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RCA Studio II GOLD MINE! An interview with the Studio 2 Production Manager!

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Back and working on the multi-cart. I have a trick for making the S2 reset button dual purpose.

 

Proto with a few games for testing should be a few weeks.

 

Woot.

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I know a few people have posted saying they are having a hard time finding a working console. I have a nice spare console with a beat up box, tested and working, plus every cart boxed (missing two manuals.). I was asking $300 for the but I'm willing to separate or negotiate on the lot.

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Rom/Cart Status tables:

 

rcadump.jpg

 

Notes:

 

0)I noticed the typo.. I'm just being lazy right now..

1)It is likely that the rom files on the other clone systems are identical to the MPT-02 carts, however would be a good idea to do a dump of them to confirm this.

2a)For multi-cart purposes it's probably not needed to include the MPT-02 games that are identical to the Studio II.

2b)For rom preservation purposes it is still important to dump all the MPT-02 games as their roms files are different. (and maybe some do have colour programmed in?)

3)Unsure if Visicom games can be dumped in the same way or are compatible.

4)Grandpack is a mixture of the 4 BIOS games found on clone systems... can this be dumped the same way ? and would there be a need to include it on the multicart?

Edited by TLD1985

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Back and working on the multi-cart. I have a trick for making the S2 reset button dual purpose.

 

Proto with a few games for testing should be a few weeks.

 

Woot.

 

Are you only supporting 1k Games ?

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Are you only supporting 1k Games ?

 

hi paul.... i have been meaning to drop you an email and introduce myself. you are an amazing repository of info on this thing and i am duly impressed!

 

i'm in the schematic capture stage of this multicard thing and it is based on 1k pages. i thought that would be liberal and excessive for the smaller carts. what do you think? i suppose I could do a 2k page and bump the EPROM up to a 64K x 8. (I have a bunch of 32k x 8 chips and that's one consideration, but regardless, the concept it identical except for a few wires and some additional combinatorial logic.) Would 2k be enough?

 

the scheme i have uses memory reads at 80xx to select pages. once selected, a short reset puts the unit into the game ROM and a long reset puts the unit back into the selection mode. if i understand the software properly, this shouldn't be difficult to do, but that's what i always say about software and i am always wrong.

 

i am very tempted to buy an 1802 pod for my old fluke 9010 troubleshooter. might be handy for hardware wakeup but the last one i saw was $200 and i am a cheap bastrd.

 

any suggestions greatly appreciated and this is the best time to get them in, as you know, before the concrete sets up.

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i'm in the schematic capture stage of this multicard thing and it is based on 1k pages. i thought that would be liberal and excessive for the smaller carts. what do you think? i suppose I could do a 2k page and bump the EPROM up to a 64K x 8. (I have a bunch of 32k x 8 chips and that's one consideration, but regardless, the concept it identical except for a few wires and some additional combinatorial logic.) Would 2k be enough?

 

the scheme i have uses memory reads at 80xx to select pages. once selected, a short reset puts the unit into the game ROM and a long reset puts the unit back into the selection mode. if i understand the software properly, this shouldn't be difficult to do, but that's what i always say about software and i am always wrong.

 

I think knowing that much about this thing is a sign of being a bit mad :)

 

Technically, no it doesn't. I presume you are mapping the 1k of Memory in at 0400-07FF. All the homebrews I've written take an extra 512 bytes between 0A00 and 0BFF. It would be trivial to change them to run anywhere in ROM, on a 2k mapping the easiest thing would be 0C00-0FFF. (In a classical S2 design it doesn't matter because of the self-mapping ROM images). This also offers compatibility with the Victory and MPT-02 I think - one does not use it, and the other has ROM there which would be disabled by the usual mechanism (the disable line back to the RCAS2)

 

In theory undiscovered carts could fit literally anywhere in the memory map even where the RAM is (accessing the RAM elsewhere). However it is almost 100% certain that they will all be 1k or less and be put in 400-7FF :) Bingo might, just might have its ROM stuck in at 400-5FF and A00-BFF but it almost certainly won't.

 

Here's a suggestion.

 

If you use 2k for every cartridge you are wasting space. Most cartridges are 1k. I'm working on another Homebrew (Scramble) which will be <2k. I can't see anyone having the patience to write more than 2k of ROM really. The graphics aren't worth it. You could write a Zelda a la Pacman but it would look horrible :)

 

Presumably you are decoding for x400-x7FF e.g. you are decoding on A11 = 0 and A10 = 1 - this selects your ROM and maps it in when any sixteen bit address matches xxxx 01xx xxxx xxxx and maps out the built in RAM mirror at C00-DFF (so you'd have to use ROMDIS *and* ROMCS)

 

If you extended it slightly, so you decode only on A10 = 1 - so your ROM maps into xxxx x1xx xxxx xxxx then it will map the ROM in x400-x7FF and xC00-xFFF - so there will be 32 mirrors throughout the 64k address space, none of which matter.

 

If you then take the A11 line - which is 0 for x400-x7ff and 1 for xC00-xFFF and OR that with A10 of the 32k ROM you are using for the mirroring then this will force every even page to be mapped to C00-CFF. (A0-A9 select the 1k ROM as normal - presumably A10-A14 are latched on the read from 80xx but tbh it wouldn't matter if it was 8000-FFFF i.e. you just used AD15 of the 1802)

 

This would I think give you the following mapping, dividing the 32k EPROM into 1k pages

 

A10-A14 (EPROM) 400-7FF C00-FFF

=============== ======= =======

0 0 1

1 1 1

2 2 3

3 3 3

4 4 5

5 5 5

6 6 7

7 7 7

 

and so on. Without the OR tweak it would just match each page to the selected page. With it it forces the page that is mapped to C00-FFF to be an odd numbered page (because A10 of the 32k ROM is forced to '1' by A11 from the 1802).

 

With this arrangement you won't waste any pages. 1k games can go in any of the 32k pages. 2k games only need to go in even numbered pages so their code is in the two chunks. Code is mapped to C00-FFF but that is an irrelevance. The only catch is that some of the paging options will not run a game - in the example above if you put invaders in page 6 and 7 it will map the first 1k to 400-7FF and the second 1k to C00-FFF when selected, but if you select page 7 it puts the second half of the code in both spaces, which will not work.

 

You are still wasting cartridge space for 512 byte ROMs. But other than that this arrangement should work on the Victory and MPT02 if (1) Marcel's documentation is right and (2) there isn't any BIOS code in C00-FFF in the Victory, which has ROM at C00-FFF but only for its built in games, which doesn't matter if you are running a cartridge game.

 

I'd make sure it works first though - this is a theoretical design ;) I never built the version on my old website, though it should work in theory.

Edited by paulrobson
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fauxscot are you ready to accept carts for dumping?

 

not quite yet. i have two consoles to troubleshoot and a few carts already for dumping and testing, so that's enough for the moment. the design I am working on will work for many if it works for two, and the only fly in the ointment is 2k games per Paul R, above. I am thinking about that now. Once it works in prototype, I'll play with the files I have that are available, and at some point, will deal with the additional undumped titles.

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Anyone know who bought this board from member Tempest? I'd love to get my hands on it briefly, and/or get a pix of the other side. It's some sort of Studio 2 programming board, nicely done.

 

rca_programming_cart.jpg

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No kidding- this is only the third copy of ANY of the Star Wars Game(s) I've seen on Ebay in the past 6 years. The first was a loose tan-colored cart back around 09 that went for just over 100, they also had an identical Concentration Match cart. The next copy was the CIB Sheen copy I won with my final sniping bid of $150 when it was at 2.5 seconds. The end price was $145 US dollars, and that auction ended at a terrible time on a Wednesday. I think the seller is the same one who is selling the current loose cart- it might well be worthwhile to drop him a line and ask if he has any other Studio II clone carts.

 

There have been several copies. I have one, and I certainly didn't pay over $100 for it. I don't think it's particularly rare, but given the inadvertent name, I think it gets more attention than it's worth. Obviously not an attempt to capture the Star Wars sage.

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Rom/Cart Status tables:

 

rcadump.jpg

 

 

Unfortunately I have several things on the lists but I have no access to my collection at this time.

 

First, I have an assembler cartridge that was homebrewed not long ago and was sold on eBay by the guy who made them. He even had a makeshift overlay. Don't tell me I'm the only with this item here? I sent him an email, and if he doesn't respond, I can PM his name if anyone wants to try to track him down. I would love to see this on the multicart if he approves of it. It was called the "Studio II Programming Aid". I never messed around with it enough to describe it's functionality in detail.

 

I have Visicom 110, 130, 140 and 160. I have not found certain proof of the existence of the other two carts. Again, in storage.

 

I also have two versions of Star Wars, which I only indicated MG-203 and "05" in my inventory. I think I couldn't confirm the system for those. I also have a Concentration Match MG-202, Speedway/Tag MG-211 and Pinball "07". All in storage. Would be happy to have them dumped if it comes to that, but I won't be into my storage for a long time, unfortunately. The end of the year at the earliest.

 

Sorry to be of almost no use!

 

My comments about a multicart to follow.

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Of course, a multicart would be awesome. Sign me up.

 

The cheaper the better. However, I know these projects cost money. The higher you price these items at, the slower they sell and the fewer that will sell. I believe that rather than giving a good amount of cash to Kickstarter for a project that could get 50 supporters on a good day, it would be worthwhile just to advertise in the major forums and patiently sell your production run over the course of a few years. And keep one available at a fixed price on eBay regularly or occasionally. You can price in the additional cost of selling through eBay. eBay has great exposure. I'm happy to stock carts in my store and help sell/ship them if need be.

 

My feeling is that @fauxscot should aim for the $75 price point, including the cost of materials. It sounds likely that these will require sacrificing an original cartridge, which will limit production and create a higher cost. If you (@fauxscot) can get it to $50, that's fantastic, but don't sacrifice the cost of your time, which I'm sure you are well aware of, and could never be reimbursed at what you are worth by the project. You may quickly realize that even if you can sell 50 carts, these projects are more of a labor of love. Almost no hobbyists can make their money back from these projects, when you consider the time invested. If it had to go to $100, you would still sell many carts in the short term, and fewer long term. Well over $100 and you're getting towards a fetish item with an even smaller market. Still, I'd buy one.

 

My sense is that at $75, you will be able to sell 25 cartridges immediately, 20-25 in the following 2-3 months and then probably 1 a month on average for several years. I think the market could tolerate 100, but it would take several years to distribute those. But would you even want to spend the time building that many carts? Most people with production runs that large have their items fabricated or have a less labor intensive system in place. And if you want to build 50 carts with the soldering it sounds like you'd need to do, you could write a book called "Zen and the art of cartridge assembly" after you're done.

 

Your (@fauxscot) passion for the system is obvious and we collectors and classic gamers are fed by it. It's truly inspiring to us and very exciting. Thanks for getting involved here and thanks for being part of the resurrection of this system. The history you provide is priceless.

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Unfortunately I have several things on the lists but I have no access to my collection at this time.

 

First, I have an assembler cartridge that was homebrewed not long ago and was sold on eBay by the guy who made them. He even had a makeshift overlay. Don't tell me I'm the only with this item here? I sent him an email, and if he doesn't respond, I can PM his name if anyone wants to try to track him down. I would love to see this on the multicart if he approves of it. It was called the "Studio II Programming Aid". I never messed around with it enough to describe it's functionality in detail.

 

I have Visicom 110, 130, 140 and 160. I have not found certain proof of the existence of the other two carts. Again, in storage.

 

I also have two versions of Star Wars, which I only indicated MG-203 and "05" in my inventory. I think I couldn't confirm the system for those. I also have a Concentration Match MG-202, Speedway/Tag MG-211 and Pinball "07". All in storage. Would be happy to have them dumped if it comes to that, but I won't be into my storage for a long time, unfortunately. The end of the year at the earliest.

 

Sorry to be of almost no use!

 

My comments about a multicart to follow.

 

 

Well good to know we do have a potential source for some of the missing Japanese carts. :)

 

The MG-2xx carts would be an MPT-02 clone system

The other carts you have I will guess are actually M1200-xx carts from a Sheen M1200 or Conic M1200

Fortunately we have copies of those for dumping, unless of course it's found that the sheen roms are slightly different.. but I doubt it. Would be nice to have scans of the Sheen carts/boxes/etc for achieving. :)

 

 

The only other real carts that are missing are the extremely rare and obscure... demo carts and testing carts seem to only be 1-3 in existence from what I have heard.

Edited by TLD1985

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I have it and I think I mentioned it somewhere earlier in this epic thread!

 

any chance you'd shoot a good pix of the back side and post it and/or email it? i'd love to see if it matches the program card schematic i have. pretty cool. have you used it? does it work? this thread is getting so long it might take me a while to find your mention of it, but i do appreciate your mentioning that you have it.

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For anyone interested, I have been troubleshooting 4 units from two members to get re-acquainted with this thing. One was simple in that it turned out to be misadjusted RF oscillators but otherwise worked OK. Another one was a display chip failure... one bad data line. it was fixed with cannibalizing. The remaining two have 800-8ff RAM problems, but their 900-9ff RAM is good, meaning one of them can be recovered. So 3 for 4... not bad for an old man.

 

I obtained an 1802 pod for a Fluke 9010a micro system troubleshooter and that is what I've been using to test these, as well as normal test techniques based on knowledge of how the unit works. I built a ROM dumper and am working on the multi-card, though I am still struggling with a few architectural decisions before I commit to an approach. This has more to do with part availability than anything, and with consolidating all of those cartridges into one big ass cart, if possible. Stil a few days away from deciding on the best approach, but there are many alternatives.

 

Other thing in the mix include finding the thread on the 1861 video chip replacement using PALs, which I think I will do while I'm at it. (I have a programmer for them and the JED files.) I am interested in this approach particularly for legacy stuff like this thing.

 

That's the news. More as it happens.

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any chance you'd shoot a good pix of the back side and post it and/or email it? i'd love to see if it matches the program card schematic i have. pretty cool. have you used it? does it work? this thread is getting so long it might take me a while to find your mention of it, but i do appreciate your mentioning that you have it.

 

I'll try and get some pics tonight. From what I've read you need a system with upgraded memory to use it. The newsletters have plans for this I believe. Way over my head though.

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I'll try and get some pics tonight. From what I've read you need a system with upgraded memory to use it. The newsletters have plans for this I believe. Way over my head though.

Looks similar to my design, a latch to latch TPA, some address logic decoding and a more standard ROM. You don't need anything else to work, as you can use the RAM from $800-$8FF except for the around $8CE where there are three timer bytes - but then you could replace the video driver. Hard work though.

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I'm glad someone is finally looking at that programming cart. It was sitting in my box for years and I never touched it.

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