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Add CPU instructions.

master
Fabien Freling 2015-05-08 14:48:44 +02:00
parent 7805e50062
commit 763c81a1e2
2 changed files with 27 additions and 9 deletions
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33
src/cpu.ml
View File

@ -97,7 +97,7 @@ let read_pc_byte cpu mem =
let b = Memory.get mem cpu.reg.pc in
inc_pc cpu 1;
int_of_char b
let read_pc_2bytes cpu mem =
let word = read_2B mem cpu.reg.pc in
inc_pc cpu 2;
@ -118,13 +118,26 @@ let run cpu (mem: Memory.map) =
| '\x03' -> printf " INC \tBC\n";
inc_BC cpu;
inc_cycles cpu 8
| '\x05' -> printf " DEC \tB\n";
let dec = int_of_char(cpu.reg.b) - 1 in
cpu.flag.z <- dec = 0;
cpu.flag.n <- true;
cpu.flag.h <- dec < 0;
cpu.reg.b <- char_of_int @@ if dec >= 0 then dec else 0;
inc_cycles cpu 4
| '\x06' -> let n = read_pc_byte cpu mem in
printf " LD \tB, 0x%02X\n" n;
cpu.reg.b <- char_of_int n;
inc_cycles cpu 8
| '\x18' -> let n = read_pc_byte cpu mem in
printf " JP\t 0x%02X\n" n;
printf " JP \t0x%02X\n" n;
inc_pc cpu (n - 1); inc_cycles cpu 12
| '\x20' -> let n = read_pc_byte cpu mem in
printf " JR\t NZ, 0x%02X\n" n;
printf " JR \tNZ, 0x%02X\n" n;
if cpu.flag.z = false then
begin
inc_pc cpu (n - 1); inc_cycles cpu 12
@ -134,15 +147,23 @@ let run cpu (mem: Memory.map) =
end
| '\x21' -> let nn = read_pc_2bytes cpu mem in
printf " LD\t HL, 0x%04X\n" nn;
printf " LD \tHL, 0x%04X\n" nn;
let high, low = split_2B nn in
cpu.reg.h <- high;
cpu.reg.l <- low;
inc_cycles cpu 12
| '\x22' -> printf " LDI \t(HL), A\n";
let hl = merge_bytes cpu.reg.l cpu.reg.h in
Memory.set mem hl cpu.reg.a;
let high, low = split_2B (hl + 1) in
cpu.reg.h <- high;
cpu.reg.l <- low;
inc_cycles cpu 8
| '\x28' -> let n = read_pc_byte cpu mem in
printf " JR\t Z, 0x%02X\n" n;
printf " JR \tZ, 0x%02X\n" n;
if cpu.flag.z = true then
begin
inc_pc cpu (n - 1); inc_cycles cpu 12
@ -189,7 +210,7 @@ let run cpu (mem: Memory.map) =
inc_cycles cpu 4
| '\xFE' -> let n = read_pc_byte cpu mem in
printf " CP\t0x%02X\n" n;
printf " CP \t0x%02X\n" n;
cmp_A cpu n;
inc_cycles cpu 8

3
src/oboy.ml
View File

@ -1,7 +1,6 @@
open Printf
let rec run (cpu: Cpu.t) (mem: Memory.map) =
let command = read_line () in
Cpu.run cpu mem;
run cpu mem
@ -17,8 +16,6 @@ let power_up cartridge =
let cpu = Cpu.init_cpu in
let mem = Memory.init cartridge in
Graphics.open_graph "";
Graphics.resize_window 256 256;
run cpu mem