Troubleshooting
Troubleshooting common issues with your ATmega32 project (Arduino IDE).
This guide escalates from basic hiccups to trickier stuff.
1. Start With the Basics
Board Not Detected on Upload
- Make sure your USB-to-Serial converter (e.g., CH340, FTDI) is properly connected.
- Double-check TX/RX wiring, they must be crossed (TX → RX, RX → TX).
- Use the correct COM port in Arduino IDE.
- Select "ATmega32 (external 16MHz)" if you're using a crystal oscillator.
- Try pressing reset right before clicking upload (timing matters!).
2. Compilation or Upload Errors
“avrdude: stk500_recv(): programmer not responding”
- Check if bootloader is properly burned.
- Use "Burn Bootloader" via another AVR (Arduino as ISP) before uploading code.
- If you're using a bare chip (no bootloader), upload using ISP, not Serial.
3. Code Runs, But No Output
No Serial Output on Monitor
- Ensure
Serial.begin(19200);
is set insetup()
, baud rate must match your terminal. - Double-check TX (usually PD1) is correctly connected to USB-TTL adapter’s RX.
- Use a terminal emulator like PuTTY, set to 19200 baud, 8 data bits, no parity, 1 stop bit (8N1).
- Check if serial pins are inverted or if level shifting is needed (5V to 3.3V logic issue).
- Avoid using the same pin for multiple functions, UART should be isolated during debugging.
No Power or Reset Behavior
- Power supply must be regulated and stable (recommended: 5V @ 500mA+).
- If using USB-TTL, ensure the VCC is not overloaded, add external power if needed.
- Check for loose breadboard wires, damaged jumper cables, or dry solder joints.
4. I/O Not Behaving As Expected
Digital Inputs Always HIGH or LOW
- Floating pins! Add pull-up or pull-down resistors (or use
INPUT_PULLUP
). - Avoid connecting buttons directly to VCC/GND without resistance.
5. SD Card, Sensors, or Peripherals Failing
SD Card Not Detected
- Use software SPI if hardware SPI conflicts with other devices.
- Lower SPI speed (
SD.begin(CS, SPI_SPEED_SLOW)
). - Check if your SD card module uses level shifting (not direct 5V).
Sensor Reads 0 or -1
- Use I2C scanner to confirm device is detected.
- Watch out for address mismatches.
- Use external pull-up resistors if I2C is noisy or unreliable.
6. Stability & Power Problems
Random Resets or Glitches
- Bad power supply? Try using a stable 5V adapter or LDO.
- Add decoupling caps near power pins (100nF typical).
- Check for brown-out reset issues (
fuses
might need adjusting).
Chip Heating Up
- Double-check your wiring, especially VCC-GND short or incorrect polarity.
- Some modules draw too much current, use heat sinks or proper regulators.
7. Still Broken?
Open a GitHub issue, send over your schematic, and describe what’s going wrong:
Submit an Issue
No worries — even pros get stuck sometimes. We're all in this silicon struggle together