PCMCIA_SET_VPP callback function (ntddpcm.h)
The PCMCIA_SET_VPP interface routine sets the power level of the Vpp PCMCIA pin (secondary power source).
Syntax
PCMCIA_SET_VPP PcmciaSetVpp;
BOOLEAN PcmciaSetVpp(
[in, optional] PVOID Context,
[in] UCHAR VppLevel
)
{...}
Parameters
[in, optional] Context
Pointer to the context for the interface routine.
[in] VppLevel
Specifies the voltage level to set on the Vpp pin. VppLevel must be one of the following values:
PCMCIA_VPP_0V
Specifies that the voltage on the Vpp pin be set to zero volts and that the Vpp pin be disabled.
PCMCIA_VPP_12V
Specifies that the voltage on the Vpp pin be set to twelve volts.
PCMCIA_VPP_IS_VCC
Specifies that the voltage on the Vpp pin be set to equal the voltage on the Vcc (primary card power) pin.
Return value
The PCMCIA_SET_VPP interface routine returns TRUE after the requested voltage level is set.
Remarks
The PCMCIA_SET_VPP interface routine returns control to the caller after the requested voltage is established in a stable state for the card.
A caller must set the Context parameter to the context that is specified by the PCMCIA bus driver. The PCMCIA bus driver returns the context for the interface routines in the Context member of the same PCMCIA_INTERFACE_STANDARD structure that contains the pointers to the interface routines. If the Context parameter is not valid, system behavior is not defined, and the system might halt.
Callers of this routine can run at IRQL <= DISPATCH_LEVEL. To maintain overall system performance, it is recommended that drivers call this routine at IRQL < DISPATCH_LEVEL.
Requirements
Requirement | Value |
---|---|
Target Platform | Desktop |
Header | ntddpcm.h (include Ntddpcm.h) |
IRQL | <=DISPATCH_LEVEL (See Remarks section.) |