multiple slave id

[heydan98]

I want to use esp32 read multiple Rs485 but i don't find way to set multiple slave id. Can you help me, please! This is my code: // Define an array of sensor addresses const uint8_t SENSOR_ADDRESSES[] = {0x01, 0x02, 0x03, 0x04, 0x06, 0x07, 0x08}; const int NUM_SENSORS = sizeof(SENSOR_ADDRESSES) / sizeof(SENSOR_ADDRESSES[0]);

// ... existing code ...

void setup() { // ... existing setup code ...

// Initialize ModbusMaster without specifying an address node.begin(0, Serial2); node.preTransmission(preTransmission); node.postTransmission(postTransmission);

// ... rest of setup code ... }

void loop() { // ... existing loop code ...

if (start_init == false && dataSent == true && (millis() - lastMsg >= 1000) && modeWifiSelect == "AWS") { // ... existing connection code ...

// Loop through each sensor address
for (int i = 0; i < NUM_SENSORS; i++) {
  uint8_t currentAddress = SENSOR_ADDRESSES[i];
  
  // Set the current sensor address
  node.setSlaveID(currentAddress);

  Serial.print("Reading sensor at address: 0x");
  Serial.println(currentAddress, HEX);

  // Perform read operation for the current sensor
  // You'll need to adjust the register addresses and data processing for each sensor type
  uint8_t result = node.readHoldingRegisters(0x0000, 4);

  if (result == node.ku8MBSuccess) {
    // Process and publish data for the current sensor
    processSensorData(currentAddress);
  } else {
    handleReadError(currentAddress, result);
  }

  // Add a small delay between sensor reads
  delay(100);
}

// ... rest of your loop code ...

}

// ... rest of your loop code ... }

void processSensorData(uint8_t sensorAddress) { // Process and publish data based on the sensor address switch (sensorAddress) { case 0x01: // O3 sensor processO3Data(); break; case 0x02: // NH4 sensor processNH4Data(); break; // Add cases for other sensor types default: Serial.println("Unknown sensor type"); } }

void processO3Data() { // Extract O3 value uint16_t O3_high = node.getResponseBuffer(2); uint16_t O3_low = node.getResponseBuffer(3);

uint32_t O3_combined = (uint32_t)O3_low << 16 | O3_high; float O3_value = ((float)&O3_combined);

String payload_O3 = "{"O3":" + String(O3_value, 2) + "}"; client.publish("v1/devices/me/telemetry", payload_O3.c_str()); }

void processNH4Data() { // Process NH4 data similarly to O3 // Adjust based on the actual data format of your NH4 sensor }

void handleReadError(uint8_t sensorAddress, uint8_t errorCode) { Serial.print("Failed to read from sensor at address 0x"); Serial.print(sensorAddress, HEX); Serial.print(". Error code: "); Serial.println(errorCode, HEX);

String sensorType = getSensorType(sensorAddress); String payload = "{"" + sensorType + "":NaN}"; client.publish("v1/devices/me/telemetry", payload.c_str()); }

String getSensorType(uint8_t sensorAddress) { switch (sensorAddress) { case 0x01: return "O3"; case 0x02: return "NH4"; case 0x03: return "NO3"; case 0x04: return "DO"; case 0x06: return "NO2"; case 0x07: return "Cl"; case 0x08: return "pH"; default: return "Unknown"; } }

// ... rest of your code ...