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#include "mapper_0000.c"
#include "mapper_0042.c"
static uint8_t mapper_default_ciram_read(struct nes_state *state, uint32_t addr) {
if(state->ines.mirroring == 0) { // Horizontal
addr = (addr & 0x800) | (addr & 0x3ff);
} else { // Vertical (default fallback)
addr = addr & 0x7ff;
}
return state->ciram[addr];
}
static void mapper_default_ciram_write(struct nes_state *state, uint32_t addr, uint8_t value) {
if(state->ines.mirroring == 0) {
addr = (addr & 0x800) | (addr & 0x3ff);
} else {
addr = addr & 0x7ff;
}
state->ciram[addr] = value;
}
static void mapper_default_tick(struct nes_state *state) { // No IRQ or timing logic needed
}
/*
* Mapper numbers are constructed like this: (submapper << 12 | mapperid) both in hex.
*
* NOTE(peter): Mapper 0 always has to be first!
*/
static struct mapper_entry mapper_table[] = {
/* Mapper: 0 */ { 0x00, mapper_0000_prg_read, mapper_0000_prg_write, mapper_0000_chr_read, mapper_0000_chr_write, mapper_default_ciram_read, mapper_default_ciram_write, mapper_default_tick, mapper_0000_init },
/* Mapper: 66 */ { 0x42, mapper_0042_prg_read, mapper_0042_prg_write, mapper_0042_chr_read, mapper_0042_chr_write, mapper_default_ciram_read, mapper_default_ciram_write, mapper_default_tick, mapper_0042_init },
};
static void mapper_setup(struct nes_state *state) {
uint32_t mapper = state->ines.mapper;
for(uint32_t i = 0; i < sizeof(mapper_table)/sizeof(mapper_table[0]); i++) {
if(mapper_table[i].id == mapper) {
state->mapper = mapper_table[i];
state->mapper.init(state);
return;
}
}
printf("Unsupported mapper %d, falling back to NROM\n", mapper);
state->mapper = mapper_table[0];
state->mapper.init(state);
}
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