconnect() {
 
 void sendMqttMessage(const char *topic, const char *message) {
   reconnect();
-  mqttClient.publish(topic, message);
+  mqttClient.publish_P(topic, message, true);
 }
 
 void setup()
@@ -220,6 +232,20 @@ void setup()
   Serial.println(F("DoorbellGW Copyright (C) 2020 Dirk Jahnke"));
   Serial.println(F("Door Bell MQTT Gateway started."));
 
+  // setup the input and output pins
+  for (unsigned int i = 0; i < NUM_INPUTS; i++) {
+    pinMode(myInputs[i].pin, INPUT_PULLUP);
+  }
+
+  // Setup the output pins :
+  for (unsigned int i=0; i < NUM_OUTPUTS; ++i) {
+    pinMode(myOutputs[i].pin, OUTPUT);
+    switchOutputOffHWOnly(i);
+  }
+  pinMode(LED_PIN, OUTPUT);
+  digitalWrite(LED_PIN, ledState);
+
+  // setup MQTT
   mqttClient.setServer(mqttServerIP, 1883);
   mqttClient.setCallback(mqttReceiveMessage);
 
@@ -235,18 +261,10 @@ void setup()
   Serial.print(F("Please connect to http://"));
   Serial.println(Ethernet.localIP());
 
-  // setup the input and output pins
+  // Setup the output pins logically:
-  for (unsigned int i = 0; i < NUM_INPUTS; i++) {
-    pinMode(myInputs[i].pin, INPUT_PULLUP);
-  }
-
-  // Setup the output pins :
   for (unsigned int i=0; i < NUM_OUTPUTS; ++i) {
-    pinMode(myOutputs[i].pin, OUTPUT);
     switchOutputOff(i);
   }
-  pinMode(LED_PIN, OUTPUT);
-  digitalWrite(LED_PIN, ledState);
 }