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Initial cpu and instruction parsing

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This commit is contained in:
Samuel Walker
2025-01-30 16:27:27 -07:00
parent 945b82a3ca
commit cd588671c4
12 changed files with 303 additions and 11 deletions
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29
lib/cpu_util.c Normal file
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@ -0,0 +1,29 @@
#include <cpu.h>
extern cpu_context ctx;
u16 reverse(u16 n) {
return ((n & 0XFF00) >> 8) | ((n & 0x00FF) << 8);
}
u16 cpu_read_reg(reg_type rt) {
switch(rt) {
case RT_A: return ctx.regs.a;
case RT_F: return ctx.regs.f;
case RT_B: return ctx.regs.b;
case RT_C: return ctx.regs.c;
case RT_D: return ctx.regs.d;
case RT_E: return ctx.regs.e;
case RT_H: return ctx.regs.h;
case RT_L: return ctx.regs.l;
case RT_AF: return reverse(*((u16 *)&ctx.regs.a));
case RT_BC: return reverse(*((u16 *)&ctx.regs.b));
case RT_DE: return reverse(*((u16 *)&ctx.regs.d));
case RT_HL: return reverse(*((u16 *)&ctx.regs.h));
case RT_PC: return ctx.regs.pc;
case RT_SP: return ctx.regs.sp;
default: return 0;
}
}