Understand the Endpoint Capture Issue
- Recognize Symptom Patterns: Often, the first indication of an endpoint capture issue with USBlyzer is incomplete or missing traces in your analysis. Check if specific endpoints fail to appear across multiple captures.
- Endpoint Configuration Oversight: Without correctly configuring endpoint filters, USBlyzer may skip critical traffic. Check the software documentation to ensure proper configuration.
Correcting Filters and Settings
- Adjust Filtering Options: Go to USBlyzer’s filter settings. Make sure you have enabled all the necessary endpoints that the device will use. If you are unsure, try capturing all endpoints to determine which ones are active.
- Modify Capture Range: USBlyzer might have a default data capture size. If your endpoint data surpasses this size, adjust this parameter using USBlyzer’s settings.
- Time Synchronization Check: Ensure that your system’s clock is synchronized to prevent timing conflicts affecting capture results.
Verification with USBlyzer
# Sample Python script for verifying if USB endpoint is configured correctly
import pyusb
def list_devices():
for bus in pyusb.busses():
for dev in bus.devices:
device = dev.open()
# Attempt to claim the active interface
try:
device.setConfiguration()
trace_device(device)
except Exception as e:
print(f"Error claiming interface: {e}")
def trace_device(dev):
ed = dev.get_active_configuration()[(0, 0)]
for endpoint in ed.endpoints():
addr = endpoint.bEndpointAddress
# Determine endpoint direction: In or Out
if (addr & pyusb.ENDPOINT_IN):
print(f"IN Endpoint detected: {addr}")
else:
print(f"OUT Endpoint detected: {addr}")
list_devices()
This snippet can be used to ensure that your endpoint configuration indeed matches your expectations and the recorded endpoints.
Troubleshoot USBlyzer Output
- Inspect Capture Logs: Analyze USBlyzer’s log files to identify any errors or warnings, which might explain missing captures or data limits.
- Utilize Verbose Mode: USBlyzer may have a verbose or advanced logging feature. Enable this to get a more detailed trace of USB operations.
Hardware and Driver Checks
- Confirm Hardware Connections: Ensure that all physical connections between your embedded device and host are secure. Faulty cables or ports often disrupt endpoint captures.
- Update Device Drivers: Outdated USB drivers can cause issues with device detection and endpoint capture. Make sure your drivers are up-to-date.
Leverage External Tools
- Cross-Verification: Use other USB analyzers to cross-verify USBlyzer results. An alternative tool may help confirm if the issue is software-based.
- Firmware Debugging Utility: Employ any available debugging utilities specific to your embedded system to see if the endpoint configuration from the device side matches the logs you expect.
Document Findings and Adjust
- Maintain a Log of Attempts and Results: Document each step taken during troubleshooting. This log can help identify patterns or provide valuable insight into fixing recurring issues.
Remember, resolving endpoint capture issues often involves a combination of proper configuration, monitoring, and adjustments, coupled with comprehensive debugging and analysis steps.