From 763c81a1e28f88a5dec94426daf38e80ff35728b Mon Sep 17 00:00:00 2001
From: Fabien Freling <public@ffreling.com>
Date: Fri, 8 May 2015 14:48:44 +0200
Subject: [PATCH] Add CPU instructions.

---
 src/cpu.ml  | 33 +++++++++++++++++++++++++++------
 src/oboy.ml |  3 ---
 2 files changed, 27 insertions(+), 9 deletions(-)

diff --git a/src/cpu.ml b/src/cpu.ml
index 776e696..6948b18 100644
--- a/src/cpu.ml
+++ b/src/cpu.ml
@@ -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
 
diff --git a/src/oboy.ml b/src/oboy.ml
index 9fe8855..33f74be 100644
--- a/src/oboy.ml
+++ b/src/oboy.ml
@@ -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