Megatouch Security Key

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Megatouch Security Keys were, as the name implies, security keys that have a couple of different functions:

• Region-lock: As in, software for some regions (New Jersey for example) had specific features that had to be turned on for the Megatouch software to be legal in that jurisdiction.
• Version-lock: A version (and it's subsequent point-release) could only be run if a key of the same version was attached to the IO Board. For example, you can not run Maxx Jade with a Maxx Diamond key.

Hardware:

They are Dallas Keys or iButtons can be used for multiple purposes as there are many variants of it.

The type used in earlier Megatouch versions is the DS1991, a battery-powered chip with 1,152-bit secure read/write, nonvolatile memory. Said memory is partitioned into 3 blocks of 384 bits each, which are protected by a 64-bit password. Each key also has a 512-bit scratchpad. Their datasheet say they offer "over 10-year" retention.

Later (starting with 2007 versions) they started using the DS1995L-F5 version of the keys which has the following differences:

• 16384 bits of read/write nonvolatile memory
• Overdrive mode boosts communication speed to 142 kbits per second
• 256-bit scratchpad.
• Memory partitioned into 256-bit pages.

Merit's Part Numbers:

Megatouch Security Keys game version can (normally) easily be identified by looking at the Merit Part Number, which is normally printed on a sticker in the plastic holder which follows the format SA3xxx-yy where xxxx is the model and yy is the region of the key.

A list of known Megatouch Security Key Part Numbers has been graciously compiled by Mike of meritgames.com which you can access here.

I (Xeon3D) am currently in possession of a couple of keys which have part numbers that do not follow the SA3xxx-yy format (as they don't start with SA3).

Both of them are for Megatouch Jade, one with part number SA1020-01 and the other with SA0020-01. They both boot the Jade software without an issue and no noticeable differences are found.

Key Death & Solutions:

This "over 10-year" retention is quite important, as when the data is lost due to battery depletion, the games will not start. There are keys, known to be at least 25 years old, still working. There are also reports of quite younger keys already depleted. Do note that the serial number doesn't ever get erased, only the encrypted data.

Due to this, some solutions have appeared, namely:

• KeySaver - A Linux module that when installed will dump key contents and serial number into a file. As long as a key with the matching serial number is installed, the game will boot and work normally as keycontents are read from the file instead of the key itself.
• Keyless Patches - Patches made by another member of the community that make the software able to boot normally as key contents and serial are dumped to a file (similarly to KeySaver) but game is patched to read both from said file, unlike KeySaver which always reads Serial from key. This allows games to be booted with just an empty IO Board as long as hardware matches.
• IOBoardless Patches - Similar to Keyless patches, these also dump some IOBoard data to files, making it possible to run the software without any IOBoard.
• Megatouch Force Key of Death bypass instructions by www.arcade-cabinets.com (dead)

Unfortunately, these only work for Linux-based versions of Megatouch namely:

- Megatouch MAXX Ruby, Ruby 2, Sapphire, Sapphire 2, Jade, Jade 2 & Crown,

- Megatouch Force 2003 onwards (not 2002)

- Megatouch ION (all versions).