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The PCCard and CF Card interfaces are identical from a signal and protocol point of view.

The PCCard driver needs to be disabled if no hardware environment is present (For example on the Protea carrier board, or on customer developed baseboards).

Bus Blocking

Any PCCard / CF Card has the option to slow down the system bus by pulling the PWAIT signal low. If the CF card interface is not implemented, the customer baseboard must either

  • Assure that the CF card driver is disabled


  • Assure (e.g. by pullups/pulldowns) that the combination PCD=1, PWAIT=0 never occurs.
    Otherwise the system bus will be halted by PWAIT at the time the PCCard driver is loaded, rendering the whole system non-responsive!

Disable PC Card driver

You can disable the driver by changing the value in the registry.


You must [save the registry](/windows-ce/knowledge-base/save-registry) to make the changes persistent.

For more registry settings see: CF card registry settings

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