Brian Cassidy


Games::NES::ROM - View information about an NES game from a ROM file


    use Games::NES::ROM;
    # Read in the ROM without having to know its format
    my $rom = Games::NES::ROM->load( 'file.nes' );

    # Specifically read in an iNES file
    $rom = Games::NES::ROM::INES->new( filename => 'file.nes' );

    # Access the details
    print 'PRG Banks: ', $rom->prg_count, "\n";
    print 'CHR Banks: ', $rom->prg_count, "\n";
    # etc...
    # View the SHA-1 & CRC checksums
    print 'SHA1: ', $rom->sha1, "\n";
    print ' CRC: ', $rom->crc, "\n";


This module loads the details of an NES rom file. It is primarily meant to be used a base class for more specific file formats. Those formats include:


    perl Makefile.PL
    make test
    make install


load( $filename )

Attemps to read the ROM structure into memory using all available file formats until success.

prg_count( )

Returns the number of PRG banks for this ROM.

chr_count( )

Returns the number of CHR banks for this ROM.

sha1( )

Returns the SHA-1 checksum for the PRG and CHR data.

crc( )

Returns the CRC checksum for the PRG and CHR data.

sprite( $chr_bank, $index )

Returns the raw (composite) sprite in the specified CHR bank at the specified array index.


The following base attributes are available for all file formats:

  • filename - The filename from which data was loaded

  • id - A string found at the beginning of a file to identify the file format

  • title - The game's title, if available

  • prg_banks - An arrayref of PRG bank data

  • chr_banks - An arrayref of CHR bank data

  • has_sram - Boolean value to determine if the ROM is battery backed

  • mapper - A value indicating what memory mapper to use with the ROM

  • mirroring - A value indicating what time of mirroring is used in the ROM


  • mapper - iNES uses integer IDs, UNIF uses string IDs

  • mirroring - An integer ID, using the UNIF list as a basis

Each file format will have an extended set of attributes specific to its data structure. Please consult their documentation for more information.



Brian Cassidy <>


Copyright 2007-2013 by Brian Cassidy

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.