25 lines
744 B
C
25 lines
744 B
C
#include "../include/mapper.h"
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#include "../include/rom.h"
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#include <string.h>
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#define SIMPLE_MAPPER_PRG_START_ADDR 0x8000
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#define PRG_PART_SIZE 0x4000 // 16Kb
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void post_prg_load(ram ram, unsigned int prg_size) {
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if (prg_size == 2) {
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// The whole space is occupied, nothing to do
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return;
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}
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// We need to mirror the data in the upper ram
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byte *source = (byte *) &ram[SIMPLE_MAPPER_PRG_START_ADDR];
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byte *destination = (byte *) &ram[SIMPLE_MAPPER_PRG_START_ADDR + PRG_PART_SIZE];
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memcpy(destination, source, PRG_PART_SIZE);
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}
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Mapper get_simple_mapper() {
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Mapper mapper;
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mapper.prg_rom_start_addr = SIMPLE_MAPPER_PRG_START_ADDR;
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mapper.post_prg_load = &post_prg_load;
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return mapper;
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} |