osViBlack [Function]

Function

osViBlack

Blacks out VI screen

Syntax

#include <ultra64.h>        /* os.h */
void osViBlack(u8 active);

Arguments

active

Blackout flag

TRUE (Set blackout)

FALSE (Cancel blackout)

Return Value

None.

Description

Allows the screen to be blacked out. Blacks out the screen after osViBlack is executed at the time that the first vertical retrace interrupt is generated. Vertical retrace signals continue to be generated while the screen is blacked out.

Precautions

If the coefficient for Y scale processing (yscale) is set to anything other than 1.0 with osViSetYScale when osViBlack is executed, return it to 1.0. In some instances, a reset will have no effect. Also, be sure to execute osViBlack after osCreateViManager.

Example

//      Starting VI manager & Blackout
        osCreateViManager(OS_PRIORITY_VIMGR);
#if (SCREEN_WD==320)&&(SCREEN_HT==240)            // Setting for low resolution
        osViSetMode(&osViModeNtscLan1);
#elif (SCREEN_WD==640)&&(SCREEN_HT==480)          // Setting for high resolution
        osViSetMode(&osViModeNtscHaf1]);
#else
#error  "Illegal Screen size"
#endif
        osViBlack(TRUE);

See Also

osViSetYScale

Revision History

02/01/99 Completely rewritten.