Files
86Box-fork/src/jim.c

80 lines
2.5 KiB
C

#include <stdio.h>
#include <string.h>
#include "ibm.h"
#include "io.h"
uint8_t europcdat[16];
struct
{
uint8_t dat[16];
int stat;
int addr;
} europc_rtc;
void writejim(uint16_t addr, uint8_t val, void *p)
{
if ((addr&0xFF0)==0x250) europcdat[addr&0xF]=val;
switch (addr)
{
case 0x25A:
// printf("Write RTC stat %i val %02X\n",europc_rtc.stat,val);
switch (europc_rtc.stat)
{
case 0:
europc_rtc.addr=val&0xF;
europc_rtc.stat++;
// printf("RTC addr now %02X - contents %02X\n",val&0xF,europc_rtc.dat[europc_rtc.addr]);
break;
case 1:
europc_rtc.dat[europc_rtc.addr]=(europc_rtc.dat[europc_rtc.addr]&0xF)|(val<<4);
europc_rtc.stat++;
break;
case 2:
europc_rtc.dat[europc_rtc.addr]=(europc_rtc.dat[europc_rtc.addr]&0xF0)|(val&0xF);
europc_rtc.stat=0;
break;
}
break;
}
// printf("Write JIM %04X %02X\n",addr,val);
}
uint8_t readjim(uint16_t addr, void *p)
{
// printf("Read JIM %04X\n",addr);
switch (addr)
{
case 0x250: case 0x251: case 0x252: case 0x253: return 0;
case 0x254: case 0x255: case 0x256: case 0x257: return europcdat[addr&0xF];
case 0x25A:
if (europc_rtc.stat==1)
{
europc_rtc.stat=2;
return europc_rtc.dat[europc_rtc.addr]>>4;
}
if (europc_rtc.stat==2)
{
europc_rtc.stat=0;
return europc_rtc.dat[europc_rtc.addr]&0xF;
}
return 0;
}
return 0;
}
void jim_init()
{
uint8_t viddat;
memset(europc_rtc.dat,0,16);
europc_rtc.dat[0xF]=1;
europc_rtc.dat[3]=1;
europc_rtc.dat[4]=1;
europc_rtc.dat[5]=0x88;
if (gfxcard==GFX_CGA) viddat=0x12;
else if (gfxcard==GFX_MDA || gfxcard==GFX_HERCULES || gfxcard==GFX_INCOLOR) viddat=3;
else viddat=0x10;
europc_rtc.dat[0xB]=viddat;
europc_rtc.dat[0xD]=viddat; /*Checksum*/
io_sethandler(0x250, 0x10, readjim, NULL, NULL, writejim, NULL, NULL, NULL);
}