1991/1112/pc/vga.c (diff list | history)

1991/1109/sys/src/9/pc/vga.c:24,32 – 1991/1112/sys/src/9/pc/vga.c:24,32 (short | long | prev | next)
1991/0730		*/ #define MAXX 640 #define MAXY 480
1991/1109		#define XPERIOD 800 /* Hsync freq == 31.47 KHZ */ #define YPERIOD 525 /* Vsync freq == 59.9 HZ */ #define YBORDER 2
1991/1112		int xperiod = 800; /* Hsync freq == 31.47 KHZ */ int yperiod = 525; /* Vsync freq == 59.9 HZ */ int yborder = 7; /* top/bottom border of screen */
1991/0730		#define SCREENMEM (0xA0000 | KZERO)
1991/1109/sys/src/9/pc/vga.c:42,47 – 1991/1112/sys/src/9/pc/vga.c:42,51
1991/0730
1991/0723		enum {
1991/1112		EMISCR= 0x3CC, /* control sync polarity */ EMISCW= 0x3C2, EFCW= 0x3DA, /* feature control */ EFCR= 0x3CA,
1991/0723		GRX= 0x3CE, /* index to graphics registers */
1991/0727		GR= 0x3CF, /* graphics registers */ Grot= 0x03, /* data rotate register */
1991/1109/sys/src/9/pc/vga.c:115,120 – 1991/1112/sys/src/9/pc/vga.c:119,135
1991/0727		grout(Grms, p&3); }
1991/1112		vgadump(void) { print("misc is 0x%ux fc is 0x%ux\n", inb(EMISCR), inb(EFCR)); outb(EMISCW, 0xc7);/**/ } vgaclock(void) { outb(EMISCW, 0xc7);/**/ }
1991/0727		/*
1991/1109		* set up like vga mode 0x12 * 16 color (though we only use values 0x0 and 0xf)
1991/1109/sys/src/9/pc/vga.c:138,167 – 1991/1112/sys/src/9/pc/vga.c:153,182
1991/0928		* mem without modifications */
1991/1109		msl = overflow = 0;
1991/0928		crout(Cmode, 0xe3); /* turn off address wrap & * word mode */
1991/1112		/* turn off address wrap & word mode */ crout(Cmode, 0xe3);
1991/1109		/* last scan line displayed (first is 0) */ crout(Cvde, MAXY-1); overflow |= ((MAXY-1)&0x200) ? 0x40 : 0; overflow |= ((MAXY-1)&0x100) ? 0x2 : 0; /* total scan lines (including retrace) - 2 */ crout(Cvt, (YPERIOD-2)); overflow |= ((YPERIOD-2)&0x200) ? 0x20 : 0; overflow |= ((YPERIOD-2)&0x100) ? 0x1 : 0;
1991/1112		crout(Cvt, (yperiod-2)); overflow |= ((yperiod-2)&0x200) ? 0x20 : 0; overflow |= ((yperiod-2)&0x100) ? 0x1 : 0;
1991/1109		/* scan lines at which vertcal retrace starts & ends */ crout(Cvrs, (MAXY+10)); overflow |= ((MAXY+10)&0x200) ? 0x80 : 0; overflow |= ((MAXY+10)&0x100) ? 0x4 : 0; crout(Cvre, ((YPERIOD-1)&0xf)|0xa0); /* also disable vertical interrupts */
1991/1112		crout(Cvrs, (MAXY+0x0a)); /**/ overflow |= ((MAXY+0x0a)&0x200) ? 0x80 : 0; overflow |= ((MAXY+0x0a)&0x100) ? 0x4 : 0; crout(Cvre, ((yperiod-1)&0xf)|0xa0); /* also disable vertical interrupts */
1991/1109		/* scan lines at which vertical blanking starts & ends */ crout(Cvbs, (MAXY+YBORDER)); msl |= ((MAXY+YBORDER)&0x200) ? 0x20 : 0; overflow |= ((MAXY+YBORDER)&0x100) ? 0x8 : 0; crout(Cvbe, (YPERIOD-YBORDER)&0x7f); /* pixels per scan line (always 0 for graphics) */ crout(Cmsl, 0x40|msl); /* also 10th bit of line compare */
1991/1112		crout(Cvbs, (MAXY+yborder)); msl |= ((MAXY+yborder)&0x100) ? 0x20 : 0; overflow |= ((MAXY+yborder)&0x100) ? 0x8 : 0; crout(Cvbe, (yperiod-yborder)&0x7f);
1991/1109		/* the overflow bits from the other registers */ crout(Cvover, 0x10|overflow); /* also 9th bit of line compare */
1991/1112		/* pixels per scan line (always 0 for graphics) */ crout(Cmsl, 0x40|msl); /* also 10th bit of line compare */
1991/1109
1991/0928		srout(Smode, 0x06); /* extended memory, * odd/even off */