Retro/pcem
Watch
1
0
Fork
You've already forked pcem
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Changed registers used for EGA/VGA odd/even mode.

Browse source
This commit is contained in:
TomW 2015-08-14 21:54:42 +01:00
commit 3789398ca6
4 changed files with 16 additions and 9 deletions
Download patch file Download diff file Expand all files Collapse all files

9
src/vid_ega.c
View file

@ -77,6 +77,9 @@ void ega_out(uint16_t addr, uint8_t val, void *p)
ega->charsetb = (((val >> 2) & 3) * 0x10000) + 2;
ega->charseta = ((val & 3) * 0x10000) + 2;
break;
case 4:
ega->chain2_write = !(val & 4);
break;
}
break;
case 0x3ce:
@ -95,10 +98,10 @@ void ega_out(uint16_t addr, uint8_t val, void *p)
case 5:
ega->writemode = val & 3;
ega->readmode = val & 8;
ega->chain2_read = val & 0x10;
break;
case 6:
// pclog("Write mapping %02X\n", val);
ega->chain2 = val & 2;
switch (val & 0xc)
{
case 0x0: /*128k at A0000*/
@ -622,7 +625,7 @@ void ega_write(uint32_t addr, uint8_t val, void *p)
if (addr >= 0xB0000) addr &= 0x7fff;
else addr &= 0xffff;
if (ega->chain2)
if (ega->chain2_write)
{
writemask2 &= ~0xa;
if (addr & 1)
@ -755,7 +758,7 @@ uint8_t ega_read(uint32_t addr, void *p)
if (addr >= 0xb0000) addr &= 0x7fff;
else addr &= 0xffff;
if (ega->chain2)
if (ega->chain2_read)
{
readplane = (readplane & 2) | (addr & 1);
addr &= ~1;

2
src/vid_ega.h
View file

@ -23,7 +23,7 @@ typedef struct ega_t
int fast;
uint8_t colourcompare, colournocare;
int readmode, writemode, readplane;
int chain4, chain2;
int chain4, chain2_read, chain2_write;
uint8_t writemask;
uint32_t charseta, charsetb;

12
src/vid_svga.c
View file

@ -111,6 +111,7 @@ void svga_out(uint16_t addr, uint8_t val, void *p)
svga->charsetb += 0x8000;
break;
case 4:
svga->chain2_write = !(val & 4);
svga->chain4 = val & 8;
svga->fast = (svga->gdcreg[8] == 0xff && !(svga->gdcreg[3] & 0x18) && !svga->gdcreg[1]) && svga->chain4;
break;
@ -159,10 +160,13 @@ void svga_out(uint16_t addr, uint8_t val, void *p)
{
case 2: svga->colourcompare=val; break;
case 4: svga->readplane=val&3; break;
case 5: svga->writemode=val&3; svga->readmode=val&8; break;
case 5:
svga->writemode = val & 3;
svga->readmode = val & 8;
svga->chain2_read = val & 0x10;
break;
case 6:
// pclog("svga_out recalcmapping %p\n", svga);
svga->chain2 = val & 2;
if ((svga->gdcreg[6] & 0xc) != (val & 0xc))
{
// pclog("Write mapping %02X\n", val);
@ -741,7 +745,7 @@ void svga_write(uint32_t addr, uint8_t val, void *p)
writemask2=1<<(addr&3);
addr&=~3;
}
else if (svga->chain2)
else if (svga->chain2_write)
{
writemask2 &= ~0xa;
if (addr & 1)
@ -928,7 +932,7 @@ uint8_t svga_read(uint32_t addr, void *p)
return 0xff;
return svga->vram[addr];
}
else if (svga->chain2)
else if (svga->chain2_read)
{
readplane = (readplane & 2) | (addr & 1);
addr &= ~1;

2
src/vid_svga.h
View file

@ -31,7 +31,7 @@ typedef struct svga_t
int fast;
uint8_t colourcompare, colournocare;
int readmode, writemode, readplane;
int chain4, chain2;
int chain4, chain2_write, chain2_read;
uint8_t writemask;
uint32_t charseta, charsetb;