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All:

Here’s a wacky one for you. I have a single board computer manufactured by Conversational Voice Terminal Company that appears to be a KIM-1 clone (same physical appearance, same chips, etc.). The source of the problem is that I have a memory expansion board for the KIM that doesn’t seem to work on this board. Now, I’m in the process of exchanging boards with a friend who has a known working memory board, but I’m wondering if there might be a subtle difference in the design of this board that’s causing the problem.

Has anyone heard of a KIM-1 clone made by this company? I got this board together with two real KIMs which happen to be non-working. The memory board was obtained separately and basically has very few parts (two chips – memory and inverter).

Rich

As a follow-up to this, I took a much closer look at the board (by now, a month or so ago) and discovered that this board uses 4k RAM chips. I guess that when I looked at the board quickly I didn't count the number of pins on the RAM chips so I didn't think there was a difference. Once I unplugged the third-party memory and re-loaded TinyBASIC, it worked fine.

I have never heard of such a clone. Since all the ICs, including the special KIM-1 6530s were available in these days, and the KIM-1 was also sold as OEM part, it is not surprising to see an actual clone. The price of the KIM-1 was rather low so I guess just buying the boards from Mos Technology and rebadging (one of mine has a Rockwell sticker on it!) was the easy way.
Later many companies did build KIM-1 like machines with one or two 6532 (like the MCS and Elektor clones). Ruud Baltissen did build a KIM-1 clone also with 6532's running the original KIM-1 roms!

It would be very nice for historical reference to have a photo of this board. Can you try that?

Hey Rich,

I did a clone of the KIM-1 I call the Micro-KIM. It is only 5X6 in size so it's a lot smaller than my KIM-1. Here's a picture:

http://www.brielcomputers.com/files/mk.jpg

Vince

Vince:

That's awesome! How did you replace the 6530s?

6532 like on Ruud's site, although his decoding was missing a little piece to make it correct. So far I've run about 8 KIM-1 programs and all of them work just fine. I need to find a good program that uses the onboard timer of the 6530 to make sure it runs the same as the 6532.

In theory, if somebody had a 6530 go bad, a replacement piggyback board could be made using an EPROM and a 6532 and a little decoding.

I'll try and get my schematics online soon for people to see and use.

Vince

The micro-KIM looks awesome Vince!

Thanks, I really am having fun with it. I didn't realize there was so much software out there for the KIM.

Vince

The Micro-KIM is a reality now. Vince did a great job!