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LD, LDH, WRAM, and HRAM

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This commit is contained in:
Samuel Walker
2025-01-30 21:59:05 -07:00
parent 1bf98447a3
commit 022c24dd35
11 changed files with 458 additions and 58 deletions
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51
lib/cpu_proc.c
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@ -1,17 +1,9 @@
#include <cpu.h>
#include <emu.h>
#include <bus.h>
//process CPU instructions...
static void proc_none(cpu_context *ctx) {
printf("INVALID INSTRUCTION!\n");
exit(-7);
}
static void proc_nop(cpu_context *ctx) {
}
void cpu_set_flags(cpu_context *ctx, u8 z, u8 n, u8 h, u8 c){
if (z != -1){
BIT_SET(ctx->regs.f, 7, z)
@ -27,6 +19,24 @@ void cpu_set_flags(cpu_context *ctx, u8 z, u8 n, u8 h, u8 c){
}
}
static void proc_none(cpu_context *ctx) {
printf("INVALID INSTRUCTION!\n");
exit(-7);
}
static void proc_nop(cpu_context *ctx) {
}
static void proc_ldh(cpu_context *ctx) {
if (!ctx->dest_is_mem) {
cpu_set_reg(ctx->cur_inst->reg_1, bus_read(0XFF00 | ctx->fetched_data));
} else {
bus_write(0xFF00 | ctx->mem_dest, ctx->cur_inst->reg_2);
}
emu_cycles(1);
}
static void proc_xor(cpu_context *ctx) {
ctx->regs.a ^= ctx->fetched_data & 0XFF;
cpu_set_flags(ctx, ctx->regs.a == 0, 0, 0, 0);
@ -37,7 +47,25 @@ static void proc_di(cpu_context *ctx) {
}
static void proc_ld(cpu_context *ctx) {
//TODO
if(ctx->dest_is_mem) {
if(ctx->cur_inst->reg_2 >= RT_AF) {
bus_write16(ctx->mem_dest, ctx->fetched_data);
emu_cycles(1);
} else {
bus_write(ctx->mem_dest, ctx->fetched_data);
emu_cycles(1);
}
return;
}
if (ctx->cur_inst->mode == AM_HL_SPR) {
u8 hflag = (cpu_read_reg(ctx->cur_inst->reg_2) & 0xF) + (ctx->fetched_data & 0xF) >= 0x10;
u8 cflag = (cpu_read_reg(ctx->cur_inst->reg_2) & 0xFF) + (ctx->fetched_data & 0xFF) >= 0x100;
cpu_set_flags(ctx, 0, 0, hflag, cflag);
cpu_set_reg(ctx->cur_inst->reg_1, cpu_read_reg(ctx->cur_inst->reg_2) + (char)ctx->fetched_data);
}
cpu_set_reg(ctx->cur_inst->reg_1, ctx->fetched_data);
}
static bool check_condition(cpu_context *ctx) {
@ -68,7 +96,8 @@ IN_PROC processors[] = {
[IN_LD] = proc_ld,
[IN_JP] = proc_jp,
[IN_DI] = proc_di,
[IN_XOR] = proc_xor
[IN_XOR] = proc_xor,
[IN_LDH] = proc_ldh
};
IN_PROC inst_get_processor(in_type type) {