l-com RS-422, Руководство пользователя

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USB to RS-422 / RS-485 Adapter
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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.