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GetSync (csCode = 11)

The use of the optional GetSync and SetSync routines has been expanded to manage the settings of all synchronization-related parameters of a frame buffer controller, not just the horizontal and vertical syncs. GetSync and SetSync can be used to implement the VESA DPMS as well as enable a sync-on-green mode for the frame buffer.

A VDSyncInfoRec data structure has been defined for the GetSync and SetSync routines:



 
struct VDSyncInfoRec {

    unsigned char       csMode; 

    unsigned char       csFlags;

}

The csMode parameter specifies the state of the sync lines according to these bit definitions:



 
enum {

    kDisableHorizontalSyncBit = 0,

    kDisableVerticalSyncBit = 1,

    kDisableCompositeSyncBit = 2,

    kEnableSyncOnBlue = 3,

    kEnableSyncOnGreen = 4,

    kEnableSyncOnRed = 5

};

To implement the DPMS standard, bits 0 and 1 of the csMode field should have the following values:

Bit 1	Bit 0	Status
0	0	Active
0	1	Standby
1	0	Idle
1	1	Off

GetSync can be used in two ways: to get the current status of the hardware and to get the capabilities of the frame buffer controller. These two different kinds of information are discussed in the next sections.