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MQTT Client for mbed LPC1768 and Application Board over Ethernet; publish only.
Dependencies: C12832 MMA7660 MQTT
Fork of HelloMQTT by
Machine-to-Machine-Communication
Das Message Queue Telemetry Transport (MQTT) Protokoll ist ein effizientes Internet of Things (IoT) Protokoll mit wenig Protokolloverhead. Es wurde als lightweight publish/subscribe messaging transport entworfen. Es ist sinnvoll für Verbindungen mit Remote-Standorten, wo nur wenig Resourcen benötigt werden bzw. geringe Bandbreite zur Verfügung steht. Neben MQTT gibt es weitere IoT-Protokoll, wie HTTP, CoAP, XMPP, ... (Überischt über IoT Protokolle). Eine Beschreibung des MQTT ist z.B. hier zu finden.
MQTT implementiert das Publish/Subscribe-Pattern, daher wird ein Brocker für die Vermittlung der Nachrichten (topics) benötigt. Neben vielen quelloffenen Implementierungen (z. B. mosquitto) gibt es auch kommerzielle bzw. freie Server (Broker), die unterschiedliche Features bereit stellen (z. B. den in Deutschland entwickelten HiveMQ).
Für die Programmierung der Clients bzw. Ebedded Systems stehen ebenso sehr viele Libaries in verschiedenen Programmiersprachen zur Verfügung.
Weitere Kommunikationsmöglichkeiten
Diff: main.cpp
- Revision:
- 17:0811bdbdd78a
- Parent:
- 16:28d062c5522b
- Child:
- 18:07a79d8f01c3
--- a/main.cpp Mon Oct 06 11:42:25 2014 +0000 +++ b/main.cpp Mon Jul 27 09:16:08 2015 +0000 @@ -1,5 +1,5 @@ /******************************************************************************* - * Copyright (c) 2014 IBM Corp. + * Copyright (c) 2014, 2015 IBM Corp. * * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 @@ -12,6 +12,7 @@ * * Contributors: * Ian Craggs - initial API and implementation and/or initial documentation + * Ian Craggs - make sure QoS2 processing works, and add device headers *******************************************************************************/ /** @@ -24,9 +25,20 @@ */ +#include "C12832.h" -#include "C12832.h" -C12832 lcd(p5, p7, p6, p8, p11); +#if defined(TARGET_UBLOX_C027) +#warning "Compiling for mbed C027" +#include "C027.h" +#elif defined(TARGET_LPC1768) +#warning "Compiling for mbed LPC1768" +#include "LPC1768.h" +#elif defined(TARGET_K64F) +#warning "Compiling for mbed K64F" +#include "K64F.h" +#endif + +#define MQTTCLIENT_QOS2 1 #include "MQTTEthernet.h" #include "MQTTClient.h" @@ -37,11 +49,10 @@ void messageArrived(MQTT::MessageData& md) { MQTT::Message &message = md.message; - lcd.cls(); - lcd.locate(0,3); printf("Message arrived: qos %d, retained %d, dup %d, packetid %d\n", message.qos, message.retained, message.dup, message.id); printf("Payload %.*s\n", message.payloadlen, (char*)message.payload); ++arrivedcount; + lcd.cls(); lcd.puts((char*)message.payload); } @@ -49,20 +60,24 @@ int main(int argc, char* argv[]) { MQTTEthernet ipstack = MQTTEthernet(); - float version = 0.47; + float version = 0.5; char* topic = "mbed-sample"; - lcd.printf("Version is %f\n", version); - printf("Version is %f\n", version); + lcd.cls(); + lcd.printf("HelloMQTT: version is %f\n", version); MQTT::Client<MQTTEthernet, Countdown> client = MQTT::Client<MQTTEthernet, Countdown>(ipstack); char* hostname = "m2m.eclipse.org"; int port = 1883; + lcd.cls(); lcd.printf("Connecting to %s:%d\n", hostname, port); int rc = ipstack.connect(hostname, port); if (rc != 0) + { + lcd.cls(); lcd.printf("rc from TCP connect is %d\n", rc); + } MQTTPacket_connectData data = MQTTPacket_connectData_initializer; data.MQTTVersion = 3; @@ -70,10 +85,16 @@ data.username.cstring = "testuser"; data.password.cstring = "testpassword"; if ((rc = client.connect(data)) != 0) + { + lcd.cls(); lcd.printf("rc from MQTT connect is %d\n", rc); + } if ((rc = client.subscribe(topic, MQTT::QOS1, messageArrived)) != 0) + { + lcd.cls(); lcd.printf("rc from MQTT subscribe is %d\n", rc); + } MQTT::Message message; @@ -104,30 +125,23 @@ rc = client.publish(topic, message); while (arrivedcount < 3) client.yield(100); - - // n * QoS 2 - for (int i = 1; i <= 10; ++i) + + if ((rc = client.unsubscribe(topic)) != 0) { - sprintf(buf, "Hello World! QoS 2 message number %d from app version %f\n", i, version); - message.qos = MQTT::QOS2; - message.payloadlen = strlen(buf)+1; - rc = client.publish(topic, message); - while (arrivedcount < i + 3) - client.yield(100); + lcd.cls(); + lcd.printf("rc from unsubscribe was %d\n", rc); } - if ((rc = client.unsubscribe(topic)) != 0) - printf("rc from unsubscribe was %d\n", rc); - if ((rc = client.disconnect()) != 0) - printf("rc from disconnect was %d\n", rc); + { + lcd.cls(); + lcd.printf("rc from disconnect was %d\n", rc); + } ipstack.disconnect(); lcd.cls(); - lcd.locate(0,3); lcd.printf("Version %.2f: finish %d msgs\n", version, arrivedcount); - printf("Finishing with %d messages received\n", arrivedcount); return 0; }