ColecoVision adapter for the Master System - available soon!

[Cisano]

Bravo! That's a great idea.

[b4mb00zled4g4in]

wonder if this would work with the analogue Sg with the master system adapter......

[thegoodwillgamer]

Wow!  This is awesome!  

I would absolutely buy one as my colecovisions all have some sort of issue with reliability, but my Master Systems work perfectly.

[SiRioKD]

On 10/26/2022 at 12:49 AM, Apocalypse said:

Hello.

 

I have designed an adapter to play ColecoVision games on the Master System (through the SG-1000 compatibility mode, hence slightly off colours):

 

To access the keypad maintain the PAUSE button on the console then the corresponding direction/button combination. Layout below:

 

 

Nice piece of cake! Sweet.

I wonder why if you translate port mapping on-the-fly. Am I correct?

Since Colecovision has the M1 wait state circuit as the MSX also has, could you try games like Defender which uses a very restricted timings? 

Btw, nice job.

[+Apocalypse]

22 hours ago, SiRioKD said:

Nice piece of cake! Sweet.

I wonder why if you translate port mapping on-the-fly. Am I correct?

Since Colecovision has the M1 wait state circuit as the MSX also has, could you try games like Defender which uses a very restricted timings? 

Btw, nice job.

Absolutely, everything is done on the fly (memory map, port map, bit swap on the ports).

I don't have Defender, guess I need to buy a copy.

[SearsRoebuck]

I always wondered if such a device would be possible, if this is ever somehow made commercially I would be interested.  Much as I enjoy some CV games I can't justify the space it takes up, it would be nice to have them again.

[HDTV1080P]

Real cool Sega cartridge that allows ColecoVision cartridges to be plugged in. Wish there was something like this for the 16 bit Sega Genesis. I hope this Sega Master system ColecoVision emulator is mass produced and sold one day.      

[spoonman]

This is something similar to what I've wanted for the Analogue Mega Sg for years. Would this work with the Sega SMS adapter on that? Also, would there be a way to bypass that and design a ColecoVision cart to Genesis pintpout that would trigger it to load games within the ColecoVision FPGA core on the Mega Sg? Maybe that would require an update to the CV core as well? 

 

Just a couple questions since I am interested.. 

1. Will it load the larger CV roms?

2. Will it work with SGM games?

3. Would it work while connected to a SMS to Game Gear convertor? For portable CV gaming. 

4. Do you have an ETA time or price on the converter yet?

Thanks. 

[+Apocalypse]

4 minutes ago, spoonman said:

This is something similar to what I've wanted for the Analogue Mega Sg for years. Would this work with the Sega SMS adapter on that? Also, would there be a way to bypass that and design a ColecoVision cart to Genesis pintpout that would trigger it to load games within the ColecoVision FPGA core on the Mega Sg? Maybe that would require an update to the CV core as well? 

 

Just a couple questions since I am interested.. 

1. Will it load the larger CV roms?

2. Will it work with SGM games?

3. Would it work while connected to a SMS to Game Gear convertor? For portable CV gaming. 

4. Do you have an ETA time or price on the converter yet?

Thanks. 

I doubt the Mega Sg behaves exactly like a real MS. The adapter relies on several CPU signals that are probably not implemented on the Mega Sg.

As per designing an adapter for it, the Mega Sg would need an update in order to be able to detect it and start the CV core.

 

1. What are the larger CV roms? I thought official games were capped at 32KB.

 

2. No. I don't think the SGM is an official product either. Furthermore I'm under the impression it plugs into the expansion port which the adapter lacks.

 

3. From a hardware and software point of view yes. But the extra current drawn by the adapter is too much for the GG power board.

 

4. Probably a few months (nothing never moves as fast as you expect), price around $60.

[roots.genoa]

3 hours ago, Apocalypse said:

I doubt the Mega Sg behaves exactly like a real MS.

And yet it's supposed to. A good experiment would be to try your adapter with the Master System converter for an OG Genesis. If that works, it could work on the Mega Sg as well.

[+Apocalypse]

13 hours ago, spoonman said:

This is something similar to what I've wanted for the Analogue Mega Sg for years. Would this work with the Sega SMS adapter on that? Also, would there be a way to bypass that and design a ColecoVision cart to Genesis pintpout that would trigger it to load games within the ColecoVision FPGA core on the Mega Sg? Maybe that would require an update to the CV core as well? 

 

Just a couple questions since I am interested.. 

1. Will it load the larger CV roms?

2. Will it work with SGM games?

3. Would it work while connected to a SMS to Game Gear convertor? For portable CV gaming. 

4. Do you have an ETA time or price on the converter yet?

Thanks. 

I've spent some time investigating a bit more, here are more details:

1. If those games plug into the cart slot then yes. For instance games using a bank switching method relying on accessing a specific set of addresses within the game ROM address space (e.g. FFFx) should work.

2. Can anyone clone the SGM and include it in a commercial product? Also I see the SGM sells for $90, which is 1.5 times the price of the adapter. Even if I could (space constraint inside the MS cart) and was allowed to (open source) it would more than double the targeted price of the adapter ($60).

10 hours ago, roots.genoa said:

And yet it's supposed to. A good experiment would be to try your adapter with the Master System converter for an OG Genesis. If that works, it could work on the Mega Sg as well.

It doesn't work on an OG Megadrive/Genesis for two reasons:

- the VDP doesn't support legacy (SG-1000) modes

- some vital CPU signals don't exist in MS mode

 

P.S.: Why would the Mega Sg support signals that no official piece of hardware requires?

[spoonman]

On 4/30/2023 at 4:35 PM, Apocalypse said:

I've spent some time investigating a bit more, here are more details:

1. If those games plug into the cart slot then yes. For instance games using a bank switching method relying on accessing a specific set of addresses within the game ROM address space (e.g. FFFx) should work.

2. Can anyone clone the SGM and include it in a commercial product? Also I see the SGM sells for $90, which is 1.5 times the price of the adapter. Even if I could (space constraint inside the MS cart) and was allowed to (open source) it would more than double the targeted price of the adapter ($60).

It doesn't work on an OG Megadrive/Genesis for two reasons:

- the VDP doesn't support legacy (SG-1000) modes

- some vital CPU signals don't exist in MS mode

 

P.S.: Why would the Mega Sg support signals that no official piece of hardware requires?

1. They do. The Analogue systems (Mega Sg, Super Nt, Nt, and Pocket all read the data directly off of the cartridges. Unlike something like the Retron5, which first dumps the rom and them reads it like most software based emulation. 

 

2. SGM support is included on MiSTer, Kevtris' Mega Sg ColecoVision core, and multiple CV emulators. The Mega Sg works great with all of the SGM supported games that I've tried. 

 

PS. The Mega Sg has an SG1000/SA3000 core which can output at supported resolutions. 

[+mytek]

On 5/5/2023 at 2:51 PM, spoonman said:

2. SGM support is included on MiSTer, Kevtris' Mega Sg ColecoVision core, and multiple CV emulators. The Mega Sg works great with all of the SGM supported games that I've tried.

And 100% compatibility is integrated into the soon to be released CV-NUC+ as well. People are mistaken to think this is somehow proprietary in nature. The details of which have long existed before the Colecovision ever had this capability, and before there was a module to add it.

[+Apocalypse]

On 5/10/2023 at 7:06 AM, mytek said:

 People are mistaken to think this is somehow proprietary in nature. The details of which have long existed before the Colecovision ever had this capability, and before there was a module to add it.

After reading this thread:

1) I'm now wondering if you're trying to get me under fire

2) Want to stay away from the CV community. OP was right when he said only a couple of hours was all that's needed to recreate a SGM compatible board from scratch. But maybe that's the open bitching that infuriated people...

[+mytek]

4 hours ago, Apocalypse said:

After reading this thread:

1) I'm now wondering if you're trying to get me under fire

2) Want to stay away from the CV community. OP was right when he said only a couple of hours was all that's needed to recreate a SGM compatible board from scratch. But maybe that's the open bitching that infuriated people...

 

Hmm... it certainly wasn't my intention to get under anyone's skin. I was simply pointing out that the hardware that allows games that were ported over from the MSX or SX platforms to be played on a Colecovision has either been common knowledge that dates back to the early days of ADAM (1984 Technical Manual Chapter 3 Section 2.5 Memory Map Control), or can be easily extrapolated from the MSX and MSX2 computer specification for sound generation.

 

As far as I can see there is nothing proprietary about it. And Adam already does half of it with no assistance of any external module. So basically the only thing added in that particular case would be the extra sound chip that an MSX requires -- which that has been independently created and released as a shared project at PCBway.

 

Anyway the cat's definitely out of the bag on this one, since there are no less than 3 projects either completed or nearing completion that incorporate these same MSX/ADAM features. I for one created what will become a fully open source CPLD core that gives this functionality in my soon to be released CV-NUC+ miniature Colecovision clone. And I've already pre-released the Protel CPLD schematics on AtariAge, and soon the CPLD Source and JED files will follow. I'm doing this because I feel it is the proper thing to do, and hopefully will allow others to benefit from the information. My creation was not reverse engineered from someone else's product, but instead created based upon open information that has been released to the public and is easily found via Google or on AtariAge. Point of fact is that technical information for memory and I/O register usage was openly discussed several times, and in several topics right here in the AtariAge forums. This is not how something that is considered proprietary is normally handled.

 

 @Apocalypse I'm certainly not trying to get you 'under fire' as you stated (not even sure what that exactly means). As for that other thread started by MrPix, I did find some of the conversations a bit adversarial in some regards, but that has nothing to do with anything I've said, nor is that my personal attitude. And nothing 'real' ever came out of it as was promised by the OP, so it appeared that the only purpose behind it was to stir things up. That's not what I'm trying to do.

 

EDIT: I just reread the 1st post in that MrPix thread, and I gotta say it was indeed very adversarial, to the point of saying he was going to undersell the SGM module. I should probably point out that I'm not selling anything, and in fact as far as money is concerned I'm big time in the red on my project,  and will never ever see a return, nor do I care -- this is a hobby after all

 

EDIT2: And just so everyone understands... I am not making a clone of the SGM. What I am working on will not plug into either a stock Colecovision or an ADAM, so it really shouldn't affect future sales of SGMs. In fact even if someone were to try to Frankenstein wire what I'm doing into a stock machine, I doubt if it would work out of the box properly due to incompatibility issues.

 

EDIT3: I said what I needed to say, and hopefully it helps to clear up a few things. So I apologize for taking this discussion off topic, which was not my original intention, and I will now leave the room to allow it to drift back to the previous discussions.

[+Apocalypse]

No worries at all, I was only half serious (should have used smileys?).

 

What I mean by "under fire" is after having added SGM support the community would jump down my throat for trying to make money on someone else's back (if anyone can really claim IP for such a trivial add-on).

In all honesty I felt quite uncomfortable by the strong reactions on the other thread.

 

Back to topic, thing is design is pretty much final with first units being assembled. Maybe a "pro" version in the future?

 

[RockLobster]

3 hours ago, Apocalypse said:

Back to topic, thing is design is pretty much final with first units being assembled.

Exciting news!

 

What are some of the known / outstanding issues with these first assembled units?

 

Also, do you need any testers willing to document, run test and do videos of results?

[+Apocalypse]

7 hours ago, RockLobster said:

Exciting news!

 

What are some of the known / outstanding issues with these first assembled units?

 

Also, do you need any testers willing to document, run test and do videos of results?

Listing the known issues isn't going to make it a popular product .

 

The cons:

- colours slightly off due to the Master System VDP in legacy modes

- doesn't support OG CV controllers (would require a second adapter to reroute a pin on the controller ports)

- doesn't support expansion modules

- only works with real MS consoles (more details in the posts above)

 

The pros:

- easy to get RGB (even native on French MS consoles)

- dual NTSC/PAL BIOS (maintain B2 upon boot to force the PAL BIOS)

- no delay BIOS (but with proper VRAM initialisation)

- compact solution

 

I didn't think it would become a commercial product anyway, this project was just for me to have fun and be able to play CV games down under (I've been looking for months on the local eBay for a CV with absolutely no results).

 

[RockLobster]

49 minutes ago, Apocalypse said:

Listing the known issues isn't going to make it a popular product 

Well I would say all the best stuff is when the creator is transparent and engaged!

 

49 minutes ago, Apocalypse said:

The cons:

- colours slightly off due to the Master System VDP in legacy modes

I've read that from your other posts.  Can you please post a good example of this?

 

50 minutes ago, Apocalypse said:

- doesn't support OG CV controllers (would require a second adapter to reroute a pin on the controller ports)

This is a plus in my opinion.    

 

Like many, I'm already using a modified Genesis controller for two button games along with a DB9 Y-adapter to a Super Action controller for the pad and other special games.

 

50 minutes ago, Apocalypse said:

- doesn't support expansion modules

I would expect everyone to expect this.

 

51 minutes ago, Apocalypse said:

The pros:

- easy to get RGB (even native on French MS consoles)

- dual NTSC/PAL BIOS (maintain B2 upon boot to force the PAL BIOS)

- no delay BIOS (but with proper VRAM initialisation)

- compact solution

The RGB one is probably the biggest winner.  

 

While most of us can easily play CV via a MiSTer via any analog or digital output we want, it just doesn't feel the same as taking a cartridge off the shelf and plugging it in.

55 minutes ago, Apocalypse said:

I've been looking for month on the local eBay for a CV with absolutely no results).

 

CVs are fairly common in Texas across the various marketplaces.

[+Apocalypse]

40 minutes ago, RockLobster said:

I've read that from your other posts.  Can you please post a good example of this?

There's a very good piece of information over at SMS Power (scroll down to "Master System/Mark III"):

Palette - Development - SMS Power!

41 minutes ago, RockLobster said:

CVs are fairly common in Texas across the various marketplaces.

Sure, I can find plenty of cheap units overseas but then I'm slapped with shipping costs 4 or 5 times the price of the console!

[RockLobster]

1 hour ago, Apocalypse said:

There's a very good piece of information over at SMS Power (scroll down to "Master System/Mark III"):

Palette - Development - SMS Power!

Thanks for the link.  I see that the colors are a little off.   Do you have picture of what a CV may actually look like on an SMS with your adapter so we can get an idea of what "a little off" can mean in actual practice?  thanks again 

 

[+Apocalypse]

Better, there's a video in first post.

[RockLobster]

16 minutes ago, Apocalypse said:

there's a video in first post.

Right of course.  Maybe I'm answering my own question here.

 

That is, the slight difference is hard to tell when there's not a side by side or a photo of the CV and SMS versions on the same CRT due to natural variances between setups on uncalibrated displays.

 

From someone who is only somewhat familiar with the CV ports of Donkey Kong and Tapper, they seem fine to me.  Images I pull up of each look similar too.

[+Apocalypse]

In Tapper the bartender and customers are darker (went from caucasian to mixed).

In Donkey Kong, Mario's (err... Jumpman) outfit and the barrels are supposed to be dark red, they appear as brown.

 

[RockLobster]

On 5/14/2023 at 4:27 PM, Apocalypse said:

customers are darker (went from caucasian to mixed).

🤠

 

Thanks.  Will still get one.