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SavePreferredConfiguration (csCode = 16)

The required SavePreferredConfiguration routine complements the GetPreferredConfiguration control routine. It is used by clients to save the preferred relative bit depth (depth mode) and display mode. This means that a PCI card should save this information in NVRAM so that it persists across system restarts. Note that NVRAM use is limited to 8 bytes. For more information about NVRAM in PCI-based of Power Macintosh computers, see Typical NVRAM Structure.



 
OSErr = Control(theDeviceRefNum, cscSavePreferredConfiguration,

                     &theVDSwitchInfo);

The Monitors control panel can use this routine to set the preferred resolution and update the resolution list displayed to the user. Following is the information that the control routine must return in the fields of the VDSwitchInfoRec record passed by SavePreferredConfiguration :

--> csMode: Relative bit depth of preferred resolution
--> csData: DisplayModeID of preferred resolution
-- csPage: Unused
-- csBaseAddr: Unused

Note

The driver is not required to save any of the information across reboots. However, it is strongly recommended that the relative bit depth and the DisplayModeID value be saved in NVRAM.