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©
2009 Microchip Technology Inc.
DS51806A-page 21
PIC18F46J50 FULL-SPEED USB
DEMONSTRATION BOARD
USER’S GUIDE
Appendix A. Troubleshooting Tips
This appendix gives solutions for common issues.
Problem 1:
The USB device enumerates correctly in Demo mode (and appears normal in the
Device Manager), but a new drive volume does not appear for the MSD interface.
Resolution:
See if the target system has a drive letter conflict.
Common operating systems typically assign USB mass storage volumes (such as
Flash memory devices and detachable CD-ROM or floppy drives) to the next available
drive letter (often “E:”). If, however, the automatically assigned drive letter has already
been assigned to some other device (such as a mapped network drive), a conflict can
occur with some Windows operating systems.
See Microsoft Knowledge Base article 297694 at the following link:
http://support.microsoft.com/kb/297694
To resolve this issue, do one of the following:
• Obtain the hotfix available from Microsoft
• Manually reassign the conflicting drive volume (such as a mapped network drive)
with a drive letter that is later in the alphabet (such as Z:)
Problem 2:
The USB device does not enumerate or appear in the Device Manager.
Resolution:
Verify the following:
• The microcontroller is powered
• Jumper cap, JP3, is installed so that the demonstration board is obtaining power
from the USB cable
• The microcontroller was programmed with the correct firmware
The factory default firmware can be restored onto the microcontroller any time by using
the ICSP programming header and programming the microcontroller with the file,
PIC18F46J50 FS USB Demo Board Factory Hex 23 Jan 2009.hex
. To do this:
1.
Launch the MPLAB IDE application and select the ICSP programmer and the
correct device (PIC18F46J50).
2.
Select File>Import.
3.
Select the file,
PIC18F46J50 FS USB Demo Board Factory Hex 23 Jan
2009.hex
.
4.
Attach the programmer and select Programmer>Program.