Rob, just a word of caution as I've sold some NVRAM products over the last year as well here on Pinside. You'll want to mention that on some board sets the existing RAM is soldered directly to the board (System 11, WPC, etc). That means if someone hasn't already installed a socket at the RAM chip, the end-user would need to cut the existing RAM off the board, unsolder the pins, clear the holes and install a brand new socket. I know you sometimes offer that type of service at shows or when you have the boards in for repair, but it also seems like you would also be selling just the adapter to the end-user via your website and they might be disappointed if they don't realize it's not an easy swap on some boards. Just trying to save you a headache there.

What's amazing with that DS1210 controller is how long the coin cell battery can last since it turns off battery power as soon as the machine is turned on and uses low power RAM. It was marketed as a way to turn RAM into NVRAM and it sure did that. I was looking into it a few months ago cause I was in awe at how at how a 285mah (CR2430?) can last 15-20 years or more.. have had several System 3 machines and they still hold high scores with the original battery and I've seen many other reports of that. Then after learning about that controller chip, it all made sense.

I have yet to see a System 3 with corrosion though and due to how long those batteries last with the controller chip, I'd agree that there probably wouldn't be much demand for it anyway. Pretty neat to generally not have to be concerned with battery corrosion on Gottlieb System 3 machines.

Kind of like this? http://pinside.com/pinball/forum/topic/judging-interest-nvram-for-stern-mpu-200

Well, I went the "daughter board" route instead of a socket because I wouldn't think that most people are going to want to be connecting jumper wires to a regular socket. Easier to make it plug-and-play and simplify installation with a separate pcb board IMO.

mpu200_nvram.jpg

Guess I'll not put as much priority on the System 1 nvram adapter I was working on. I had a similar setup on a prototype I recently had made, with a 6264 being adapted (allows people to use SRAM or compatible NVRAM that they already may have).

gottlieb_sys1_nvram_200.jpg

Assuming u2 is a tri-state buffer? Honesty I'm surprised someone else got around to working on this System 1's don't get a lot of love, so at least it means there will be some options for nvram on System 1 machines in the near future. I had tried testing my prototype in a Bally-35 mpu but then realized I was going to likely need to combine the OD, /CE and R/W pins there to get the enable signals for the buffer. The 5101 on the System 1 has OD and /CE permanently tied to ground though, so I'd think you could probably just combine CE2 & R/W (maybe what u1 is for on your board). Then if someone plugs it into something other than a System 1 mpu then they would just expect it to not function.