Boot Issues

Solutions for boot-related problems.

Board Doesn't Power On

Symptoms

• No power LED
• No serial output
• Board completely unresponsive

Solutions

1. Check Power Supply

   • Verify 5V output
   • Minimum 3A current
   • Try different power supply

2. Check Connections

   • Power jack polarity
   • Secure connection
   • No loose wires

3. Check for Shorts

   • Remove all peripherals
   • Inspect board for damage

Kernel Panic

Symptoms

• Boot starts but stops
• "Kernel panic" message
• Stack trace on serial console

Solutions

1. Re-image SD Card

   # Re-flash with balenaEtcher
   # or
   sudo dd if=image.wic of=/dev/sdX bs=4M

2. Check SD Card

   • Try different card
   • Check for errors:

   fsck -y /dev/sdX2

3. Verify Firmware

   • Re-flash SPI firmware
   • See Flashing Failures for recovery mode instructions

U-Boot Not Starting

Symptoms

• Serial shows garbage characters
• No "U-Boot" banner
• Prompt never appears

Solutions

1. Check DIP Switches

   • SW1.1 = OFF
   • SW1.2 = OFF (normal boot)

2. Check Serial Connection

   • Correct baud rate: 115200
   • Correct device path
   • Try different USB port

3. Re-flash Bootloader

   • Recovery mode flashing
   • See Flashing Failures for instructions

Filesystem Corruption

Symptoms

• "Read-only filesystem" errors
• I/O errors
• Boot hangs on filesystem check

Solutions

1. Run fsck

   # From another Linux system
   sudo fsck -y /dev/sdX2

2. Re-image SD Card

   • Backup data first
   • Flash fresh image

3. Proper Shutdown

   • Always use poweroff or reboot
   • Don't just unplug power

Boot Hangs

Symptoms

• Boot starts but stops mid-way
• No error message
• LED stuck in pattern

Solutions

1. Check Boot Files

   • /boot directory exists
   • Kernel image present
   • Device tree blob present

2. Verbose Boot

   • Interrupt U-Boot
   • Add debug to bootargs

3. Minimal Boot

   • Remove SD card
   • Boot from UART recovery

Quick Diagnostic Commands

# Check boot log
dmesg | head -100

# Check filesystem
df -h

# Check partitions
lsblk

# Check boot files
ls /boot

Still Having Issues?

• Flashing Failures
• Network Issues
• Contact support with serial log