Update README.md

README.md

@@ -1 +1,111 @@
-# InfoNES64
+# InfoNES64
+
+A Nintendo Entertainment Emulator running on th Nintendo 64.  Run it on real hardware using a flash drive, or an emulator.
+
+> Note This project is more of a fun thing for me to try if it works. It runs way too slow to be really usable and playable and there is no sound. I don't know if the emulator will ever run at full speed. Help is always welcome. 
+
+It has a unlicensed built-in game ["Blade Buster"](https://www.rgcd.co.uk/2011/05/blade-buster-nes.html), but you can replace it with your own game. See below.
+
+Built with [Libdragon](https://github.com/DragonMinded/libdragon)
+
+The emulator code is ported from [Infones by Jay Kumogata](https://github.com/jay-kumogata/InfoNES)
+
+## Building from source
+
+1. Install the Libdragon SDK. For more info and instructions, see https://github.com/DragonMinded/libdragon
+2. Make sure the environment var N64_INST points to the installed SDK
+3. Get the sources and build
+
+````bash
+git clone https://github.com/fhoedemakers/InfoNES64.git
+cd InfoNes64
+make
+````
+
+Then copy **infones64.z64** to your flash drive.
+
+## Replace the built-in game with your own rom
+
+One of the ways to do this is: 
+
+1. xxd -i myrom.nes > myrom.c
+2. Copy myrom.c to the assets folder
+3. edit myrom.c
+
+````C
+// Change the define
+#define BUILTINROMNAME "myrom"
+
+// Change murom_nes[] to builtinrom[]
+unsigned char builtinrom[] = {
+  0x4e, 0x45, 0x53, 0x1a, 0x10, 0x10, 0x42, 0x00, 0x00, 0x00, 0x00, 0x00,
+  0x00, 0x00, 0x00, 0x00, 0xa9, 0x08, 0x8d, 0x00, 0x20, 0xa9, 0x00, 0x8d,
+  0x01, 0x20, 0x20, 0xd6, 0xe1, 0x20, 0xeb, 0xe2, 0xa9, 0x00, 0x20, 0xe6,
+  0xd0, 0xa0, 0x0c, 0x84, 0xe
+
+...
+
+ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+  0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
+  0xff, 0xff, 0xff, 0xff
+};
+// change variabele from myrom_nes_len to builtinrom
+unsigned int builtinrom_len = 393232;
+````
+
+4. Edit builtinrom.c
+
+Insert
+
+#ifdef BUILTINROM_MYROM  
+#include "myrom.c"  
+#endif  
+
+as shown below
+
+````C
+#include "builtinrom.h"
+#ifdef BUILTINROM_BLADEBUSTER
+#include "bladebuster.c"
+#endif
+#ifdef BUILTINROM_SMB3
+#include "smb3.c"
+#endif
+#ifdef BUILTINROM_GALAGA
+#include "galaga.c"
+#endif
+#ifdef BUILTINROM_CV1
+#include "CV1.c"
+#endif
+#ifdef BUILTINROM_CV2
+#include "CV2.c"
+#endif
+#ifdef BUILTINROM_CV3
+#include "CV3.c"  // not working
+#endif
+#ifdef BUILTINROM_MYROM
+#include "myrom.c"
+#endif
+````
+
+5. edit builtinrom.h
+
+````C
+#pragma once
+
+// Specify the name of the built-in ROM to include
+#define BUILTINROM_MYROM
+extern unsigned char builtinrom[];
+extern unsigned int builtinrom_len;
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+char *GetBuiltinROMName();
+#ifdef __cplusplus
+}
+#endif
+````
+