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5. Device can write but cannot read
If the hardware does not work correctly under Windows 2000 or Windows XP then the problem is most likely a
hardware issue. Windows CE is not very tolerant of noisy hardware, so even "good" designs for Windows 2000
and XP may experience problems with Windows CE.
Another issue that has arisen with Windows CE is that different host devices support different bulk transfer sizes.
One method to attempt to resolve this is to reduce In Transfer Size to 64. This is the smallest possible transfer size
and will have a severe effect on performance, but should resolve most other issues. Larger values may be tried to
improve performance.
If a USB host CF card is being used, it may help to set the Raton bit in the configuration settings.
6. Bytes missing or data corrupt
This can occur when a host driver fails to send vendor commands properly which can result in the device running at
a different Baud rate to the one intended. The Baud rate can be verified easily by transferring data from PDA/target
to HyperTerminal.
Some host device drivers have been seen to lose packets of data which would also cause this problem.
7. Driver isn't sending or receiving any data
Sending and receiving data can be tested with an application such as VCPTest. However, this will not highlight
problems due to incorrect Baud rates. To check for the wrong Baud rate being set, try to transfer data from the
PDA/target to and from HyperTerminal.
