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Add CPU instructions.

master
Fabien Freling 2015-05-20 16:37:56 +02:00
parent 763c81a1e2
commit c8b231d48a
1 changed files with 29 additions and 0 deletions
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29
src/cpu.ml
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@ -112,6 +112,15 @@ let run cpu (mem: Memory.map) =
let opcode = read_pc_byte cpu mem |> char_of_int in
(* Hexa.print_slice cartridge.full_rom cpu.reg.pc (cpu.reg.pc + 7); *)
match opcode with
(* 8-bit load *)
(* LD r,(HL) *)
| '\x7E' -> printf " LD \tA, (HL)\n";
let hl = merge_bytes cpu.reg.l cpu.reg.h in
cpu.reg.a <- Memory.get mem hl;
inc_cycles cpu 8;
| '\x00' -> printf " NOP\n";
inc_cycles cpu 4
@ -172,6 +181,15 @@ let run cpu (mem: Memory.map) =
inc_cycles cpu 8
end
| '\x34' -> printf " INC \t(HL)\n";
let hl = merge_bytes cpu.reg.l cpu.reg.h in
let v = Memory.get mem hl |> int_of_char in
cpu.flag.z <- v + 1 = 0;
cpu.flag.n <- false;
cpu.flag.h <- v = 0b00001111;
Memory.set mem hl (char_of_int (v + 1));
inc_cycles cpu 12
| '\x3E' -> let n = read_pc_byte cpu mem in
printf " LD \tA, 0x%02X\n" n;
@ -200,6 +218,12 @@ let run cpu (mem: Memory.map) =
Memory.set mem (0xFF00 + n) cpu.reg.a;
inc_cycles cpu 12
| '\xEA' -> let addr = read_pc_2bytes cpu mem in
printf " LD \t(0X%04X), A\n" addr;
Memory.set mem addr cpu.reg.a;
inc_cycles cpu 16
| '\xF0' -> let n = read_pc_byte cpu mem in
printf " LDH \tA, (0xFF%02X)\n" n;
cpu.reg.a <- Memory.get mem (0xFF00 + n);
@ -214,5 +238,10 @@ let run cpu (mem: Memory.map) =
cmp_A cpu n;
inc_cycles cpu 8
| '\xFB' -> printf " EI\n";
(* enable interrupts, IME=1 *)
inc_cycles cpu 4
| x -> eprintf "opcode 0x%02X\n" (int_of_char x);
eprintf "#cycles: %d\n" cpu.cycles;
failwith "Unimplemented opcode."