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Testing Procedures

Verify your complete IoT Toolkit setup.

Test Checklist

Hardware Tests

  • ESP32 powers on
  • All sensors detected via I2C
  • LCD display works
  • TFT display works (if connected)
  • WiFi connects successfully
  • MQTT connects successfully

Software Tests

  • Code compiles without errors
  • Code uploads successfully
  • Serial Monitor shows data
  • Sensors read correctly
  • Display updates correctly
  • MQTT publishes successfully

Step-by-Step Testing

Phase 1: Hardware Verification

1.1 Power Test

  1. Connect ESP32 via USB
  2. Check power LED lights up
  3. Open Serial Monitor (115200 baud)
  4. Verify boot messages appear

Expected output: 

rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
...
WiFi connected
IP address: 192.168.1.xxx

1.2 I2C Scanner Test

Upload I2C scanner sketch:

#include <Wire.h>

void setup() {
  Wire.begin();
  Serial.begin(115200);
  Serial.println("I2C Scanner");
}

void loop() {
  Serial.println("Scanning...");
  for (byte i = 1; i < 127; i++) {
    Wire.beginTransmission(i);
    if (Wire.endTransmission() == 0) {
      Serial.print("Found: 0x");
      Serial.println(i, HEX);
    }
  }
  Serial.println("Done\n");
  delay(5000);
}

Verify all sensors are detected.

1.3 Individual Sensor Tests

Test each sensor with standalone sketch from code examples.

Sensor Expected Result
Temperature Reading in °C, varies with environment
Humidity Reading in %, varies with environment
Vibration Changes when sensor is moved
Acoustic Changes when sound is made

1.4 Display Tests

LCD Test: - Text appears on display - Backlight works - Text updates

TFT Test: - Screen initializes - Colors display correctly - Graphics render

Phase 2: Integration Test

2.1 Upload Complete Code

Upload the complete integration code.

2.2 Serial Monitor Check

Look for these messages:

========================================
IoT Toolkit - Complete Integration
========================================

I2C initialized
WiFi connected!
IP: 192.168.1.xxx
MQTT connected
Setup complete. Starting main loop...

Reading sensors...
Temp: 25.5C, Hum: 60%, Vib: 45, Acoustic: 72dB
Sending MQTT: {"device_id":"iot-toolkit-001",...}
MQTT publish successful

2.3 LCD Display Check

Display should cycle through: 1. Temperature and Humidity 2. Vibration and Acoustic 3. WiFi RSSI and Read Count

Phase 3: Cloud Test

3.1 MQTT Test

Using mosquitto_sub
mosquitto_sub -h broker.hivemq.com -t "iot-toolkit/#" -v

Expected output: 

iot-toolkit/data {"device_id":"iot-toolkit-001","timestamp":12345,"sensors":{"temperature":25.5,...}}

Using MQTT.fx or similar GUI tool
  1. Connect to broker.hivemq.com:1883
  2. Subscribe to topic: iot-toolkit/#
  3. Verify messages appear every 10 seconds

3.2 HTTP Test (if using HTTP)

curl -X POST http://your-server/api/data \
  -H "Content-Type: application/json" \
  -d '{"temperature": 25.5, "humidity": 60.0}'

Phase 4: Long-Term Test

4.1 Stability Test

Run system for 24 hours and verify: - No crashes - Consistent data transmission - No memory leaks (free heap stable)

4.2 Reconnection Test

  1. Turn off WiFi router
  2. Wait 1 minute
  3. Turn on WiFi router
  4. Verify ESP32 reconnects automatically

Common Issues

No I2C Devices Found

Symptoms: I2C scanner shows no devices

Solutions: - Check wiring (SDA to GPIO21, SCL to GPIO22) - Verify 3.3V power - Check for bent pins on breadboard - Add 4.7kΩ pull-up resistors

WiFi Won't Connect

Symptoms: Serial shows connection failed

Solutions: - Verify WiFi credentials - Check 2.4GHz network (not 5GHz) - Move closer to router - Check if MAC filtering is enabled

MQTT Connection Fails

Symptoms: MQTT connect returns error code

Solutions: - Check broker address and port - Verify firewall allows outbound connections - Try different broker (test with hivemq) - Check client ID is unique

Sensor Readings Wrong

Symptoms: Impossible values (negative, zero, max)

Solutions: - Verify sensor initialization - Check I2C address - Verify sensor is powered - Check library compatibility

Debug Mode

Enable verbose logging:

#define DEBUG_MODE true

#if DEBUG_MODE
  #define DEBUG_PRINT(x) Serial.print(x)
  #define DEBUG_PRINTLN(x) Serial.println(x)
#else
  #define DEBUG_PRINT(x)
  #define DEBUG_PRINTLN(x)
#endif

Test Report Template

IoT Toolkit Test Report
Date: ___________
Tested by: ___________

Hardware Status:
[ ] ESP32 DevKit V1
[ ] Temperature sensor detected at 0x__
[ ] Humidity sensor detected at 0x__
[ ] Vibration sensor detected at 0x__
[ ] Acoustic sensor detected at 0x__
[ ] LCD Display working
[ ] TFT Display working (optional)

Software Status:
[ ] Code compiles
[ ] Code uploads
[ ] WiFi connects
[ ] MQTT connects
[ ] Sensors read data
[ ] LCD updates
[ ] MQTT publishes

Cloud Status:
[ ] MQTT messages received
[ ] Data format correct
[ ] Timestamp accurate

Notes:
_________________________________
_________________________________
_________________________________

Signature: ___________

Next Steps

After passing all tests:

  1. Deploy to permanent location
  2. Configure cloud services
  3. Set up monitoring dashboard
  4. Review troubleshooting guide

Getting Help

If tests fail:

  1. Check Troubleshooting
  2. Verify wiring against diagrams
  3. Test with minimal code (individual components)
  4. Check Serial Monitor for error messages