Debugging Braille Display Drivers

hwIo Debugging

If the driver you want to debug uses the hwIo module (for raw input/output) and/or the hwPortUtils module (for scanning for devices), these modules can optionally provide detailed debug logging. For hwIo, this includes all data sent and received. For hwPortUtils, this includes all devices found.

To enable this, follow these instructions:

1. Open the NVDA menu and select Preferences -> General settings.
2. Set the Logging level to debug.
3. Press OK.
4. Press NVDA+control+z to open the NVDA Python console.
5. Paste the following command:

import config; config.conf["debugLog"]["hwIo"] = True

6. Close the Python console.
7. Save NVDA's configuration by pressing NVDA+control+c.

Once this is done, this extra information will be included in the NVDA log file, which you can access by selecting Tools -> View log from the NVDA menu.

Drivers which Don't Use hwIo

If the driver you want to debug does not use the hwIo module, the driver is responsible for its own input/output debug logging. This may mean you need to add debug logging calls to the driver yourself.