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JOLT replica

falter

falter

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Question - is anyone out there aware of a replica project/kit that exists for the MAI JOLT?

I know a nuts and bolts accurate JOLT replica requires a hard to find 6530-004 chip. I picked up a few of those chips and thought recreating the JOLT might be a fun project as I am steadily getting better with KiCAD - but did some googling first to see if anyone had done this already. Couldn't find any examples though.
 
The few pictures I found on internet were vague but at least I know now it is a SBC. If you have better pictures, please share them.
Then a warning: the 6530 was a Commodore made custom IC and the ones you found don't have to be ones for a JOLT. Anyway, if others are interested in your replica, I doubt you have enough 6530's to provide them with one. Therefore I point you to this 6530 replacement on my site. It has been proven beyond doubt that it works, but only for Commodore drives. Please read this document because it will show you why you probably have to change my design. Main reason: pins can have another function.

Have fun and good luck!
 
There’s not a whole lot to a JOLT so it should be easy enough to replicate, again with the obvious proviso that the rarity of the 6530-004, aka TIM, chips means that few people would be able to use an authentic replica without needing to add an adapter board similar to those used to replace the 6530’s in KIM-1’s with generic 6532 RIOTs.

(Small 6502 SBCs using far more easily found I/O chips like the 6522 VIA are a dime a dozen these days so I would certainly hesitate anyone specifically go through the trouble of building a JOLT replica unless they very specifically wanted to experience the “original” 6502 software development kit, which is what the TIM was.)
 
falter said:
Question - is anyone out there aware of a replica project/kit that exists for the MAI JOLT?

I know a nuts and bolts accurate JOLT replica requires a hard to find 6530-004 chip. I picked up a few of those chips and thought recreating the JOLT might be a fun project as I am steadily getting better with KiCAD - but did some googling first to see if anyone had done this already. Couldn't find any examples though.
Click to expand...

My answer to your question is no, I don't know of a project/replica kit that exists for the JOLT. In fact, before reading your question, I did not know anything about a JOLT. Because I have a KIM and had a C64 and learned a bit of 6502, I was interested in learning about the JOLT and the Super JOLT. You probably have seen this site and the video of the designer talking about it, but you didn't mention it in your post and others may find it as interesting as I did.

What I really found intriguing is the 6530-004 TIM. Now someone *did* make a board for that. Apparently, MOS did not, although they offered the chip and a manual. Additionally, the source code for that monitor is available. There is also the Datec 1000. I also had no idea that there were so many known 6530 variants.

I found this intriguing and started to muse about getting one of these, and rewriting the monitor for it. I even downloaded WDC tools.

Then I went back to the projects that I have already started :)
 
Yes. The genesis of doing this project was coming across some 004s on ebay for a really decent price, and then my recent experience with the retrospy 6530 replacements which worked like a charm on my KIM-1. I assume it should be possible to reprogram those as 004s if this project became something others were interested in.

I've been aware of the JOLT for years.. the name alone kind of stands out. Was really hoping to find one for my collection but in 20 years looking I've yet to see one come up. I imagine if one did I wouldn't be able to afford it anyway.
 
Knowing you, one will turn up in your extensive collection for $10 if you wait long enough!

Yes, I did know about these machines. I also came across the TIM chip (whilst perusing the 6530 ROM variants) and then found various designs using it (amongst them the JOLT).

Take note of Ruud's warning that the 6530 adaptors may not work in this scenario. The various pins of the 6530 can be programmed as well as the ROM, so (unless you check first) you may be wasting your time.

If I can find a readable JOLT schematic diagram, I will check after breakfast...

The (super) JOLT could be made using modern components of course, incorporating the TINY BASIC and Resident Assembler Package (to make a super JOLT).

You will also need to check that your 6530-004 devices are not suffering from 'bit rot' of course.

Dave
 
While I did build a TIM-1 replica, I have not found a JOLT replica project. I must admit, I did this because I was very curious if my 6530 TIM chip worked. That said, I would be interested if such a project comes up. I've been looking for a JOLT for years also. Best I could do was find a nice TIM chip but I also have the plastic version too.


TIM-1.jpg
 
I can confirm that Ruud's 6530 adapter board will NOT work in the JOLT. Mainly, for the reasons that he states - related to the programmability of certain pins during the mask process of the 6530 device.

I will have a look at the other 6530 adapter boards to see if they will.

Of course, there is nothing to stop anyone from developing a 6530 adapter board that WILL work...

Dave
 
daver2 said:
Knowing you, one will turn up in your extensive collection for $10 if you wait long enough!
Click to expand...

I think I used up my luck with my cheap Mark-8. But you never know. I think the JOLT will be harder because it just looks like a random board to the untrained/estate saling eye.. not anything approaching a computer. Probably the vast majority were tossed.

daver2 said:
Yes, I did know about these machines. I also came across the TIM chip (whilst perusing the 6530 ROM variants) and then found various designs using it (amongst them the JOLT).

Take note of Ruud's warning that the 6530 adaptors may not work in this scenario. The various pins of the 6530 can be programmed as well as the ROM, so (unless you check first) you may be wasting your time.
Click to expand...

Yeah. I emailed retrospy about their adapters and what might be involved to replicate the function of the 004. Maybe that will be too involved.

daver2 said:
If I can find a readable JOLT schematic diagram, I will check after breakfast...

The (super) JOLT could be made using modern components of course, incorporating the TINY BASIC and Resident Assembler Package (to make a super JOLT).

You will also need to check that your 6530-004 devices are not suffering from 'bit rot' of course.
Click to expand...
I bought a few NOS ones so cross fingers. They are Synertek rather than MOS too.. didn't realize Synertek was a second source for those.
 
I have had a look at the 6530-004 adapter, and it is not that more complicated than the others.

They use CS1, CS2 and /IORQ instead of PB5, PB6 and PB7 with CS1 active LOW and CS2 active HIGH.

The use of the chip select pins is documented fairly well in the manual to accomplish the various chip select functions.

1714405187225.png
(The above is for the Super JOLT manual. The JOLT manual has something similar).

Dave
 
syzygy said:
I found this intriguing and started to muse about getting one of these, and rewriting the monitor for it.
Click to expand...

I really want to say that the work to port the TIM monitor to work with a more typical modern SBC config (like, say, do its bit-bang serial console through a VIA instead of a RIOT) has already been done, but that's turning out to be a really hard thing to Google...
 
Eudimorphodon said:
I really want to say that the work to port the TIM monitor to work with a more typical modern SBC config (like, say, do its bit-bang serial console through a VIA instead of a RIOT) has already been done, but that's turning out to be a really hard thing to Google...
Click to expand...
I'm not sure what you mean by "hard thing for Google". It is pretty hard to muse about that topic, as I did, and think I would be doing it for the first time....it would, however, be the first time that *I* did it - if I were to do it :)

I did not know about all those WD boards that are 6502 "inspired" and I may still buy that $18 one for S&G. On the other hand, I was looking at the TIM-2 from that site and not only did he [Peter Renaud} build the board without the 6530-004, [used a 6532 +EPROM], but he ported the TIM monitor code as well [source is posted there]. I thought that was pretty cool.
 
So I've been up to my ears in my day job (30 days straight no days off) and have had ZERO time for vintage computers, but I did manage to scrape together a few minutes here and there to get the backside of the JOLT replica board done. However, I am running into difficulty on the top side because there are no pictures of a bare Jolt PCB, except for a very grainy one in the original ad in BYTE. Apparently the schematics were never published? I've written Ray Holt but as yet haven't had a response, and who knows if he has the info anyway. Might be a bit of an experiment, this.

kicadtrack.png
 
snuci said:
I don't recall where I got this from or if you've seen this already but maybe this will help. This is grainy but might be enough to help follow traces.
Click to expand...
Well done!! Thank you.. I can absolutely follow that. Much much much appreciated!
 
daver2 said:
I thought you had gone quiet...

Nice work on the board.

Dave
Click to expand...
Work had been quite relentless. Multiple projects that all kind of hit at the same time often going late into the evening. Crowdstrike did not help matters. Hopefully will start to calm down soon.

I wanted to push this along as learning the ins and outs of recreating PCBs helps with the more complex Sol prototype project. Plus I've always been curious about the JOLT. Apparently the Super JOLT is still produced by one of Ray Holt's former employees, for hearing testing. Haven't been able to locate him though.
 
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