BlankScreen(D3nfb)

BlankScreen -- blank or unblank screen

Synopsis

#include "nfbScrStr.h"

Bool xxxBlankScreen (
	int on,
	ScreenPtr pScreen ) ;

Description

BlankScreen blanks the screen pointed to by pScreen if on is non-zero or unblanks it if on is zero. This is usually accomplished by disabling the CRTC.

Arguments

on: Set to TRUE to blank the screen; set to FALSE to unblank the screen.
pScreen: Identifies the screen to blank/unblank.

Exit codes

None

Usage

The NFB writer must satisfy this routine. The xmkddk script sets up this routine, prefixed with the driver's prefix; the driver writer must implement the functionality for the hardware. Most adapter hardware can handle this operation, but if yours cannot, the functionality can be implemented by setting all entries in the colormap to black.

Version applicability

This function is required for NFB drivers on all releases of SCO OpenServer 5, SVR5, and AIX 5L.

Source files

Routine source: None
Driver source file: xxxScreen.c

References

nfbScrnPriv(D4nfb)

Example

This is the BlankScreen( ) routine from the sample nte8 driver:

   Bool
   NTE(BlankScreen)(
   	int on,
   	ScreenPtr pScreen)
   {
   	unsigned char clk_mode;
   
   	NTE_OUTB(NTE_SEQX, NTE_CLK_MODE_INDEX);
   	clk_mode = NTE_INB(NTE_SEQ_DATA);
   

   	if (on)
   		clk_mode |= NTE_SCRN_OFF;
   	else
   		clk_mode &= ~NTE_SCRN_OFF;
   

   	NTE_OUTB(NTE_SEQ_DATA, clk_mode);
   

   	return TRUE;
   }