From 2e9e3424ecd6b2701ef8f479c939bbd4297ed77b Mon Sep 17 00:00:00 2001
From: Lior Halphon <LIJI32@gmail.com>
Date: Sat, 14 Jul 2018 21:52:54 +0300
Subject: [PATCH] Document some revision differences

---
 Core/apu.c    |  5 ++++-
 Core/gb.c     |  2 +-
 Core/gb.h     | 16 +++++++---------
 Core/memory.c | 34 +++++++++++++++++++++++++++++++---
 4 files changed, 43 insertions(+), 14 deletions(-)

diff --git a/Core/apu.c b/Core/apu.c
index 2da4346..260947d 100644
--- a/Core/apu.c
+++ b/Core/apu.c
@@ -381,7 +381,10 @@ void GB_apu_run(GB_gameboy_t *gb)
             if (gb->model == GB_MODEL_CGB_C) {
                 /* Todo: This was confirmed to happen on a CGB-C. This may or may not happen on pre-CGB models.
                    Because this degrades audio quality, and testing this on a pre-CGB device requires audio records,
-                   I'll assume these devices are innocent until proven guilty. */
+                   I'll assume these devices are innocent until proven guilty.
+                 
+                   Also happens on CGB-B, but not on CGB-D.
+                 */
                 gb->apu.current_lfsr_sample &= gb->apu.previous_lfsr_sample;
             }
             gb->apu.previous_lfsr_sample = gb->apu.noise_channel.lfsr & 1;
diff --git a/Core/gb.c b/Core/gb.c
index c3fa4cc..5f7b4f4 100644
--- a/Core/gb.c
+++ b/Core/gb.c
@@ -447,7 +447,7 @@ static void reset_ram(GB_gameboy_t *gb)
 {
     switch (gb->model) {
         case GB_MODEL_CGB_E:
-        default:
+        case GB_MODEL_AGB: /* Unverified */
             for (unsigned i = 0; i < gb->ram_size; i++) {
                 gb->ram[i] = (random() & 0xFF);
             }
diff --git a/Core/gb.h b/Core/gb.h
index 3254624..8cf487d 100644
--- a/Core/gb.h
+++ b/Core/gb.h
@@ -22,24 +22,22 @@
 
 #define GB_STRUCT_VERSION 13
 
-typedef enum {
 #ifdef GB_INTERNAL
-    GB_MODEL_FAMILY_MASK = 0xF00,
-    GB_MODEL_DMG_FAMILY = 0x000,
+#define GB_MODEL_FAMILY_MASK 0xF00
+#define GB_MODEL_DMG_FAMILY 0x000
+#define GB_MODEL_MGB_FAMILY 0x100
+#define GB_MODEL_CGB_FAMILY 0x200
 #endif
+
+typedef enum {
+
     // GB_MODEL_DMG_0 = 0x000,
     // GB_MODEL_DMG_A = 0x001,
     GB_MODEL_DMG_B = 0x002,
     // GB_MODEL_DMG_C = 0x003,
     // GB_MODEL_SGB = 0x004,
-#ifdef GB_INTERNAL
-    GB_MODEL_MGB_FAMILY = 0x100,
-#endif
     // GB_MODEL_MGB = 0x100,
     // GB_MODEL_SGB2 = 0x101,
-#ifdef GB_INTERNAL
-    GB_MODEL_CGB_FAMILY = 0x200,
-#endif
     // GB_MODEL_CGB_0 = 0x200,
     // GB_MODEL_CGB_A = 0x201,
     // GB_MODEL_CGB_B = 0x202,
diff --git a/Core/memory.c b/Core/memory.c
index 5f6a89a..b658fd5 100644
--- a/Core/memory.c
+++ b/Core/memory.c
@@ -252,12 +252,25 @@ static uint8_t read_high_memory(GB_gameboy_t *gb, uint16_t addr)
             case GB_MODEL_CGB_E:
             case GB_MODEL_AGB:
                 return (addr & 0xF0) | ((addr >> 4) & 0xF);
-            
+
+            /*
+            case GB_MODEL_CGB_D:
+                if (addr > 0xfec0) {
+                    addr |= 0xf0;
+                }
+                return gb->extra_oam[addr - 0xfea0];
+            */
+                
             case GB_MODEL_CGB_C:
+            /*
+             case GB_MODEL_CGB_B:
+             case GB_MODEL_CGB_A:
+             case GB_MODEL_CGB_0:
+             */
                 addr &= ~0x18;
                 return gb->extra_oam[addr - 0xfea0];
                 
-            default:
+            case GB_MODEL_DMG_B:
                 ;
         }
     }
@@ -544,11 +557,26 @@ static void write_high_memory(GB_gameboy_t *gb, uint16_t addr, uint8_t value)
                 gb->oam[addr & 0xFF] = value;
             }
             switch (gb->model) {
+                /*
+                case GB_MODEL_CGB_D:
+                    if (addr > 0xfec0) {
+                        addr |= 0xf0;
+                    }
+                    gb->extra_oam[addr - 0xfea0] = value;
+                    break;
+                 */
                 case GB_MODEL_CGB_C:
+                /*
+                 case GB_MODEL_CGB_B:
+                 case GB_MODEL_CGB_A:
+                 case GB_MODEL_CGB_0:
+                 */
                     addr &= ~0x18;
                     gb->extra_oam[addr - 0xfea0] = value;
                     break;
-                default:
+                case GB_MODEL_DMG_B:
+                case GB_MODEL_CGB_E:
+                case GB_MODEL_AGB:
                     break;
             }
             return;