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

[jhd]

I'm intrigued by the forthcoming keyboard and the prospect of "advanced applications".

 

Was this the very first video game system to claim that it could be expanded into a computer?

[BassGuitari]

Was this the very first video game system to claim that it could be expanded into a computer?

 

Eh, I wouldn't say so. The documentation with this beyond-obscure cartridge is claiming that it can transform the Studio II into a microcomputer. The console itself was never advertised to do such things. As far as I can tell, that honor goes to either the Intellivision or APF MP1000.

[Bill Loguidice]

Eh, I wouldn't say so. The documentation with this beyond-obscure cartridge is claiming that it can transform the Studio II into a microcomputer. The console itself was never advertised to do such things. As far as I can tell, that honor goes to either the Intellivision or APF MP1000.

 

I'd give it to the Bally Home Library Computer (Bally Astrocade) with its BASIC add-on (you could program from the console's keypad and load/save from tape), since that made it out before AFP's Imagination Machine add-on for the M/MP1000. However, in terms of turning into a full blown, easily recognizable computer, it's hard not to give the nod to APF. Mattel's first computer add-on didn't come out for some time after, then only in limited numbers before being replaced entirely by the ECS add-on.

[ballyalley]

Does anyone have a schematic for the Studio II? The just-posted service manual unfortunately doesn't have one, but instead has a block diagram with some notes on it.

 

I've been reading this thread on and off, and I notice that no one has followed up about the schematic. I read all the postings through today; I don't think that anyone has mentioned finding the schematic yet. However, I realize that this may have happened behind the scenes or that I may have overlooked it while skimming some of the more technical threads. So HAS the schematic for the RCA surfaced yet? If not, I'm pretty sure that I have it in a book called "How to Repair Video Games" by Robert L Goodman. The book, published in 1978, contains schematics for all sorts of Pong-type games. I THINK that it has the Studio II in there because it stands out in my memory as the only game system that actually had a CPU that was in the book.

 

I just checked around online and I didn't find a pdf of this book, but I did find mention that the book does have a schematic of the "STUDIO II BY RCA MODEL 18V100." The book is also available for about $8 plus shipping from Amazon.com, here:

 

http://www.amazon.co...t?ie=UTF8&psc=1

 

I've already looked in my garage, but I couldn't find the book. I moved back in November and I thought that I got most of my books out, but it's very possible that it's in a box that wasn't labeled properly. I can go through the trouble to look for the book some more if the schematic hasn't been found yet.

 

[@kevtris: It's interesting that I see you in this forum... and also posting over in the VideoBrain message groups. You're a busy guy!]

 

Adam

[+stupus]

I've got the book ballyalley mentioned too. I can do scans as well if it is still needed too and cant be located. Its a very nice book I would recommend it to anyone interested in this stuff.

[kevtris]

I've been reading this thread on and off, and I notice that no one has followed up about the schematic. I read all the postings through today; I don't think that anyone has mentioned finding the schematic yet. However, I realize that this may have happened behind the scenes or that I may have overlooked it while skimming some of the more technical threads. So HAS the schematic for the RCA surfaced yet? If not, I'm pretty sure that I have it in a book called "How to Repair Video Games" by Robert L Goodman. The book, published in 1978, contains schematics for all sorts of Pong-type games. I THINK that it has the Studio II in there because it stands out in my memory as the only game system that actually had a CPU that was in the book.

 

 

Nope, one didn't surface. I ended up sussing out how things were connected though, reading about the COSMAC ELF doodad, which is very very similar. The only part that I really would be interested in seeing a schematic of is the sound portion. It's just a 555 timer connected to a speaker, but it's got a wrinkle that makes the tone sound like a dying cat if it's left on for more than 50-100ms or so. There's a cap on pin 5 which makes the pitch down sweep a bit. sounds like "Beeeeoooooooo". I have the rest of the system done and functional with all existing software.

 

 

I just checked around online and I didn't find a pdf of this book, but I did find mention that the book does have a schematic of the "STUDIO II BY RCA MODEL 18V100." The book is also available for about $8 plus shipping from Amazon.com, here:

 

http://www.amazon.co...t?ie=UTF8&psc=1

 

I've already looked in my garage, but I couldn't find the book. I moved back in November and I thought that I got most of my books out, but it's very possible that it's in a box that wasn't labeled properly. I can go through the trouble to look for the book some more if the schematic hasn't been found yet.

 

[@kevtris: It's interesting that I see you in this forum... and also posting over in the VideoBrain message groups. You're a busy guy!]

 

Adam

 

 

Interesting that there IS a schematic of it kicking around then, and that such a book exists. Being published in 1978 I could see it being all pong consoles and the S2. This raises another interesting point to me- did those pong consoles fail so often that someone figured a book was a good idea? If I find a copy locally I might pick it up for the kick of seeing the guts of a bunch of old machines.

 

 

re me getting around. I sure do. I finished the Studio 2 then made the Channel F, and while I wait for things (perf board, etc) to build my own videobrain, I'm working on FPGA'izing the Emerson Arcadia 2001. Currently at the "make a CPU in verilog" stage. The S2650 CPU is a very strange beast. Should have the CPU done in a day or two, then it will be on to video and audio and then bug fixin', then done.

 

After that I should have most of the early underdog systems covered for my uber videogame console board. Next stop's probably going to be 7800 or lynx.

[+5-11under]

Nope, one didn't surface. I ended up sussing out how things were connected though, reading about the COSMAC ELF doodad, which is very very similar. The only part that I really would be interested in seeing a schematic of is the sound portion. It's just a 555 timer connected to a speaker, but it's got a wrinkle that makes the tone sound like a dying cat if it's left on for more than 50-100ms or so. There's a cap on pin 5 which makes the pitch down sweep a bit. sounds like "Beeeeoooooooo". I have the rest of the system done and functional with all existing software.

 

 

 

 

 

Interesting that there IS a schematic of it kicking around then, and that such a book exists. Being published in 1978 I could see it being all pong consoles and the S2. This raises another interesting point to me- did those pong consoles fail so often that someone figured a book was a good idea? If I find a copy locally I might pick it up for the kick of seeing the guts of a bunch of old machines.

 

 

re me getting around. I sure do. I finished the Studio 2 then made the Channel F, and while I wait for things (perf board, etc) to build my own videobrain, I'm working on FPGA'izing the Emerson Arcadia 2001. Currently at the "make a CPU in verilog" stage. The S2650 CPU is a very strange beast. Should have the CPU done in a day or two, then it will be on to video and audio and then bug fixin', then done.

 

After that I should have most of the early underdog systems covered for my uber videogame console board. Next stop's probably going to be 7800 or lynx.

Well, it's good to have you here! I've visited your old(?) website many many times over the years... very inspiring, even though you're a few levels higher than most of us, technically speaking.

[ballyalley]

Nope, one [a RCA Studio II schemaic] didn't surface. [...] The only part that I really would be interested in seeing a schematic of is the sound portion.

 

Good news and bad news. The good news is that I did find the "How to Repair Video Games" book. It was in a box, like I figured, but it was actually labeled so it wasn't as hard to find as I expected it to be. The bad news is that while most of the other systems in the book do have schematics (including some excellent ones for the Odyssey I system), the RCA Studio II does not have them. I downloaded the service manual to compare the information, and the "Video Games" book seems to have about the same information (including the block diagram in the service manual), but presented just a bit differently.

 

I'll probably scan and post the index just in case there is anything else in the book that may prove useful in the book (this will have to wait until tomorrow, at least).

 

If I find a copy locally I might pick it up for the kick of seeing the guts of a bunch of old machines.

 

The copies available on Amazon will come to just about $12, and that's including shipping. Not a bad deal... and I'd be pretty surprised if you found the book locally. However, with the number of used books that are available, it doesn't appear to be all that rare.

 

I'm working on FPGA'izing the Emerson Arcadia 2001.

 

That's a pretty neat system with lots of weird, twisted history that is scrambled all over the globe (much like the RCA Studio II's system is global, I guess).

 

After that I should have most of the early underdog systems covered for my uber videogame console board.

 

While such a system as yours can never be "complete," (there were hundreds of systems made!), I'd love to see the Bally Arcade on there. I think that qualifies as underdog. Then again, with a name like "BallyAlley," it would be a terrible if I didn't at least bring that system up at all.

 

Adam

[kevtris]

Well, it's good to have you here! I've visited your old(?) website many many times over the years... very inspiring, even though you're a few levels higher than most of us, technically speaking.

 

Thanks! I also have a blog up, which is blog.kevtris.org. I desperately need to update my website (kevtris.org) but it's such a huge time consuming task and I'm very poor at web design so it just kinda sits and languishes. Not for the lack of new stuff, but the lack of desire to do it. Be that as it may, I am going to try and keep pushing stuff to the blog since it's a bit easier to update that.

 

Good news and bad news. The good news is that I did find the "How to Repair Video Games" book. It was in a box, like I figured, but it was actually labeled so it wasn't as hard to find as I expected it to be. The bad news is that while most of the other systems in the book do have schematics (including some excellent ones for the Odyssey I system), the RCA Studio II does not have them. I downloaded the service manual to compare the information, and the "Video Games" book seems to have about the same information (including the block diagram in the service manual), but presented just a bit differently.

 

I'll probably scan and post the index just in case there is anything else in the book that may prove useful in the book (this will have to wait until tomorrow, at least).

 

Thanks for checking. I bet they just got a bunch of the service manuals from the various manufacturers and threw them together. Though I think RCA deliberately didn't give the schematics out for some reason. Either they thought "microcomputer repair" would be too tough for traditional TV repair men, or maybe they figured it'd give too much valuable information away to competitors (not likely), or that there just wasn't a schematic available in the first place. I'm very guilty of the latter- I make a PCB for something and don't have a schematic of how it connects- just a block diagram at best, and a few mini schematics of various parts.

 

 

While such a system as yours can never be "complete," (there were hundreds of systems made!), I'd love to see the Bally Arcade on there. I think that qualifies as underdog. Then again, with a name like "BallyAlley," it would be a terrible if I didn't at least bring that system up at all.

 

Adam

 

Yeah I was thinking about that a few minutes after I hit "post". I was going to add that too since I have a perfect cycle accurate Z80 already done (needed that for the sms/coleco/gg). Slapping on the bally frame buffer and "magic" controller chip didn't look too hard, I read the documentation awhile back. I thought it was pretty interesting, all told. I guess sound is still a minor issue with emulation?

 

Re the Arcadia 2001, I almost need to buy some of the chips (or get one of the systems) in to do testing, because the documentation I found is quite lacking. While I have the documentation on the various chips, the documentation is extremely poor. Another job for the logic analyzer I think.

[paulrobson]

I've been reading this thread on and off, and I notice that no one has followed up about the schematic.

The schematic is fairly self explanatory ; if you cross the Cosmac Elf schematic with my technical information and the online schematic of the switch box that exists somewhere, that's basically it

[paulrobson]

Nope, one didn't surface. I ended up sussing out how things were connected though, reading about the COSMAC ELF doodad, which is very very similar. The only part that I really would be interested in seeing a schematic of is the sound portion. It's just a 555 timer connected to a speaker, but it's got a wrinkle that makes the tone sound like a dying cat if it's left on for more than 50-100ms or so. There's a cap on pin 5 which makes the pitch down sweep a bit. sounds like "Beeeeoooooooo". I have the rest of the system done and functional with all existing software.

 

I've got a rebuild of this on my desk as I write. It is a standard 555 astable circuit with the upper resistor 400k (2 x 200k in mine) and the lower resistor 480k (470k in mine). I measured these (I think) so they probably are 390k and 470k resistors as 400/480 are not standard sizes. The capacitor is 2.2nf. I don't know if there's a speaker driver on the output, this circuit is sufficient to drive a Piezo Buzzer.

 

The 'wrinkle' is that the cap from 5 to ground is a 10uf electrolytic not a 10nf poly cap as one would normally use. This makes it sound like a foghorn with a rapid pitch decay over about 1/4 second or so.

 

Everything else is as per a standard 555 astable circuit.

 

It does mean you can get a couple of different tones out of it.

[ballyalley]

Thanks for checking. I bet they just got a bunch of the service manuals from the various manufacturers and threw them together.

 

I completely agree. That book certainly has got a lot of material packed into a small space.

 

[Maybe RCA] thought "microcomputer repair" would be too tough for traditional TV repair men

 

From what I've read, computer repair WAS too tough for the average TV repair person. It was the skill set that lacked (not the intelligence)-- these folks didn't have the digital knowledge required. Why should they? Most of these techs (nearly all of them, really) were pure analog guys. They didn't need to know how to troubleshoot a computer. Also, there was a severe lack of documentation in the beginning of the home computer age, not just for those who wanted to repair the systems, but for those that also wanted to use them to the best of their ability. Forget about hacking. Those that used the Studio II thought of it as nothing more than an appliance that you hooked up to your TV. The "How to Repair Video Games" book was probably a valuable resource. Though, as Kevin already mentioned, how many of those Pong clones were going bad? It's not like they were used year in and year out for years on end. Those consoles really WERE a fad. The systems did reside in closets and garages only to be dragged out of them years later for yard sales, donation and the dump.

 

I was going to add [the Bally Arcade / Astrocade] too since I have a perfect cycle accurate Z80 already done (needed that for the sms/coleco/gg). Slapping on the bally frame buffer and "magic" controller chip didn't look too hard

 

You make electronics seem so easy. I remember reading your website in the late nineties, around the time that you were hacking the Colecovision games (I bought those carts back then-- though I sold them in the mid-2000's when my second, or maybe third, Colecovision died). You go after something and it was in your hands. I recall that when you programmed Kevtris that you didn't use sprites because you didn't know that the graphics chip was also used in the MSX computers. It is very likely that that sort of knowledge was much easier to find than in 1978. Imagine what those TV Techs were going through with the first Atari game that came through their front door.

 

As an aside, Kevin. In the late 1990's your website had a small blinking LED project, which was pretty neat as it didn't use a battery-- just solar panel and a cap. Very simple, yet it ran 24-hours a day (yes, folks, even in the dark when the cap supplied the voltage required for the small amount of energy required by the LED). How long did that project last before it finally stopped blinking-- or do you still have it blinking away someplace?

 

I read the documentation [on the Baly Arcade] awhile back. I thought it was pretty interesting, all told.

 

Yeah, most everything that you need is up there on my Bally Arcade website:

 

http://www.ballyalley.com

 

[You mentioned that your website needs updating... mine sure does... even my wife makes fun of the way it looks. Sob.]

 

The Bally Arcade has been done in FPGA before (including hi-res mode-- you know, the mode that the arcade versions of Wizard of Wor and Gorf used). I know for certain that at the time that the FPGA Bally was created (2006), that it required more tinkering to understand the Bally Arcade. I don't think that the FPGA system supports extra RAM, which third-party products did support and that is required to use all of the released cartridges. Surely the other FPGA system doesn't support the Intel I/O chip that is used for tape/serial/pareallel I/O by the Blue RAM. Surely this is popular enough to be supported?

 

I know that you don't reuse other people's code, but you may be able to get some information... although you seem like the guy that only trust's your own investigation skills. The main page for that FPGA site is:

 

http://www.fpgaarcade.com/

 

Kevin (or others?), if you want to talk more about the Bally Arcade, why not drop by the Astrocade discussion group, here:

 

http://tech.groups.y...oup/ballyalley/

 

I guess sound is still a minor issue with [bally Arcade] emulation?

 

Yes, I guess there are minor issues with the sound... although most, or nearly all of those issues have been stamped out. As for me though, I can't say that I notice any sound issues when using MESS. What I do notice is that the MESS emulation had to be given a quick hack so that it would work with BASIC.

 

I'm getting WAY off of the RCA Studio II topic. Sorry about that. It's not often that I hear someone with Kevin's ability and reputation say that he wants to create an FPGA Bally system. Even, as he has said it, just about in passing.

 

Today I'll upload (to this thread) the two table of contents pages for "How to Repair Video Games." Maybe there is more RCA-related information in there then I think?

 

What is the best way to upload files to AtariAge? What I do now is put them on my own website and then link to them. Surely there must be an easier (and better) way to do this.

 

Adam

[ekeefe]

Hello,

 

I joined this forum specifically because of this thread. I am very involved with the 1802 and have been since I was a kid. I have done a lot of work with the COSMAC Elf and the RCA VIP. I have built a bunch of different systems. You can see some of the things I have done here:

 

http://www.cosmacvip.com

 

I am also interested in a multi-cart when they become available.

 

I would like to share some information I have on the RCA Studio II.

 

I had a non-working unit so I decided to remove all the components from the PCB and scan both sides. From this I drew up a schematic of the board. I then used an ohm meter to verify my drawing.

 

I redesigned the circuit and built my own Studio II. It is sort of a multi-cart version. I have a little 16-position rotary switch that selects which "Cart" to run. It is limited to 1K cartridges however. It has 32K of ROM and 32K of RAM. I did this only because I use these chips quite often and have a bunch of them. My board does not have an RF section, only a video out.

 

Here are huge (20meg) images of the Studio II PCB I scanned:

 

http://www.avionline..._II_PCB_TOP.jpg

http://www.avionline..._PCB_BOTTOM.jpg

 

Here is the schematic I drew, with no RF section:

 

http://www.avionline...I_Schematic.pdf

 

Here is the service manual for the Studio II (found this one on the net):

 

http://www.avionline...vice_Manual.pdf

 

And finally, here is a picture of the Studio II I built:

 

http://www.avionline...I_Studio_II.jpg

 

I hope you find this helpful. If you have questions, please ask.

 

ED

[ballyalley]

I've done a bit of scanning from Robert Goodman's 1978 book, "How to Repair Video Games." Here is the two-page table of contents, plus the cover (colors inverted). I scanned it so that you can determine if you want to purchase the book, as I don't plan to scan anything else from it. This document was scanned in grayscale at 300dpi and then converted to B&W, so the file size is small:

 

http://www.ballyalle...8V100)(B-W).pdf

 

Next up is the fourth chapter called "Studio II by RCA Model 18V100." This seems to have all the related material from the RCA Studio II Service Manual, but it's not an exact duplicate. Maybe it's a later (or earlier?) version of the manual, or perhaps the author just cut and pasted the Service Manual to suit his needs. I don't know. Here is chapter 4, scanned in grayscale at 300dpi and then given an index so that you can view the it easier (and so that Google gets more information out of it). I prefer this version, but it's rather large at about 5.7MB for a 14-page document:

 

http://www.ballyalle...del 18V100).pdf

 

Here is the same 14-page chapter, scanned in grayscale, cleaned up, and then converted to B&W so that the file size is smaller. This document is about 1MB, but it lacks the index that I created from the preferred grayscale version. You can get the B&W version here:

 

http://www.ballyalle...8V100)(B-W).pdf

 

These files are in a temp area of my website. I'll remove them sooner or later (in a week or two, I suppose). I'd appreciate it if someone could host these files on an RCA Studio II website (or elsewhere), so that people who are interested are more likely to run into them

 

Have fun with this stuff-- it's neat!

 

Adam

[kevtris]

I've got a rebuild of this on my desk as I write. It is a standard 555 astable circuit with the upper resistor 400k (2 x 200k in mine) and the lower resistor 480k (470k in mine). I measured these (I think) so they probably are 390k and 470k resistors as 400/480 are not standard sizes. The capacitor is 2.2nf. I don't know if there's a speaker driver on the output, this circuit is sufficient to drive a Piezo Buzzer.

 

Thanks for that information! You guessed right on the resistors, going by the schematic that was just posted.

 

Hello,

 

I would like to share some information I have on the RCA Studio II.

 

I had a non-working unit so I decided to remove all the components from the PCB and scan both sides. From this I drew up a schematic of the board. I then used an ohm meter to verify my drawing.

 

I redesigned the circuit and built my own Studio II. It is sort of a multi-cart version. I have a little 16-position rotary switch that selects which "Cart" to run. It is limited to 1K cartridges however. It has 32K of ROM and 32K of RAM. I did this only because I use these chips quite often and have a bunch of them. My board does not have an RF section, only a video out.

 

 

 

A+ job on recreating the S2! I am going to do this for the Video Brain and the Arcadia 2001 since both are quite rare and expensive, not to mention cartridge availability issues.

As to the S2, I was curious on a few of the details of how the chips were connected. I did a few minor modifications to put my FPGA in line with the actual circuit. Thanks for posting the schematics. it was helpful.

[kevtris]

 

You make electronics seem so easy. I remember reading your website in the late nineties, around the time that you were hacking the Colecovision games (I bought those carts back then-- though I sold them in the mid-2000's when my second, or maybe third, Colecovision died). You go after something and it was in your hands. I recall that when you programmed Kevtris that you didn't use sprites because you didn't know that the graphics chip was also used in the MSX computers. It is very likely that that sort of knowledge was much easier to find than in 1978. Imagine what those TV Techs were going through with the first Atari game that came through their front door.

 

 

Yeah, I had issues finding information back in 1995 on the internet about it. I am not sure why it was so hard but I never did find a datasheet or much else. I actually reverse engineered how the coleco worked enough to program the game. I had no datasheets or other information to help me at the time. These days it's so much easier since information flows faster.

 

Back when I was a kid in the 80's, getting information about electronics was extremely tough. My only conduit was a few books and magazines, and even the magazines weren't all that great. They would always give you that off-hand one liner that used to annoy me greatly. "x is beyond the scope of this article. if you want more information, go to your nearest technical library". I always was bemused about that; living in the sticks outside a small town, there were no such things as "technical libraries". When I started getting information from the internet, things accelerated into high gear and my abilities took off. (I have no "formal" college training in electronics or programming)

 

 

As an aside, Kevin. In the late 1990's your website had a small blinking LED project, which was pretty neat as it didn't use a battery-- just solar panel and a cap. Very simple, yet it ran 24-hours a day (yes, folks, even in the dark when the cap supplied the voltage required for the small amount of energy required by the LED). How long did that project last before it finally stopped blinking-- or do you still have it blinking away someplace?

 

Yes. it's still blinking away! I made that thing in 1994 or so and almost 20 years later it's still flashing away.

 

 

The Bally Arcade has been done in FPGA before (including hi-res mode-- you know, the mode that the arcade versions of Wizard of Wor and Gorf used). I know for certain that at the time that the FPGA Bally was created (2006), that it required more tinkering to understand the Bally Arcade. I don't think that the FPGA system supports extra RAM, which third-party products did support and that is required to use all of the released cartridges. Surely the other FPGA system doesn't support the Intel I/O chip that is used for tape/serial/pareallel I/O by the Blue RAM. Surely this is popular enough to be supported?

 

I know that you don't reuse other people's code, but you may be able to get some information... although you seem like the guy that only trust's your own investigation skills. The main page for that FPGA site is:

 

http://www.fpgaarcade.com/

 

 

Yeah I figured it had been. I was going to have high rez mode too, since I got all the RAM in the world on my board. You are right though, I tend to like to do it all myself. I'm not trying to be stuck up about it, but the main reason I am doing this is for fun and it's no fun if all the work's already been done for you. I like the investigation, implementation and final product and being able to say I did it all myself. The other reason is I tend to be extremely careful about it and leave no stone unturned; I want my simulations to be as close to the "real thing" as possible including internal bus and timing waveforms. Maybe a bit obsessive-compulsive but I strive for extreme accuracy.

 

 

Yes, I guess there are minor issues with the sound... although most, or nearly all of those issues have been stamped out. As for me though, I can't say that I notice any sound issues when using MESS. What I do notice is that the MESS emulation had to be given a quick hack so that it would work with BASIC.

 

I'm getting WAY off of the RCA Studio II topic. Sorry about that. It's not often that I hear someone with Kevin's ability and reputation say that he wants to create an FPGA Bally system. Even, as he has said it, just about in passing.

 

Today I'll upload (to this thread) the two table of contents pages for "How to Repair Video Games." Maybe there is more RCA-related information in there then I think?

 

What is the best way to upload files to AtariAge? What I do now is put them on my own website and then link to them. Surely there must be an easier (and better) way to do this.

 

Adam

 

Aaah, good old sound. Always the last thing that gets emulated accurately. I am not sure why this is, other than it can be somewhat difficult to debug audio vs. video, though my usual method is recording the waveform and seeing what it looks like to suss out what happens. I tend to be very sensitive to bad sound on emulators, and can hear subtle issues and inaccuracies and it is pretty distracting. For the Bally I am going to poke around with an actual console maybe and work my magic on its sound chip like I did with the Odyssey^2.

 

Thanks for the pdfs, gonna poke thru them.

 

Re: off topic, sorry 'bout that, I will start another post maybe in the hardware forum about bally stuff when I get there or similar, hehe.

[jdrose]

"The book, published in 1978, contains schematics for all sorts of Pong-type games."

 

With all due respect, the Studio II was not a "Pong Type" game. It did not rely on the discrete logic chips of pong consoles. The Studio II was a full computer architecture based console running an 1802 microprocessor executing programs stored in interchangeable ROM cartridges.

[fauxscot]

 

Thanks y-bot! I appreciate the photos a lot.

Edited April 12, 2013 by fauxscot

[fauxscot]

Nope, one didn't surface. I ended up sussing out how things were connected though, reading about the COSMAC ELF doodad, which is very very similar. The only part that I really would be interested in seeing a schematic of is the sound portion. It's just a 555 timer connected to a speaker, but it's got a wrinkle that makes the tone sound like a dying cat if it's left on for more than 50-100ms or so. There's a cap on pin 5 which makes the pitch down sweep a bit. sounds like "Beeeeoooooooo". I have the rest of the system done and functional with all existing software.

 

 

The diode on the 555 circuit is used to provide that non-linearity in the beep, FYI. It was a feature, not a problem!

[fauxscot]

I've done a bit of scanning from Robert Goodman's 1978 book, "How to Repair Video Games." Here is the two-page table of contents, plus the cover (colors inverted). I scanned it so that you can determine if you want to purchase the book, as I don't plan to scan anything else from it. This document was scanned in grayscale at 300dpi and then converted to B&W, so the file size is small:

 

http://www.ballyalle...8V100)(B-W).pdf

 

Next up is the fourth chapter called "Studio II by RCA Model 18V100." This seems to have all the related material from the RCA Studio II Service Manual, but it's not an exact duplicate. Maybe it's a later (or earlier?) version of the manual, or perhaps the author just cut and pasted the Service Manual to suit his needs. I don't know. Here is chapter 4, scanned in grayscale at 300dpi and then given an index so that you can view the it easier (and so that Google gets more information out of it). I prefer this version, but it's rather large at about 5.7MB for a 14-page document:

 

http://www.ballyalle...del 18V100).pdf

 

Here is the same 14-page chapter, scanned in grayscale, cleaned up, and then converted to B&W so that the file size is smaller. This document is about 1MB, but it lacks the index that I created from the preferred grayscale version. You can get the B&W version here:

 

http://www.ballyalle...8V100)(B-W).pdf

 

These files are in a temp area of my website. I'll remove them sooner or later (in a week or two, I suppose). I'd appreciate it if someone could host these files on an RCA Studio II website (or elsewhere), so that people who are interested are more likely to run into them

 

Have fun with this stuff-- it's neat!

 

Adam

 

You are the man! Thanks. Good job on the scans, too.

[TLD1985]

I wonder how many test/diagnostic carts actually do still survive..

 

same goes for the store demo carts.

[ballyalley]

With all due respect, the Studio II was not a "Pong Type" game. It did not rely on the discrete logic chips of pong consoles. The Studio II was a full computer architecture based console running an 1802 microprocessor executing programs stored in interchangeable ROM cartridges.

 

Understood. My first posting about this book (a day earlier) does clarify that the book has the Studio II, which is the only system that uses a CPU. I was describing the rest of the book, not chapter which I had scanned. Sorry for the confusion.

 

Adam

[ballyalley]

Thanks [for the scans of chapter 4]. Good job on the scans, too.

 

Sure. No trouble. I've been working on getting scans that look good for quite a few years now. I've learned that it is much faster just to scan it and forget it, but I've regretted some scans that I've made that way. Some scans turn out to be the only ones available and it's not very useful to me (or others) when some of the pages are hard to read. Taking a bit of extra time to make a quality scan, clean it up and then to add an index is very helpful. Not only to myself, but to others who are using the scan.

 

Adam

[paulrobson]

I've now finished my RCAS2 Scramble - see below. The download also contains all the other homebrews, and I've modified the 1k+ carts to map to $C00-$FFF, and to build with asmx.

 

http://www.robsons.org.uk/homebrew.zip

 

[slydc]

OMG!! I am sssoooo FUDGING impressed!

 

And only in 1.7K...that's unbeleivable! Same goes as all your others homebrews.

 

Seems like you did the same thing as all the European Studio II clones BIOS, the Blackjack game is also mapped

to $C00-$FFF. Do you have other Studio II brews up your sleeve ?

 

So major kudos to all your Studio II brews and your Unisonic Champion 2711 emulator.

 

--- Sly DC ---

Edited April 13, 2013 by slydc