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AmigActive 10
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AACD 10.iso
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AACD
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MAME
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src
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machine
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asteroid.c
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C/C++ Source or Header
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2000-04-04
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173 lines
/***************************************************************************
machine.c
Functions to emulate general aspects of the machine (RAM, ROM, interrupts,
I/O ports)
***************************************************************************/
#include "driver.h"
#include "machine/atari_vg.h"
#include "vidhrdw/avgdvg.h"
int asteroid_interrupt (void)
{
/* Turn off interrupts if self-test is enabled */
if (readinputport(0) & 0x80)
return ignore_interrupt();
else
return nmi_interrupt();
}
int llander_interrupt (void)
{
/* Turn off interrupts if self-test is enabled */
if (readinputport(0) & 0x02)
return nmi_interrupt();
else
return ignore_interrupt();
}
READ_HANDLER( asteroid_IN0_r )
{
int res;
int bitmask;
res=readinputport(0);
bitmask = (1 << offset);
if (cpu_gettotalcycles() & 0x100)
res |= 0x02;
if (!avgdvg_done())
res |= 0x04;
if (res & bitmask)
res = 0x80;
else
res = ~0x80;
return res;
}
READ_HANDLER( asteroib_IN0_r )
{
int res;
res=readinputport(0);
// if (cpu_gettotalcycles() & 0x100)
// res |= 0x02;
if (!avgdvg_done())
res |= 0x80;
return res;
}
/*
* These 7 memory locations are used to read the player's controls.
* Typically, only the high bit is used. This is handled by one input port.
*/
READ_HANDLER( asteroid_IN1_r )
{
int res;
int bitmask;
res=readinputport(1);
bitmask = (1 << offset);
if (res & bitmask)
res = 0x80;
else
res = ~0x80;
return (res);
}
READ_HANDLER( asteroid_DSW1_r )
{
int res;
int res1;
res1 = readinputport(2);
res = 0xfc | ((res1 >> (2 * (3 - (offset & 0x3)))) & 0x3);
return res;
}
WRITE_HANDLER( asteroid_bank_switch_w )
{
static int asteroid_bank = 0;
int asteroid_newbank;
unsigned char *RAM = memory_region(REGION_CPU1);
asteroid_newbank = (data >> 2) & 1;
if (asteroid_bank != asteroid_newbank) {
/* Perform bankswitching on page 2 and page 3 */
int temp;
int i;
asteroid_bank = asteroid_newbank;
for (i = 0; i < 0x100; i++) {
temp = RAM[0x200 + i];
RAM[0x200 + i] = RAM[0x300 + i];
RAM[0x300 + i] = temp;
}
}
osd_led_w (0, ~(data >> 1));
osd_led_w (1, ~data);
}
WRITE_HANDLER( astdelux_bank_switch_w )
{
static int astdelux_bank = 0;
int astdelux_newbank;
unsigned char *RAM = memory_region(REGION_CPU1);
astdelux_newbank = (data >> 7) & 1;
if (astdelux_bank != astdelux_newbank) {
/* Perform bankswitching on page 2 and page 3 */
int temp;
int i;
astdelux_bank = astdelux_newbank;
for (i = 0; i < 0x100; i++) {
temp = RAM[0x200 + i];
RAM[0x200 + i] = RAM[0x300 + i];
RAM[0x300 + i] = temp;
}
}
}
WRITE_HANDLER( astdelux_led_w )
{
osd_led_w (offset, ~data);
}
void asteroid_init_machine(void)
{
asteroid_bank_switch_w (0,0);
}
/*
* This is Lunar Lander's Inputport 0.
*/
READ_HANDLER( llander_IN0_r )
{
int res;
res = readinputport(0);
if (avgdvg_done())
res |= 0x01;
if (cpu_gettotalcycles() & 0x100)
res |= 0x40;
return res;
}