Re: [stella] PROMs and bitrot

Subject: Re: [stella] PROMs and bitrot
From: Kevin Horton <khorton@xxxxxxxxxxx>
Date: Fri, 07 Dec 2001 22:05:47 -0500
At 18:42 12/7/01 -0800, you wrote:
Are PROMS equally succeptible to bitrot as EPROMS or are they as safe as masked ROMs?

PROMs cannot be used for game storage since they aren't even made any more (AFAIK), they suck power like it's going out of style, and they don't come in sizes big enough for games. They top out in size around 1K bits or thereabouts last I checked. Also, I'd trust an EPROM over a PROM any day in the reliability department. If you must have "secure" game storage, I suggest flash since it's got a 40+ year retention.

Realistically, people are best off using EPROMs for carts. If the game data must be saved, it's best to simply copy it and burn it onto CDR or some other "secure" and easily backed up storage media.

Heck, mask ROMs aren't immune to problems. I've got a 2600 cart that has some bad locations on it causing the game to not work properly.

Also, does anyone know the setup cost for making a masked ROM? You'd think technology improvements would lower the cost for this, as it has for other forms of media mastering (CD, DVD, etc...)

It is really expensive, and I doubt you can even get them in sizes smaller than 256Kbytes these days. Prolly looking at 10K-30K piece minimum order and a hefty tooling fee, in excess of $10K. They still gotta generate the die mask then shrink it down to make the sillycon.

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