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Initial submission of the PCem-Experimental source code.

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OBattler
2016-06-26 00:34:39 +02:00
parent 09d7c4384f
commit fd2a5bc9f5
610 changed files with 184352 additions and 0 deletions
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src/neat.c Normal file
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/*This is the chipset used in the AMI 286 clone model*/
#include "ibm.h"
#include "io.h"
#include "neat.h"
static uint8_t neat_regs[256];
static int neat_index;
static int neat_emspage[4];
void neat_write(uint16_t port, uint8_t val, void *priv)
{
switch (port)
{
case 0x22:
neat_index = val;
break;
case 0x23:
neat_regs[neat_index] = val;
switch (neat_index)
{
case 0x6E: /*EMS page extension*/
neat_emspage[3] = (neat_emspage[3] & 0x7F) | (( val & 3) << 7);
neat_emspage[2] = (neat_emspage[2] & 0x7F) | (((val >> 2) & 3) << 7);
neat_emspage[1] = (neat_emspage[1] & 0x7F) | (((val >> 4) & 3) << 7);
neat_emspage[0] = (neat_emspage[0] & 0x7F) | (((val >> 6) & 3) << 7);
break;
}
break;
case 0x0208: case 0x0209: case 0x4208: case 0x4209:
case 0x8208: case 0x8209: case 0xC208: case 0xC209:
neat_emspage[port >> 14] = (neat_emspage[port >> 14] & 0x180) | (val & 0x7F);
break;
}
}
uint8_t neat_read(uint16_t port, void *priv)
{
switch (port)
{
case 0x22:
return neat_index;
case 0x23:
return neat_regs[neat_index];
}
return 0xff;
}
void neat_writeems(uint32_t addr, uint8_t val)
{
ram[(neat_emspage[(addr >> 14) & 3] << 14) + (addr & 0x3FFF)] = val;
}
uint8_t neat_readems(uint32_t addr)
{
return ram[(neat_emspage[(addr >> 14) & 3] << 14) + (addr & 0x3FFF)];
}
void neat_init()
{
io_sethandler(0x0022, 0x0002, neat_read, NULL, NULL, neat_write, NULL, NULL, NULL);
io_sethandler(0x0208, 0x0002, neat_read, NULL, NULL, neat_write, NULL, NULL, NULL);
io_sethandler(0x4208, 0x0002, neat_read, NULL, NULL, neat_write, NULL, NULL, NULL);
io_sethandler(0x8208, 0x0002, neat_read, NULL, NULL, neat_write, NULL, NULL, NULL);
io_sethandler(0xc208, 0x0002, neat_read, NULL, NULL, neat_write, NULL, NULL, NULL);
}