Diff: main.cpp

Revision:

8:7b4e0d15249f

Parent:

7:4435b52322e4

Child:

9:18b414a8c5f7

--- a/main.cpp	Sun Nov 29 14:39:02 2015 +0000
+++ b/main.cpp	Sun Nov 29 18:18:46 2015 +0000
@@ -1,16 +1,14 @@
-// In this example an MQTT client is created.
-// It is publishing a simple 'example/hello' message with payload 'Hello World.'
-// and subscribes to some messages assumably published by other client(s).
-// Ethernet connection is assured by an ENC28J60 Ehernet module.
+// In this example we create an MQTT client.
+// It's publishing messages with topic 'example/hello' and 'Hello World!' payload.
+// The MQTT client also subscribes to some topics which are in its interest to receive.
+// Ethernet connection is assured by an affordable ENC28J60 Ethernet module.
 #include "mbed.h"
 #include <UIPEthernet.h>
 #include <UIPClient.h>
 #include <MQTTClient.h>
 #include <string>
 
-using namespace     std;
-
-Serial              pc(USBTX, USBRX);
+Serial  pc(USBTX, USBRX);
 
 #define DHCP    1   // comment out this line if you'd like to use static IP address
 
@@ -39,8 +37,7 @@
 const IPAddress MY_IP(192, 168, 1, 181);
 #endif
 
-const int           INTERVAL = 5;    // Interval for publishing the messages (in seconds)
-
+const int           INTERVAL = 10;    // Interval for publishing the messages (in seconds)
 char                message_buff[100];
 
 // MQTT broker is like a post office.
@@ -48,7 +45,7 @@
 // So the 'example/hello' messages published by this client will be sent to the broker.
 // Then the broker will send them to all clients which subscribed to such topic (example/hello).
 // Also this client will receive all messages with topics it subscribed to.
-// 'Mosquitto' is a free implementation of MQTT broker for Linux machines (e.g. Raspberry Pi, Ubuntu etc.)
+// 'Mosquitto' is a free implementation of MQTT broker for Linux (e.g. Raspberry Pi, Ubuntu etc.)
 IPAddress           serverIP(192, 168, 1, 30);  // IP address of your MQTT broker (adapt)
 EthernetClient      ethernetClient;
 void                onMqttMessage(char* topic, uint8_t* payload, unsigned int length);
@@ -62,18 +59,20 @@
  */
 
 int main(void) {
-    const int   MAX_COUNT = 5;
-    int         i = 0;
-    bool        connected = false;
-    char*       payload = "Hello World.";
-    time_t      t = 0;
-    time_t      lastTime = t;
+    const int           MAX_TRIES = 5;
+    const unsigned long INTERVAL = 5;
+    int                 i = 0;
+    bool                connected = false;
+    char*               payload = "Hello World!";
+    unsigned long       t = 0;
+    unsigned long       lastTime = t;
+
 
     // initialize the ethernet device
 
 #if defined(DHCP)
     pc.printf("Searching for DHCP server..\r\n");
- 
+
     if(UIPEthernet.begin(MY_MAC) != 1) {
         pc.printf("No DHCP server found.\r\n");
         pc.printf("Exiting application.\r\n");
@@ -88,22 +87,22 @@
 #else
     UIPEthernet.begin(MY_MAC, MY_IP);
 #endif
-    
+
     pc.printf("Connecting to MQTT broker ..\r\n");
     do
     {
         wait(1.0);
         connected = mqttClient.connect("myMQTTHelloClient");
-    } while(!connected && (i < MAX_COUNT));
+    } while(!connected && (i++ < MAX_TRIES));
 
     if(connected) {
         pc.printf("MQTT broker connected.\r\n");
-        // The client can subscribe to as many topics as you like.
-        mqttClient.subscribe("outdoor/temperature"); 
-        mqttClient.subscribe("boiler/outlet/temperature");
+        // The client can subscribe to many topics.
         pc.printf("Subscribing to topics:\r\n");
         pc.printf("    outdoor/temperature\r\n");
         pc.printf("    boiler/outlet/temperature\r\n");
+        mqttClient.subscribe("outdoor/temperature");
+        mqttClient.subscribe("boiler/outlet/temperature");
     }
     else {
         pc.printf("Failed to connect to MQTT broker.\r\n");
@@ -114,8 +113,8 @@
         if(t > (lastTime + INTERVAL)) {
             lastTime = t;
             if(connected) {
+                pc.printf("Publishing: example/hello\r\n");
                 mqttClient.publish("example/hello", payload);
-                pc.printf("Publishing: example/hello\r\n");
             }
         }
         mqttClient.loop();  // MQTT client loop processing (receiving messages)
@@ -124,7 +123,7 @@
 
 /**
  * @brief   Called on new MQTT message arrival
- * @note    
+ * @note
  * @param   topic:      The topic of the new message
  *          payload:    The payload of the new message
  *          length:     Payload's length
@@ -143,5 +142,5 @@
     }
 
     message_buff[i] = '\0';
-    pc.printf("    Payload: %s\r\n", message_buff);
+    pc.printf("  Payload: %s\r\n", message_buff);
 }