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HcdPdd_CheckConfigPower (Compact 2013)

3/26/2014

This function checks power for a requested configuration.

Syntax

BOOL HcdPdd_CheckConfigPower(
  UCHAR bPort,
  DWORD dwConfigPower,
  DWORD dwTotalPower 
);

Parameters

  • bPort
    [in] Root hub port number.
  • dwConfigPower
    [in] Power, in milliamps (mA), required by the configuration being checked.
  • dwTotalPower
    [in] Power, in mA, drawn by other devices on this port.

Return Value

TRUE indicates that the USB system supports the configuration. FALSE indicates that a configuration is not supported.

Remarks

When a device is initially attached to the bus, the host controller interface (HCI) selects a configuration, based on the power requirements of the system, by calling this function for each configuration until the HCI finds one that is supported. If no configurations in a device are supported, the device is not configured. This enables the platform to perform additional processing if necessary, such as checking whether the Windows Embedded Compact-based platform is using batteries or external power, or possibly sampling the power status of the current system.

Requirements

Header

Hcdddsi.h or Ohcdddsi.h

See Also

Reference

USB Host Controller Driver PDD Functions