Troubleshooting Guide¶

Note

This section provides diagnostic procedures and solutions for common KISS Fuzzer operational issues.

Device Boot Problems¶

Complete System Failure¶

Symptoms: No display output, no LED activity, device appears non-functional

Diagnostic Steps:

Power System Verification:

Verify USB-C cable is fully seated and data-capable
Test with multiple power sources (wall adapter, computer USB port)
Check for any visible damage to USB-C connector

Battery Assessment:

Allow device to charge for minimum 30 minutes before testing
If available, measure battery voltage (should be above 3.0V)
Consider battery replacement if voltage is consistently low

Firmware Recovery:

Enter recovery mode by holding BOOTSEL button during USB connection
Device should appear as USB mass storage device
Flash latest firmware UF2 file to restore operation

Partial Boot Failure¶

Symptoms: Some systems initialize but device does not reach operational state

Common Causes:

Corrupted configuration data
Hardware subsystem failure
Incomplete firmware installation

Resolution Steps:

Perform factory reset through recovery mode
Verify all hardware connections are secure
Reflash firmware with verified UF2 file

JTAG Interface Issues¶

Device Detection Failure¶

Symptoms: Scan operations report “No devices found”

Systematic Diagnosis:

Physical Connection Verification:

Confirm all signal wires are properly connected
Verify ground connection is established first
Check target device power status
Ensure voltage level compatibility (1.8V, 3.3V, 5V)

Signal Integrity Checks:

Test connections with multimeter for continuity
Verify signal voltage levels match target requirements
Check for proper impedance on clock signals

Protocol Configuration:

Attempt SWD mode if JTAG detection fails
Reduce clock frequency for marginal connections
Verify target device supports selected debug protocol
- Double-check target device pinout
- Use oscilloscope to verify signal integrity
- Check for proper voltage levels

Power Issues
- Ensure target device is powered
- Check VCC voltage matches target requirements
- Verify ground connections
Clock Frequency
- Reduce JTAG frequency to 1 kHz
- Some devices require slower clocking
- Try different frequency settings

JTAG Chain Errors¶

Symptom: "Chain integrity check failed"

Solutions:

Chain Configuration
- Verify device count in chain
- Check for proper daisy-chaining
- Ensure all devices powered
Signal Quality
- Check cable length (keep < 30cm)
- Add pull-up resistors if needed
- Verify signal rise/fall times

Inconsistent Scan Results¶

Intermittent Detection¶

Symptom: Devices detected sometimes, not others

Solutions:

Connection Quality
- Clean connector contacts
- Check for loose connections
- Use proper probe clips
EMI Issues
- Keep away from interference sources
- Use shielded cables
- Add ferrite cores if needed

Display Problems¶

Blank/Corrupted Display¶

No Display Output¶

Symptom: OLED remains black

Solutions:

I2C Communication
- Check SDA/SCL connections
- Verify I2C address (0x3C)
- Test with I2C scanner
Power Supply
- Verify 3.3V supply to display
- Check current consumption
- Test display independently

Garbled Text¶

Symptom: Random pixels or corrupted characters

Solutions:

Signal Integrity
- Check I2C signal quality
- Reduce clock frequency
- Add pull-up resistors
Software Issues
- Update display driver
- Check frame buffer integrity
- Verify font data

Wi-Fi Connectivity Issues¶

Cannot Connect to Access Point¶

Network Not Visible¶

Symptom: KISS-Fuzzer network doesn't appear

Solutions:

Wi-Fi Module
- Restart device
- Check Wi-Fi status LEDs
- Factory reset Wi-Fi settings
Channel Conflicts
- Change Wi-Fi channel in settings
- Scan for available channels
- Avoid crowded frequencies

Connection Drops¶

Symptom: Frequent disconnections

Solutions:

Range Issues
- Move closer to device
- Check antenna connections
- Remove interference sources
Power Management
- Disable Wi-Fi power saving
- Check battery level
- Ensure stable power supply

Web Interface Problems¶

Page Won’t Load¶

Symptom: Browser shows connection error

Solutions:

Network Configuration
- Verify IP address (192.168.4.1)
- Check DHCP assignment
- Try direct IP access
Browser Issues
- Clear browser cache
- Try different browser
- Disable browser extensions

Storage Issues¶

SD Card Not Recognized¶

Card Detection Failure¶

Symptom: "SD card not found" error

Solutions:

Physical Issues
- Ensure card fully inserted
- Clean card contacts
- Try different SD card
Format Problems
- Format card as FAT32
- Use 32GB or smaller card
- Check for bad sectors

File System Errors¶

Symptom: Cannot read/write files

Solutions:

File System Corruption
- Run chkdsk/fsck on card
- Reformat if necessary
- Use high-quality SD card
Write Protection
- Check write-protect switch
- Verify file permissions
- Test with different files

Power Management Issues¶

Poor Battery Life¶

Rapid Discharge¶

Symptom: Battery drains quickly

Solutions:

Power Settings
- Reduce display brightness
- Enable power saving mode
- Disable unused features
Battery Health
- Check battery voltage curve
- Replace aged battery
- Calibrate battery meter

Charging Problems¶

Symptom: Battery won't charge or charges slowly

Solutions:

Charger Issues
- Use proper USB-C charger
- Check cable for damage
- Verify charging current
Thermal Issues
- Ensure proper ventilation
- Check for overheating
- Allow device to cool

Performance Issues¶

Slow Operation¶

UI Responsiveness¶

Symptom: Laggy menu navigation

Solutions:

System Load
- Close unnecessary tasks
- Check memory usage
- Restart device
SD Card Speed
- Use Class 10 or better card
- Defragment if possible
- Check for card errors

JTAG Speed Issues¶

Symptom: Slow scanning/dumping

Solutions:

Frequency Settings
- Increase JTAG frequency
- Check target capabilities
- Monitor signal quality
Buffer Settings
- Increase buffer sizes
- Optimize memory allocation
- Use DMA for transfers

Error Code Reference¶

System Error Codes¶

Code	Description	Solution
E001	Hardware initialization failed	Check hardware connections
E002	Memory allocation error	Restart device, check memory
E003	SD card error	Check/replace SD card
E004	Wi-Fi initialization failed	Reset Wi-Fi settings
E005	JTAG timeout	Check target connections

JTAG Error Codes¶

Code	Description	Solution
J001	No response from target	Check power and connections
J002	Invalid IDCODE	Verify target device type
J003	Chain length mismatch	Recount devices in chain
J004	IR scan failed	Check TDI/TDO connections
J005	Boundary scan error	Reduce frequency, check signals

Getting Help¶

Self-Diagnosis¶

Built-in Diagnostics
- Run system self-test
- Check hardware status
- Review error logs
External Tools
- Use oscilloscope for signals
- Multimeter for power checks
- Logic analyzer for protocols

Community Support¶

Documentation
- Check this troubleshooting guide
- Review API documentation
- Search existing issues
Online Resources
- GitHub Issues
- Community forum
- Discord chat

Reporting Issues¶

When reporting problems, include:

System Information
- Firmware version
- Hardware revision
- Battery level
Problem Description
- Exact error messages
- Steps to reproduce
- Expected vs actual behavior
Environment Details
- Target device type
- Connection method
- External tools used
Logs and Data
- Relevant log files
- Screenshots if applicable
- Test results