mongoose/examples/arduino/w5500-mqtt/w5500-mqtt.ino
2023-07-21 16:45:14 -03:00

105 lines
3.4 KiB
C++

#include <SPI.h>
#include "mongoose.h"
#define MQTT_SERVER "mqtt://broker.hivemq.com:1883"
struct mg_connection *mqtt_connection;
const char *mqtt_subscribe_topic = "mg/rx";
const char *mqtt_publish_topic = "mg/tx";
#define SS_PIN 17 // Slave select pin
struct mg_mgr mgr; // Mongoose event manager
struct mg_tcpip_spi spi = {
NULL, // SPI data
[](void *) { digitalWrite(SS_PIN, LOW); }, // Begin transaction
[](void *) { digitalWrite(SS_PIN, HIGH); }, // End transaction
[](void *, uint8_t c) { return SPI.transfer(c); }, // Execute transaction
};
struct mg_tcpip_if mif = {.mac = {2, 0, 1, 2, 3, 5}}; // network interface
static void mqtt_publish(const char *message) {
struct mg_mqtt_opts opts = {};
opts.topic = mg_str(mqtt_publish_topic);
opts.message = mg_str(message);
if (mqtt_connection) mg_mqtt_pub(mqtt_connection, &opts);
}
static void exec_command(const char *req, size_t req_len) {
char res[100];
if (req_len == 2 && strncmp(req, "on", req_len) == 0) {
digitalWrite(LED_BUILTIN, true);
snprintf(res, sizeof(res), "LED on");
} else if (req_len == 3 && strncmp(req, "off", req_len) == 0) {
digitalWrite(LED_BUILTIN, false);
snprintf(res, sizeof(res), "LED off");
} else {
snprintf(res, sizeof(res), "Unknown command: [%.*s]", (int) req_len, req);
}
Serial.println(res);
mqtt_publish(res);
}
static void process_input(char c) {
static char buf[100];
static size_t len = 0;
char response[100];
if (c != '\n' && c != '\0') buf[len++] = c; // Append to the buffer
if (len >= sizeof(buf)) len = 0; // On overflow, reset
if (c == '\n' && len > 0) {
exec_command(buf, len);
len = 0;
}
}
static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
if (ev == MG_EV_MQTT_OPEN) {
MG_INFO(("%lu CONNECTED to %s", c->id, MQTT_SERVER));
struct mg_mqtt_opts opts = {};
opts.topic = mg_str(mqtt_subscribe_topic);
mg_mqtt_sub(c, &opts);
MG_INFO(("%lu SUBSCRIBED to %s", c->id, mqtt_subscribe_topic));
} else if (ev == MG_EV_MQTT_MSG) {
// Received MQTT message
struct mg_mqtt_message *mm = (struct mg_mqtt_message *) ev_data;
MG_INFO(("%lu RECEIVED %.*s <- %.*s", c->id, (int) mm->data.len,
mm->data.ptr, (int) mm->topic.len, mm->topic.ptr));
exec_command(mm->data.ptr, mm->data.len);
} else if (ev == MG_EV_CLOSE) {
MG_INFO(("%lu CLOSED", c->id));
mqtt_connection = NULL;
}
}
static void timer_fn(void *arg) {
struct mg_mgr *mgr = (struct mg_mgr *) arg;
struct mg_mqtt_opts opts;
memset(&opts, 0, sizeof(opts));
opts.clean = true;
if (mif.state == MG_TCPIP_STATE_READY && mqtt_connection == NULL) {
mqtt_connection = mg_mqtt_connect(mgr, MQTT_SERVER, &opts, fn, NULL);
}
MG_INFO(("Eth: %d, MQTT: %p", mif.state, mqtt_connection));
}
void setup() {
Serial.begin(115200);
SPI.begin();
pinMode(SS_PIN, OUTPUT);
pinMode(LED_BUILTIN, OUTPUT);
// Set Mongoose logging function to a serial print
mg_log_set_fn([](char ch, void *) { Serial.print(ch); }, NULL);
mg_mgr_init(&mgr);
mif.driver = &mg_tcpip_driver_w5500;
mif.driver_data = &spi;
mg_tcpip_init(&mgr, &mif);
// Start a timer that keeps MQTT connection alive
mg_timer_add(&mgr, 3000, MG_TIMER_REPEAT, timer_fn, &mgr);
}
void loop() {
if (Serial.available()) process_input(Serial.read());
mg_mgr_poll(&mgr, 1);
}