Doctor V64

The Doctor V64 (also referred to simply as the V64) is a development and backup device made by Bung Enterprises Ltd that is used in conjunction with the Nintendo 64. The Doctor V64 also had the ability to play Video CDs, audio CDs and had an option for applying stereo 3D effects to the audio.

The Doctor V64 came out in 1996 and was priced around $450 USD. Many third party developers used the V64 instead of the PC64 Development Kit sold by Nintendo; the V64 was considered an attractive, low cost alternative to the expensive N64 development machine, which was manufactured by Silicon Graphics at the time. The CPU of the V64 is a 6502 chip (the CPU from the Nintendo Entertainment System); the operating system is stored in the BIOS chip. It is likely that Bung reused most of the design of their earlier NES clones in the Doctor V64.

The Doctor V64 unit contains a CD-ROM drive which sits underneath the Nintendo 64 and plugs into the expansion slot on the underside of the Nintendo 64. The expansion slot is essentially a mirror image of the cartridge slot on the top of the unit, with the same electrical connections, thus the Nintendo 64 reads data from the Doctor V64 in the same manner as it would from a cartridge plugged into the normal slot.

Using the Doctor V64 involved the solution of two problems: how to boot a game and how to save. In order to get around Nintendo's lockout chip, when using the Doctor V64 a game cartridge is plugged into the Nintendo 64 through an adaptor which connects only the lockout chip. The game cart used for operation had to contain the same lockout chip used by the game backup. The second problem concerned saving progress. Most N64 games saved to the cart itself instead of external memory cards. If the player wanted to keep their progress then the cartridge used had to have the same type of non-volatile memory hardware.

Following the Doctor V64's success, Bung released the Doctor V64 Jr. in December 1998. This was a cost-efficient condensed version of the original V64. The V64jr had no CD drive and plugged into the normal cartridge slot on the top of the Nintendo 64. Data was loaded into the V64jr's battery-backed RAM from a PC via a parallel port connection. The V64Jr had up to 512 megabits (64 MB) of memory storage. At the time this was done to provide for future Nintendo 64 carts that employed larger memory storage. The prohibitive high costs associated with ordering large storage carts kept this occurrence at a minimum. Only a handful of 512 megabit games were released for the Nintendo 64 system.

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