TG16/PCE converter

[Ninja16608]

Hey all,

    Just wanted to share a little something I have been working on. After looking around and finding converters going for nutso prices and finding and following Chops converters, and seeing all the other variations out there from the diving board (made me cringe) and seeing home brew PCI bus converters. I thought about all the things that can go wrong with the different types and wanted to come up with a solution for it. The diving board made me cringe due to the length of it and how much hung over the front of the system, one small mistake and its toast. I have even see scary images of people crossing contacts with foil and other connective materials and sticking them into their systems (iirc one of chops first was a flat ribbon cable). I have already begun the process of working a board up but in the middle had a thought. I want to make this converter work for both systems and I have seen some out there that have a switch to go between the two. Now I'm no engineer but the design works for me and my work for others. My question is, are there chips out there with some kind of switching program on them that will in effect re route the traces internally and out put to the right channels and how much more difficult would this make the board design?

I have some renders of early works I did in 3ds Max, sorry I don't want to show the final untill it is complete:

This has been somewhat easy to make and I have been in talks with a few companies that do over molding for the card slot connector and that's going to be my biggest hurdle I think. My intent is if I can get these produced cheap enough (say $50 or so to the end user) would there be an interest?

The small advantages to the design would be:

It sits flush with the system edge like a Hu does
No need for two converters this one will work on both systems
Your HuCard sits on top and flush with the adapter and not upside down or hung off the edge

Take note: This is not a scale model nor the final and traces are just for effect.

Thanks for any constructive criticism.

[ApolloBoy]

It looks fairly awkward to me, and honestly I much prefer having a region mod than a converter.

[majors]

No need for two converters this one will work on both systems

Both systems meaning US and JP? PCE users will still need to ground pin 29, right? Or you mean Duo and TG-16 systems? Do not leave out Express

[Ninja16608]

It looks fairly awkward to me, and honestly I much prefer having a region mod than a converter.

Like i said its an early concept and the final looks much nicer. This would be for people who do not want to mod their system.

[Ninja16608]

No need for two converters this one will work on both systems

Both systems meaning US and JP? PCE users will still need to ground pin 29, right? Or you mean Duo and TG-16 systems? Do not leave out Express

I have thought about it and I want to find away that no internal mod is need. This would be for people who don't want to mod their systems and yes I have included the express and have worked on making sure it fits. I have an express and a PCE at the moment to test how it fits.

[wolfman]

I have thought about it and I want to find away that no internal mod is need. This would be for people who don't want to mod their systems and yes I have included the express and have worked on making sure it fits. I have an express and a PCE at the moment to test how it fits.

Great concept! If it´s available for a fair price I´d give a try. Since I only own PCE systems this would be a nice thing me and all other members not wanting to mod their rare LT/Supergrafx.

How do you make your way around the necessary grounding of pin 29?

[Ninja16608]

I have thought about it and I want to find away that no internal mod is need. This would be for people who don't want to mod their systems and yes I have included the express and have worked on making sure it fits. I have an express and a PCE at the moment to test how it fits.

Great concept! If it´s available for a fair price I´d give a try. Since I only own PCE systems this would be a nice thing me and all other members not wanting to mod their rare LT/Supergrafx.

How do you make your way around the necessary grounding of pin 29?

I'm working with an electrical engineer to come up with a solution. I do hope we can find away around it with out having to open a system and "mod" it. Everything I have seen so far leads me to believe that this will go off without a hitch for US Turbos, its just a matter of flipping pins on the game to match the system. For the PCE we are doing further research, but as far as I can see it's pretty much the same as the TG16 would just require data channels to flipped and pin 18 on both JP and US games is a straight through ground and 15- 23 I believe of the top of my head were flip flopped.

[wolfman]

pretty much the same as the TG16 would just require data channels to flipped and pin 18 on both JP and US games is a straight through ground

Then why all that fuzz about lifting a pin from a chip for a region mod?

[Ninja16608]

pretty much the same as the TG16 would just require data channels to flipped and pin 18 on both JP and US games is a straight through ground

Then why all that fuzz about lifting a pin from a chip for a region mod?

If I'm understanding you right, your talkin about a hardware region mod on the console itself. As far as I know this is not needed with a converter card. I own one for the US system and it works fine with no mod to the system. I am reading up on the PCE but I don't think a mod would be needed, the hardware is pretty similar save the data channels.

[majors]

I am reading up on the PCE but I don't think a mod would be needed, the hardware is pretty similar save the data channels.

I'm no expert, but I'm pretty sure the PCE has a region lock along with the card pin swap(data channels) to prevent US games from running in JP. I guess NEC never thought we'd import so they did not implement it on the US family of obey. I'm sure you'll find the tech details out there.

At least Klax will work

[SephirothTNH]

I am reading up on the PCE but I don't think a mod would be needed, the hardware is pretty similar save the data channels.

I'm no expert, but I'm pretty sure the PCE has a region lock along with the card pin swap(data channels) to prevent US games from running in JP. I guess NEC never thought we'd import so they did not implement it on the US family of obey. I'm sure you'll find the tech details out there.

At least Klax will work

This is true. Japanese cards don't care what system they are running on as long as the data pins are right. US cards will not work unless pin 29 on the CPU is grounded and the data pins are right.

[Nazi NecroPhile]

I suppose it's technically possible to get around grounding internally, but it'd require the converter to intercept the region lockout code and patch the rom on the fly.  Possible, yes, but probably not worth the effort.

By the way, fellow member db-electronics is making converters.  Perhaps you could team up with him on making a more compact converter with 'real' huey socket.

[Ninja16608]

I suppose it's technically possible to get around grounding internally, but it'd require the converter to intercept the region lockout code and patch the rom on the fly.  Possible, yes, but probably not worth the effort.

By the way, fellow member db-electronics is making converters.  Perhaps you could team up with him on making a more compact converter with 'real' huey socket.

I did see his, and that would be a great idea as I'm a fan of the "real" huey socket. I'm sure he wont want to share how he got his to work unless his requires the internal pin 29 mod also.

[Ninja16608]

So after talking with Charles MacDonald it is not out of the realm of possibility but it would also seem to be more work than its worth. I have not givin up on this by any means, it just means I will go forward with a normal converter and slowly over time I will try to figure out whats needed to make it work.

This is where it might get tricky as he states they may have more than one method of the region check

From Charles' E-mail

I think most (not all) of the US games use the same standardized region code because it was provided to them by NEC. In theory you could use some programmable logic to check for that sequence of instructions being executed, and then at the right time turn off the HuCard output and drive a different opcode on the bus to defeat the protection. But that's a lot of work and a lot of hardware to do one thing.

The system runs fast enough that it isn't feasible to use a microcontroller to do this check. It's important to detect the exact sequence because the I/O port is used all the time for the multitap and controllers, so you only want to interfere with the data read from the HuCard at the "right" time. I think some US games use a different sequence too (the programmers wrote the region check differently, it functions the same but the exact sequence of opcodes are different) so you'd have to check for multiple types of sequences other than the primary one most games use.


The hunt continues...........

[Vecanti]

I've been thinking of something like this for a while:
http://zepsus.com/product/magnetic-switch-7a/

You would still have to do region mod inside, but then you would not have to mod the outside at all. So no cutting the case for a "switch" basically.

You could mount this under the logo for example on your PCE.  Then when you move a magnet above it you switch to Turbo mode, swipe again to move back to PCE.   

You could get pretty fancy too, where you had an led light hooked up inside, so you could see a glow coming out from the HuCard slot or something, red for PCE and another color for Turbo. 

So it's sort of a "No Mod" solution. At least from the outside.

[Ninja16608]

I've been thinking of something like this for a while:
http://zepsus.com/product/magnetic-switch-7a/

You would still have to do region mod inside, but then you would not have to mod the outside at all. So no cutting the case for a "switch" basically.

You could mount this under the logo for example on your PCE.  Then when you move a magnet above it you switch to Turbo mode, swipe again to move back to PCE.   

You could get pretty fancy too, where you had an led light hooked up inside, so you could see a glow coming out from the HuCard slot or something, red for PCE and another color for Turbo. 

So it's sort of a "No Mod" solution. At least from the outside.

I have thought about similar things like that, but the whole idea was to not have to unsolder pin 29 and ground it (there are a lot of people like me who do not want to mess with it, not that we can't, but for being original un modded hardware sake) and some lazy people too, I won't leave you guys out either lol. I have seen many awesome low profile mods where switches were cleverly hidden and the bread board was inside tucked away nice. I could just do the easy thing and go the way another member (or feebay seller trying to peddle his stuff here, I have not seen him since) just make a switchable converter and still require the internal mod.

Seeing as how I am trying to avoid all that I think I will go with a regular converter with a better safer design where the front of the TG and converter are flush to eliminate the dangers of cracking the converter etc. I will continue to search for the solution. If anyone is up for the challenge and has some/any experience with TG16/PCE please don't be afraid to get on board and help out. Any cost savings from help from the forums translate to a lower over all price, not to mention all forum members who are interested in one will get a nice discount anyhow cuz I love you guys :-) ....no really I do, I come here and get my daily laughs at some of the shit that flies around here.

[Ninja16608]

UPDATE: For those that are following this thread. I have made some progress on the converter, as of right now it will only convert JP to US until I can figure out a way to inject the region code. After talking with Charles MacDonald, he mentioned that most of the games use a standard method for the region code (Read the e-mail yourself I'm too lazy to type it lol)

(Hi Allen,

The region check works as follows: US games read the I/O port built into the HuC6280 chip (the CPU) and check the value of bit 6. If that bit is zero, the system is a TurboGrafx-16 and the game continues to run. If that bit is one, the system is a PC Engine and the game jumps into a region of unmapped memory and crashes. Japanese games don't do any region check so they don't care about the state of that bit.

The console modification is necessary because bit 6 of the I/O port corresponds to a physical pin on the CPU itself inside the console. On a TurboGrafx-16 that pin is normally tied to ground, and on a PC Engine it's tied to +5V. So a region mod involves desoldering that pin and connect it to a SPDT switch so that the I/O port pin can be connected to +5V or ground as needed.

There really isn't a way to defeat this protection easily, because the I/O port is integrated into the CPU. There's no way to substitute a different value on the data bus when the CPU is reading from the I/O port for example.

I think most (not all) of the US games use the same standardized region code because it was provided to them by NEC. In theory you could use some programmable logic to check for that sequence of instructions being executed, and then at the right time turn off the HuCard output and drive a different opcode on the bus to defeat the protection. But that's a lot of work and a lot of hardware to do one thing.

The system runs fast enough that it isn't feasible to use a microcontroller to do this check. It's important to detect the exact sequence because the I/O port is used all the time for the multitap and controllers, so you only want to interfere with the data read from the HuCard at the "right" time. I think some US games use a different sequence too (the programmers wrote the region check differently, it functions the same but the exact sequence of opcodes are different) so you'd have to check for multiple types of sequences other than the primary one most games use.

In the end, it's just easier to take a ROM, patch out the region check, and run it on a flash cart. I know that's hardly ideal, but it takes less effort.

So did you find a connector that fits the HuCard well? People like myself and others have been hunting for a compatible connector for years, it seems like the only alternative is to remove them from used/broken systems. Any idea where I could buy some?

Regards,

Charles)


If anyone has any info on the opcodes sequence they care to share it would speed up the whole process :-)

And yes I am having connectors made :-) just might take some time as I have to do the leg work in my free time.


I have some photos of my progress but they are large, converting them down to add to post.

[wolfman]

If anyone has any info on the opcodes sequence they care to share it would speed up the whole process :-)

Maybe in the homebrew games development thread?

[Ninja16608]

Good call, I'll make a post there :-)