Why STM32F103 RDT6 Crashes After Power -On and How to Fix It

Why STM32F103RDT6 Crashes After Power-On and How to Fix It

If you’re encountering issues where your STM32F103RDT6 microcontroller crashes right after power-on, there could be a few key causes behind this. In this guide, we'll break down the possible reasons for this crash and provide a step-by-step approach to fixing the issue.

1. Power Supply Issues

The first place to check is the power supply. The STM32F103RDT6 may fail to start properly if it doesn't receive a stable, clean voltage during power-on. An unstable or noisy power supply can cause the MCU to crash right after power-on.

Possible Causes:

Voltage spikes or dips Insufficient or unstable power supply (e.g., unregulated power) Power rail not reaching proper levels (usually 3.3V or 5V depending on your configuration)

Solution:

Use a stable regulated power supply. Add decoupling capacitor s (e.g., 100nF and 10uF) close to the power pins of the STM32F103RDT6 to filter out noise. If the power supply is shared with other components, ensure that it can handle the required load without voltage dips. 2. Watchdog Timer Not Being Reset

Another common issue is that the Watchdog Timer (WDT) is enabled, and it is not being properly reset in your application. This results in the microcontroller continuously resetting itself.

Possible Causes:

The watchdog timer is configured and enabled, but your code doesn’t reset it periodically. The WDT timeout is set too short, causing a reset even if the program hasn’t completed its tasks.

Solution:

If you’re using a watchdog timer, make sure you reset it periodically in your code. Alternatively, disable the watchdog timer if you don't need it for your application. Check the WDT timeout value and adjust it to a more appropriate length, giving the microcontroller enough time to perform its tasks. 3. Bootloader or Firmware Corruption

If the firmware is corrupted or the bootloader is not functioning properly, the STM32F103RDT6 may crash after power-on. This could happen if there’s an issue during flashing or if the firmware has errors that prevent it from executing properly.

Possible Causes:

Corrupted firmware or bootloader Incomplete flashing of the microcontroller Incorrect programming settings

Solution:

Reflash the firmware using a reliable programmer/debugger (like ST-Link or J-Link). Ensure you are using the correct bootloader version and that it is functioning properly. If needed, re-burn the bootloader using an external programmer if you suspect it has become corrupted. 4. Clock Configuration Issues

Improper clock configuration can cause the STM32F103RDT6 to fail at startup. If the clock source or frequency is not set correctly, the MCU might enter an invalid state.

Possible Causes:

The PLL (Phase-Locked Loop) is misconfigured, leading to an unstable clock source. The microcontroller fails to lock the clock properly after power-on.

Solution:

Check the clock configuration in your code, particularly the settings related to the PLL and the HSE (High-Speed External) oscillator. Ensure that the clock settings are correct and that the STM32F103RDT6 is using the intended clock source. You can use the STM32CubeMX tool to generate correct initialization code for your clock configuration. 5. Faulty External Components

External components like sensors, communication peripherals, or memory module s connected to the STM32F103RDT6 could also be causing the crash. A malfunctioning peripheral may draw too much current, produce a short circuit, or send faulty signals to the microcontroller, causing it to crash.

Possible Causes:

Short circuits or power spikes caused by external components Improper initialization of external peripherals or sensors Incompatible voltage levels between external components and the STM32F103RDT6

Solution:

Disconnect all external components and check if the MCU still crashes after power-on. If it doesn’t crash without peripherals, reconnect them one at a time to identify the faulty component. Ensure that all external devices are properly powered and initialized. Use level shifters or voltage regulators if external components require different voltage levels. 6. Reset Pin or External Reset Circuit Malfunction

The reset pin is crucial for the proper startup of the STM32F103RDT6. If there’s a fault in the reset circuitry or the reset pin is left floating, the MCU may not reset correctly or could enter an unpredictable state.

Possible Causes:

The reset pin is floating or being driven incorrectly. The external reset circuitry is malfunctioning.

Solution:

Make sure the reset pin is connected to a proper external reset circuit (usually with a pull-up resistor). Verify the external reset circuit design and ensure that the STM32F103RDT6 is being properly reset at power-on. If using an external reset IC, check its functionality.

Summary of Solutions:

Check Power Supply: Ensure stable voltage and add decoupling capacitors. Verify Watchdog Timer: Reset the watchdog periodically or disable it. Reflash Firmware: Reburn the firmware and check the bootloader. Fix Clock Configuration: Ensure correct clock settings using STM32CubeMX. Inspect External Components: Disconnect peripherals and reconnect them one by one. Check Reset Circuit: Ensure the reset pin and external reset circuit are working correctly.

By systematically checking each of these potential causes and applying the corresponding solutions, you should be able to resolve the issue of your STM32F103RDT6 crashing after power-on. If the problem persists, double-check each step or consider testing with a different STM32F103RDT6 chip to rule out hardware defects.