pcem/src/vid_olivetti_m24.c
2013-04-21 14:54:35 +01:00

428 lines
19 KiB
C

/*Olivetti M24 video emulation
Essentially double-res CGA*/
#include "ibm.h"
#include "video.h"
static uint8_t m24_ctrl;
static uint32_t m24_base;
void m24_out(uint16_t addr, uint8_t val)
{
uint8_t old;
switch (addr)
{
case 0x3D4:
crtcreg = val & 31;
return;
case 0x3D5:
old = crtc[crtcreg];
crtc[crtcreg] = val & crtcmask[crtcreg];
if (old != val)
{
if (crtcreg < 0xE || crtcreg > 0x10)
{
fullchange = changeframecount;
m24_recalctimings();
}
}
return;
case 0x3D8:
cgamode = val;
return;
case 0x3D9:
cgacol = val;
return;
case 0x3de:
m24_ctrl = val;
m24_base = (val & 0x08) ? 0x4000 : 0;
return;
}
}
uint8_t m24_in(uint16_t addr)
{
switch (addr)
{
case 0x3D4:
return crtcreg;
case 0x3D5:
return crtc[crtcreg];
case 0x3DA:
return cgastat;
}
return 0xFF;
}
static uint8_t charbuffer[256];
void m24_write(uint32_t addr, uint8_t val)
{
vram[addr & 0x7FFF]=val;
charbuffer[ ((int)(((dispontime - vidtime) * 2) / (CGACONST / 2))) & 0xfc] = val;
charbuffer[(((int)(((dispontime - vidtime) * 2) / (CGACONST / 2))) & 0xfc) | 1] = val;
}
uint8_t m24_read(uint32_t addr)
{
return vram[addr & 0x7FFF];
}
void m24_recalctimings()
{
if (cgamode & 1)
{
disptime = crtc[0] + 1;
dispontime = crtc[1];
}
else
{
disptime = (crtc[0] + 1) << 1;
dispontime = crtc[1] << 1;
}
dispofftime = disptime - dispontime;
// printf("%i %f %f %f %i %i\n",cgamode&1,disptime,dispontime,dispofftime,crtc[0],crtc[1]);
dispontime *= CGACONST / 2;
dispofftime *= CGACONST / 2;
// printf("Timings - on %f off %f frame %f second %f\n",dispontime,dispofftime,(dispontime+dispofftime)*262.0,(dispontime+dispofftime)*262.0*59.92);
}
static int linepos,displine;
static int sc,vc;
static int cgadispon;
static int con,coff,cursoron,cgablink;
static int vsynctime,vadj;
static int m24_lineff = 0;
static uint16_t ma,maback,ca;
void m24_poll()
{
uint16_t ca=(crtc[15]|(crtc[14]<<8))&0x3FFF;
int drawcursor;
int x,c;
int oldvc;
uint8_t chr,attr;
uint16_t dat,dat2,dat3,dat4;
int cols[4];
int col;
int oldsc;
if (!linepos)
{
// pclog("Line poll %i %i %i %i - %04X %i %i %i\n", m24_lineff, vc, sc, vadj, ma, firstline, lastline, displine);
vidtime+=dispofftime;
cgastat|=1;
linepos=1;
oldsc=sc;
if ((crtc[8]&3)==3) sc=(sc<<1)&7;
if (cgadispon)
{
if (displine<firstline)
{
firstline=displine;
// printf("Firstline %i\n",firstline);
}
lastline=displine;
for (c=0;c<8;c++)
{
if ((cgamode&0x12)==0x12)
{
buffer->line[displine][c]=0;
if (cgamode&1) buffer->line[displine][c+(crtc[1]<<3)+8]=0;
else buffer->line[displine][c+(crtc[1]<<4)+8]=0;
}
else
{
buffer->line[displine][c]=(cgacol&15)+16;
if (cgamode&1) buffer->line[displine][c+(crtc[1]<<3)+8]=(cgacol&15)+16;
else buffer->line[displine][c+(crtc[1]<<4)+8]=(cgacol&15)+16;
}
}
if (cgamode&1)
{
for (x=0;x<crtc[1];x++)
{
chr = charbuffer[ x << 1];
attr = charbuffer[(x << 1) + 1];
drawcursor=((ma==ca) && con && cursoron);
if (cgamode&0x20)
{
cols[1]=(attr&15)+16;
cols[0]=((attr>>4)&7)+16;
if ((cgablink&16) && (attr&0x80) && !drawcursor) cols[1]=cols[0];
}
else
{
cols[1]=(attr&15)+16;
cols[0]=(attr>>4)+16;
}
if (drawcursor)
{
for (c=0;c<8;c++)
buffer->line[displine][(x<<3)+c+8]=cols[(fontdatm[chr][((sc & 7) << 1) | m24_lineff]&(1<<(c^7)))?1:0]^15;
}
else
{
for (c=0;c<8;c++)
buffer->line[displine][(x<<3)+c+8]=cols[(fontdatm[chr][((sc & 7) << 1) | m24_lineff]&(1<<(c^7)))?1:0];
}
ma++;
}
}
else if (!(cgamode&2))
{
for (x=0;x<crtc[1];x++)
{
chr=vram[((ma<<1)&0x3FFF) + m24_base];
attr=vram[(((ma<<1)+1)&0x3FFF) + m24_base];
drawcursor=((ma==ca) && con && cursoron);
if (cgamode&0x20)
{
cols[1]=(attr&15)+16;
cols[0]=((attr>>4)&7)+16;
if ((cgablink&16) && (attr&0x80)) cols[1]=cols[0];
}
else
{
cols[1]=(attr&15)+16;
cols[0]=(attr>>4)+16;
}
ma++;
if (drawcursor)
{
for (c=0;c<8;c++)
buffer->line[displine][(x<<4)+(c<<1)+8]=buffer->line[displine][(x<<4)+(c<<1)+1+8]=cols[(fontdatm[chr][((sc & 7) << 1) | m24_lineff]&(1<<(c^7)))?1:0]^15;
}
else
{
for (c=0;c<8;c++)
buffer->line[displine][(x<<4)+(c<<1)+8]=buffer->line[displine][(x<<4)+(c<<1)+1+8]=cols[(fontdatm[chr][((sc & 7) << 1) | m24_lineff]&(1<<(c^7)))?1:0];
}
}
}
else if (!(cgamode&16))
{
cols[0]=(cgacol&15)|16;
col=(cgacol&16)?24:16;
if (cgamode&4)
{
cols[1]=col|3;
cols[2]=col|4;
cols[3]=col|7;
}
else if (cgacol&32)
{
cols[1]=col|3;
cols[2]=col|5;
cols[3]=col|7;
}
else
{
cols[1]=col|2;
cols[2]=col|4;
cols[3]=col|6;
}
for (x=0;x<crtc[1];x++)
{
dat=(vram[((ma<<1)&0x1FFF)+((sc&1)*0x2000) + m24_base]<<8)|vram[((ma<<1)&0x1FFF)+((sc&1)*0x2000)+1 + m24_base];
ma++;
for (c=0;c<8;c++)
{
buffer->line[displine][(x<<4)+(c<<1)+8]=
buffer->line[displine][(x<<4)+(c<<1)+1+8]=cols[dat>>14];
dat<<=2;
}
}
}
else
{
if (m24_ctrl & 1)
{
dat2 = ((sc & 1) * 0x4000) | (m24_lineff * 0x2000);
cols[0]=0; cols[1]=/*(cgacol&15)*/15+16;
}
else
{
dat2 = (sc & 1) * 0x2000;
cols[0]=0; cols[1]=(cgacol&15)+16;
}
for (x=0;x<crtc[1];x++)
{
dat=(vram[((ma<<1)&0x1FFF) + dat2]<<8) | vram[((ma<<1)&0x1FFF) + dat2 + 1];
ma++;
for (c=0;c<16;c++)
{
buffer->line[displine][(x<<4)+c+8]=cols[dat>>15];
dat<<=1;
}
}
}
}
else
{
cols[0]=((cgamode&0x12)==0x12)?0:(cgacol&15)+16;
if (cgamode&1) hline(buffer,0,displine,(crtc[1]<<3)+16,cols[0]);
else hline(buffer,0,displine,(crtc[1]<<4)+16,cols[0]);
}
if (cgamode&1) x=(crtc[1]<<3)+16;
else x=(crtc[1]<<4)+16;
sc=oldsc;
if (vc==crtc[7] && !sc)
cgastat|=8;
displine++;
if (displine>=720) displine=0;
}
else
{
// pclog("Line poll %i %i %i %i\n", m24_lineff, vc, sc, vadj);
vidtime+=dispontime;
if (cgadispon) cgastat&=~1;
linepos=0;
m24_lineff ^= 1;
if (m24_lineff)
{
ma = maback;
}
else
{
if (vsynctime)
{
vsynctime--;
if (!vsynctime)
cgastat&=~8;
}
if (sc==(crtc[11]&31) || ((crtc[8]&3)==3 && sc==((crtc[11]&31)>>1))) { con=0; coff=1; }
if (vadj)
{
sc++;
sc&=31;
ma=maback;
vadj--;
if (!vadj)
{
cgadispon=1;
ma=maback=(crtc[13]|(crtc[12]<<8))&0x3FFF;
sc=0;
}
}
else if (sc==crtc[9] || ((crtc[8]&3)==3 && sc==(crtc[9]>>1)))
{
maback=ma;
sc=0;
oldvc=vc;
vc++;
vc&=127;
if (vc==crtc[6])
cgadispon=0;
if (oldvc==crtc[4])
{
vc=0;
vadj=crtc[5];
if (!vadj) cgadispon=1;
if (!vadj) ma=maback=(crtc[13]|(crtc[12]<<8))&0x3FFF;
if ((crtc[10]&0x60)==0x20) cursoron=0;
else cursoron=cgablink&16;
}
if (vc==crtc[7])
{
cgadispon=0;
displine=0;
vsynctime=(crtc[3]>>4)+1;
if (crtc[7])
{
if (cgamode&1) x=(crtc[1]<<3)+16;
else x=(crtc[1]<<4)+16;
lastline++;
if (x!=xsize || (lastline-firstline)!=ysize)
{
xsize=x;
ysize=lastline-firstline;
if (xsize<64) xsize=656;
if (ysize<32) ysize=200;
updatewindowsize(xsize, ysize + 16);
}
startblit();
video_blit_memtoscreen_8(0, firstline - 8, xsize, (lastline - firstline) + 16);
if (readflash) rectfill(screen,winsizex-40,8,winsizex-8,14,0xFFFFFFFF);
readflash=0;
frames++;
endblit();
video_res_x = xsize - 16;
video_res_y = ysize;
if (cgamode & 1)
{
video_res_x /= 8;
video_res_y /= (crtc[9] + 1) * 2;
video_bpp = 0;
}
else if (!(cgamode & 2))
{
video_res_x /= 16;
video_res_y /= (crtc[9] + 1) * 2;
video_bpp = 0;
}
else if (!(cgamode&16))
{
video_res_x /= 2;
video_res_y /= 2;
video_bpp = 2;
}
else if (!(m24_ctrl & 1))
{
video_res_y /= 2;
video_bpp = 1;
}
}
firstline=1000;
lastline=0;
cgablink++;
}
}
else
{
sc++;
sc&=31;
ma=maback;
}
if ((sc==(crtc[10]&31) || ((crtc[8]&3)==3 && sc==((crtc[10]&31)>>1)))) con=1;
}
if (cgadispon && (cgamode&1))
{
for (x=0;x<(crtc[1]<<1);x++)
charbuffer[x]=vram[(((ma<<1)+x)&0x3FFF) + m24_base];
}
}
}
int m24_init()
{
mem_sethandler(0xb8000, 0x08000, m24_read, NULL, NULL, m24_write, NULL, NULL);
return 0;
}
GFXCARD vid_m24 =
{
m24_init,
/*IO at 3Cx/3Dx*/
m24_out,
m24_in,
/*IO at 3Ax/3Bx*/
video_out_null,
video_in_null,
m24_poll,
m24_recalctimings,
video_write_null,
video_write_null,
m24_write,
video_read_null,
video_read_null,
m24_read
};