Hardware Troubleshooting

Power Management and Brownouts

If the Snake V1 experiences unexpected reboots, freezing, or "brownout" conditions (where the voltage drops below the operational threshold), it is typically due to power supply instability during high-draw operations like Sub-GHz transmission or microSD card writes.

Symptom: Device Reboots During Wireless Transmission

The STM32WB35 and the CC1101 transceiver require stable current during radio bursts.

• Check USB Cable Quality: Use a high-quality, shielded USB-C cable. Low-quality cables often have significant voltage drops that cannot sustain the Snake V1 during peak power draws.
• Power Source: If powering from a computer's USB port, ensure the port is capable of providing at least 500mA. Avoid unpowered USB hubs.

Symptom: MicroSD Card Read/Write Failures

• Current Spikes: Writing to a microSD card can cause momentary current spikes. If the device crashes specifically when saving logs or data, ensure your power source is stable.
• Physical Connection: Inspect the Molex 47352-1001 connector for debris. Ensure the card is fully seated; a loose connection can cause high-frequency noise on the SPI bus.

Signal Interference

Because the Snake V1 operates across multiple frequencies (Sub-GHz, BLE, NFC, IR), signal integrity and environmental interference are common troubleshooting points.

Sub-GHz (CC1101) Connectivity Issues

• Antenna Proximity: Ensure the Tapered Helical Antenna is not bent or touching other metallic components or the PCB ground plane. Physical contact with the antenna can severely detune the frequency.
• Frequency Mismatch: If you are unable to receive signals, verify that your center frequency matches the target device. The CC1101 is highly sensitive to frequency offsets.
• Environmental Noise: Industrial equipment or high-density wireless environments can saturate the CC1101. Try testing in an RF-quiet area to rule out external interference.

Infrared (IR) Failures

• Ambient Light: The TSOP38238 receiver is designed to filter noise, but direct sunlight or powerful halogen lamps can saturate the sensor, preventing it from detecting the TSAL6400 transmitter's pulses.
• Line of Sight: IR is a line-of-sight technology. Ensure there is no physical obstruction between the transmitter/receiver and the target device.

Connectivity and Peripheral Troubleshooting

USB-C Interface

The Snake V1 uses a GCT USB4135-GF-A connector for both power and data.

• Device Not Recognized: If the STM32 is not appearing as a COM port or HID device on your host machine, check the USB-C orientation. While USB-C is reversible, some low-cost cables are wired incorrectly.
• Data vs. Power: Ensure you are using a Data-sync cable. Many "charging" cables lack the D+/D- lines required for communication with the STM32WB.

MicroSD Compatibility

If the system fails to mount the filesystem:

• Format: Ensure the microSD card is formatted to FAT32. Large-capacity cards (SDXC) formatted to exFAT may not be supported depending on your firmware configuration.
• Speed Class: Use a Class 10 or UHS-1 card for best results. Slower cards may cause timing timeouts during the SPI initialization phase.

Debugging via Serial

If the hardware is unresponsive, connect to the device via a serial terminal (e.g., PuTTY, Tera Term, or screen) to check for error logs.

# Example for Linux users to monitor serial output
screen /dev/ttyACM0 115200

Typical error codes to look for in the console:

• ERR_SD_MOUNT: Check card formatting and seating.
• ERR_CC1101_INIT: Check Sub-GHz SPI wiring and antenna.
• ERR_BROWN_OUT: Power supply is insufficient.