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From: cb@sequoia.UUCP (Christopher D. Brown)
Newsgroups: comp.sys.ibm.pc
Subject: Re: HELP:  with EGA/VGA page-to-page memory copy
Message-ID: <602@sequoia.UUCP>
Date: 28 Jul 89 14:13:07 GMT
References: <1495@dukeac.UUCP>
Reply-To: cb@sequoia.UUCP ()
Organization: Execucom Systems Corp., Austin, Texas
Lines: 31

In article <1495@dukeac.UUCP> tcamp@dukeac.UUCP (Ted A. Campbell) writes:
...
>	for ( i = 1; i < 10; i *= 2 )
>		{
>		outp( 0x3CE, 0x04 );		/* set read map    */
>		outp( 0x3CF, i );		/* to plane 'i'    */
>		outp( 0x3C4, 0x02 );		/* set write map   */
>		outp( 0x3C5, i );		/* to plane 'i'    */
>		memcpy( (char *) 0xa0000000,	/* copy to here    */
>			(char *) 0xa8000000,	/* from here       */
>			(size_t) 0x8000 );      /* this many bytes */
>		}
>
>But this doesn't work and I'm not even sure why:  some copying is being 
...

Close.  Try the following ...
   for ( z = 0; z < 4; ++z )
   {
      outp( 0x3CE, 0x04 );              /* set read map    */
      outp( 0x3CF, z );                 /* to plane 'i'    */
      outp( 0x3C4, 0x02 );              /* set write map   */
      outp( 0x3C5, 1 << z );            /* to plane 'i'    */
      memcpy( (char *) 0xa0000000,      /* copy to here    */
         (char *) 0xa8000000,           /* from here       */
         (size_t) 0x8000 );             /* this many bytes */
   }

chris brown
Net: cb!execu@cs.texas.edu
Voice: (512) 346-4980