fabs/oboy
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

Store full ROM in Cartridge.t

Browse source 
Now that the full ROM is stored, all fields are derived from it.
This commit is contained in:
Fabien Freling 2015-02-24 14:40:11 +01:00
parent 5cbd8c9794
commit 1a978d6814
1 changed files with 23 additions and 26 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

49
src/cartridge.ml
View file

@ -10,6 +10,7 @@ type memory_bank_controller =
| MBC1
type t = {
full_rom : bytes;
nintendo_logo : bytes;
title : string;
(* mem_type : memory_bank_controller; *)
@ -28,8 +29,7 @@ let check_nintendo_logo cartridge =
(Bytes.compare cartridge.nintendo_logo reference) == 0
(** ROM size is expressed in KB *)
let get_ROM_size b =
match Bytes.get b 0 |> int_of_char with
let get_ROM_size = function
| 0x00 -> 32 (* no ROM banking *)
| 0x01 -> 64 (* 4 banks *)
| 0x02 -> 128 (* 8 banks *)
@ -44,8 +44,7 @@ let get_ROM_size b =
| _ -> raise Read_error
(** RAM size is expressed in KB *)
let get_RAM_size b =
match Bytes.get b 0 |> int_of_char with
let get_RAM_size = function
| 0x00 -> 0
| 0x01 -> 2
| 0x02 -> 8
@ -55,41 +54,39 @@ let get_RAM_size b =
let read_cartridge file =
try
let fd = openfile file [Unix.O_RDONLY] 0o644 in
let ic = open_in_bin file in
let file_size = in_channel_length ic in
let full_rom = Bytes.create file_size in
really_input ic full_rom 0 file_size;
close_in ic;
try
let nin_logo_offset = 0x0104 in
if (lseek fd nin_logo_offset SEEK_SET) != nin_logo_offset
then raise Read_error;
(* Nintendo logo *)
let nin_logo_offset = 0x0104 in
let nin_logo_size = 48 in
let nintendo_logo = Bytes.create nin_logo_size in
if (read fd nintendo_logo 0 nin_logo_size) != nin_logo_size
then raise Read_error;
let nintendo_logo = Bytes.sub full_rom nin_logo_offset nin_logo_size in
(* Title *)
let title_offset = 0x0134 in
let title_size = 16 in
let title_b = Bytes.create title_size in
if (read fd title_b 0 title_size) != title_size
then raise Read_error;
let title_b = Bytes.sub full_rom title_offset title_size in
let title = Bytes.to_string title_b in
(* ROM size *)
let byte = Bytes.create 1 in
let _ = lseek fd 4 SEEK_CUR in
if (read fd byte 0 1) != 1
then raise Read_error;
let rom_size = get_ROM_size byte in
let rom_size_code = Bytes.get full_rom 0x0148 |> int_of_char in
let rom_size = get_ROM_size rom_size_code in
(* RAM size *)
if (read fd byte 0 1) != 1
then raise Read_error;
let ram_size = get_RAM_size byte in
let ram_size_code = Bytes.get full_rom 0x0149 |> int_of_char in
let ram_size = get_RAM_size ram_size_code in
Unix.close fd;
Some { nintendo_logo; title; rom_size; ram_size }
Some { full_rom; nintendo_logo; title; rom_size; ram_size }
with Read_error -> Unix.close fd; None
with
| Invalid_argument(msg) -> None (* This is triggered by Bytes.sub *)
| Read_error -> None
with Unix_error(err, cmd, msg) -> None
with Sys_error(msg) -> None