Initial cpu and instruction parsing

lib/bus.c

@@ -0,0 +1,32 @@
+#include <bus.h>
+
+// 0x0000 - 0x3FFF : ROM Bank 0
+// 0x4000 - 0x7FFF : ROM Bank 1 - Switchable
+// 0x8000 - 0x97FF : CHR RAM
+// 0x9800 - 0x9BFF : BG Map 1
+// 0x9C00 - 0x9FFF : BG Map 2
+// 0xA000 - 0xBFFF : Cartridge RAM
+// 0xC000 - 0xCFFF : RAM Bank 0
+// 0xD000 - 0xDFFF : RAM Bank 1-7 - switchable - Color only
+// 0xE000 - 0xFDFF : Reserved - Echo RAM
+// 0xFE00 - 0xFE9F : Object Attribute Memory
+// 0xFEA0 - 0xFEFF : Reserved - Unusable
+// 0xFF00 - 0xFF7F : I/O Registers
+// 0xFF80 - 0xFFFE : Zero Page
+
+u8 bus_read(u16 address) {
+    if(address < 0x8000) {
+        return cart_read(address);
+    }
+
+    NO_IMPL
+}
+
+void bus_write(u16 address, u8 value) {
+    if(address < 0x8000) {
+        cart_write(address);
+        return;
+    }
+
+    NO_IMPL
+}