• Please review our updated Terms and Rules here
  • From now on we will require that a prefix is set for any items in the sales area. We have created regions and locations for this. We also require that you select a delivery option before posting your listing. This will hopefully help us streamline the things that get listed for sales here and help local people better advertise their items, especially for local only sales. New sales rules are also coming, so stay tuned.

Looking to sell KIM-1

Dwight mentioned making boards for replacement of the 6530-002 and 6530-003. These ICs were programmable, but the program was "installed" at the factory, meaning that you bought the specific chip to do a specific job, and in the case of the KIM the jobs were integral to the functioning of the computer. For a description of the variants of the 6530, see here: https://en.wikipedia.org/wiki/MOS_Technology_RRIOT .

Since the 6530s were "custom" and made of "unobtainium", other people took the same approach as Dwight. Here is a design from someone who claims to have a working substitute: http://retro.hansotten.nl/6502-sbc/6530-6532/kim-1-6530-replacement/.

My point here is not to suggest you attempt this solution yourself, but rather to say that your KIM 1 board is not useless. You might offer it for sale, stating the condition with missing ICs clearly, but suggesting that a replacement strategy has been explored and posting a link to the retro posting. If a working KIM is worth $600 (averaging Dwight's range) then a non-working KIM has to be worth something: Ask for as much as you dare; you can always come down in price. But as my friend Peter used to say: "If you come cheap, you stay cheap."

-CH-
 
Thanks for the input, it definitely wouldn't be me trying to repair it, anything before win95 is one of life's great mysteries to me.
 
Hello, I would like to thank everyone who replied and offered help.
KIM-1 and bits are on their way to a new home.
 
Absolutely no problem.

Glad to be of service.

I hope the KIM-1 likes its new home and is back to working status shortly!

Dave
 
maggiepie said:
Hello Dave, yes these posts have been helpful at least I know more now than I did when I started. :)
Click to expand...
I’m late to the party and just came across this thread. Do you still have the KIM-1?

EDIT: Thanks, Dave, for the welcome and pointing me to post #25. Now that I’ve discovered this forum, I will continue my search! So great to find a community of fellow retro enthusiasts.
 
Last edited:
Welcome to VCFED (as this is your first post).

If you read post #25 you will see that the OP has moved the KIM-1 on to a new home...

Dave
 
Do note, the Corsham replacement doesn't properly emulate the interrupts. ( more a problem of the 6530 to 6532 difference ). Still most KIM-1 projects don't require the interrupts to be used. I believe that a swap of address bits can make it work but never tried it on real code. I did this swap on my adapter but not tried it. The interrupt controls are slightly different on the two chips. The Corsham boards are quite large and it is difficult to replace both 6530s as there is some space overlap issues. Corsham does have a lot of other great KIM-1 related products as well.
Do note that the most common failure on the KIM-1 was the RAM chips and and some of the TTL, not the 6530s. Many assumed the worst case and ended up damaging their boards. I designed a useful diagnostic board that anyone can make. It has information elsewhere on this forum on making a board or just wire wrapping it from the schematic. It helps to know if a 6530 is actually bad before damaging the board to replace a working part.
Dwight
 
rpmccoy said:
For future reference:

There is a solution for the 6530 problem. See this site : https://www.corshamtech.com/product/kim-1-6502-replacement/

its a 6530 replacement, even though the link says 6502 replacement.

I've used their products for several years.

Dick McCoy
Click to expand...
Sadly Bob Applegate passed away earlier this year, so it will be imposible to purchase any more corsham items. I was fortunate to work with Bob and purchase several of his KIM-1 add-on boards. Including the 6530 replacement board that I purchased for another KIM-1 that I was repairing for a friend. It was a great learning experience. Bob was always very helpful whenever I had a question on my KIM-1.
 
That is sad. I'd always intended to give my design to Bob but got side tracked. ( also accidentally deleted the layout for the small boards used for the 6532 to 6530, cleaning out what I thought were duplicates ) Recently, one of the other members used a recreation of my diagnostic board to bring up a failing KIM-1. As is usual, it was a RAM chip that had failed. I do have a few PC boards for the 6530, that would use a 6532 but it takes the diagnostic board to program them. It used a small EEPROM that hides under the socket with a PAL chip as well. I sold 10 kits so there are at least 10 of the parts kits out there to make a 6530 replacement. I very much doubt there was anything wrong with the 6530s, in this case. My board's failure was a special case of too many electrons, forced in, by the previous owner.
I guess, I should have offered buy the lady's board. I'm probably one of the few people that could replace both -002 and -003 chips at the same time, My replacement being small enough to fit under the 6532 with tiny overhang, blocking the other chips socket. The only issue is that the time to assemble the tiny boards would have exceeded the value of such a hacked board, in working state.
Doing such a project is a work of love or just crazy like me.

Dwight
 
I did reach out to you first. I would have preferred and in fact needed to replace both 6530s on the board I was working on. So, your small design would have been a better fit. Although I need something that was
already assembled and programmed. I do not under stand the whole using your test device to program. Once you get one programmed, I am assuming all you have to do is copy that to a chip burner and burn as many
as you would like after that.
I did enjoy learning more about the dead KIM-1 that I had. I even met the original owner, who ended up living in my small town. He had written his phone number on the case that the KIM-1 was installed in. He was using
the KIM-1 as some kind of radio repeater and driving several relays and did not use any diodes to prevent current from running in the wrong direction. So, that is probably why everything on the board was damaged.

Troubleshooting

It's alive !!!
 
Last edited:
As for programming, I thought I'd explain.
It is not as easy as you think to program. These are tiny EEPROM flat packs. About the size of your index fingers nail. I don't have an adapter to use a regular programmer so I chose to use the diagnostic board's EPROM that I can program either, -002 or -003, with. Also, these tiny chips are soldered onto the small boards. Not knowing which would be needed, it didn't make sense to pre-program them. On the board spacing there was little optional room for a select signal routing, I didn't want to add yet another trace. As it was, I didn't even run the address lines, to the chip, in chip's address order. There just wan't enough room. I didn't even put pullups or grounds on the unused addresses ( the chip had a larger address space than I needed ). I'd just tied two or three address lines to the same signal. Without doing some mapping, I realized that soldering the EEPROM would be a challenge so I soldered all the ones I shipped with the kits. I'd have a difficult time making the file in the same address order as the wiring I used. There just wasn't a lot of wiring space available on either of the two small boards and I wanted to keep the tiny foot print on.
It only took a little 6502 programming to have the KIM-1 do its own programming. One just needed to select the right switches on the diagnostic board to do the programming. The programming only took second or so. There was a small jumper loop to cut to protect from an accidental writing over the desired code ( not easily done without the magic programming sequence ).
With out knowing which chip was failing, it made sense to send the EEPROM blank.
If you had one address bit, in 6530 bad, it would have been difficult to debug without the debug board.The debug board had code specifically designed to test only one important part at a time. There was more than enough space on the EPROM for what ever needed to be programmed for the EEPROM. The first test only used the registers in the processor. The next test tested the RAM, without depending on any working RAM ( tricky to do with only the processors registers ). Next it would check the display and then the keyboard.
It wasn't until most of the board was functional before attempting to test the 6530s.
After watching your video:
The RAMs on the 6530 chips are partially mapped by the mask ROM. I'm not sure what it would do if in the wrong socket but I don't thing the RAMs were socket mapped so moving them shouldn't change the which 64 bytes of RAM each had.
One other thing, I configured the 6530-03 addressing so that it should be able to use an original program that used the interrupts. The way the 6530 and 6532 configure the interrupts are not the same. Ruud's replacement circuit ( looks like it was the base of the one you used ) doesn't do anything for that and would require some rewriting of some code.
I chose to only map the original RAM size to match the 6530s rather than uses the fully available as Ruud's does. I kind of regret it now but then I didn't want to make it more difficult to use for anyone's special setup, if they were using that other address space.

One last advantage of using my debug board is that there is lots of empty room on the EPROM to put Butterworth's KIM-1 games on. I put a couple on the EPROMs I sent with the kit.
Dwight
 
You must log in or register to reply here.
Back
Top