REGION MOD FOR TG-16/DUO/PC-ENGINE

[Michael Helgeson]

Bump. Go back to the top of page 1,more info added including place to buy switch.

[SignOfZeta]

I think you need to add to your sig. Its not big enough.

[Michael Helgeson]

Yea me too,not sure what else to add though,then again,it probably looks really big to anyone who can only use 800x600 or 1024x768....

[termis]

You can also order an 8PDT push-button switch from here.

http://www.surplussales.com/Switches/SWPushB-1.html

Part#: (SWP) 120SA.1X11

[Michael Helgeson]

Good switch,but they only let you do a minimum of a $10 order,before shipping. Not sure how much Im willing to spend,prob would be fine if I needed 2 of them,or maybe a group order.

[termis]

Just wondering out loud for those who may want to mod a SuperGrafx system.   I don't know if anyone has even thought about this very minor issue (but annoying to some - like me!), but if anywhere, I'm sure this is the place to find such people.

According to multimods.com, 2 games will not work correctly with a modded SuperGrafx for some reason. 

*  Certain games have known issues with region mods on the SuperGrafx system:

       1. Aldynes - plays fine, but if you allow the system to go into Attract Mode (demo at beginning), it will freeze.
       2. Space Harrier - game apparently loads and then quickly freezes.

The ONLY reason that I can think of Aldynes freezing up is because of the pin 29 ground mod (which would be required only to play US games, not JP games).  This is because once the switch is set to JP mode, the whole entire logic of the system is EXACTLY the same as an unmodded system, MINUS the aforementioned pin 29 of HuC6280. 

And I'm not sure which version of Space Harrier he was mentioning, but if it's the JP version that freezes, then it's got to be the same issue as above, unless Space Harrier for some reason has an inherent compatibility issues with the SuperGrafx.   If both or just the US version of the Space Harrier has this problem, I can only guess it'd be some kind of internal compatibility issue with the SGX and would give up on this problem.

Now, if not grounding pin 29 cures the problems the above two games, then one can either:
1. Use an SPDT switch just to either ground or not to ground pin 29 of HuC6280.
2. Add a DPDT switch instead of the SPDT switch to the ic mod, and have one side control the ics like it normally would, and the other side control the ground of pin 29.
3. Find a 9PDT(!) switch and do the same as #2.  (Can you even buy a 9PDT switch? You might have to custom build this one, which in case, might as well go with option 2!)

Okay, so maybe this is a whole lotta rambling for just 2 games, but if the above works, this would be the ONLY true way to get a system that plays 100% of HuCard games.  That's gotta be worth something, no?   

Actually, I'll go post this in gamesx forums too, to see if anyone knows/has thought about this issue...

[GUTS]

Yeah this is good to know, but I have no problem paying for the mod either.  I could do it myself, but for the $50 it costs I'd rather let somebody do a professional job.  D-Lite did a SWEET job on my white Duo, so it was worth every penny.

The AV stuff though I was going to try myself, I'd love to get my Duo hooked up through component.

[Michael Helgeson]

I wouldn't mind doing it,but I have ZERO experience with the insides of a SuperGrafx. I only know one person personally and its doubtful he will ever pop his open cause its in near mint condition. Without prior knowledge of how the insides look I wouldn't be sure just how much empty space I had for said switch so possibly both would have to be ordered in advance just incase.

[SignOfZeta]

According to multimods.com, 2 games will not work correctly with a modded SuperGrafx for some reason. 

Yeah, that is puzzling, and I have no idea why this would be the case if the mod itself was perfectly performed.

At the time though, what's with that one RPG demo disk with TM2, and Dragon Slayer demos on it? I sold mine years ago but from what I remember the TM2 portion of the demo does not work on US systems...and this is a CD I'm talking about.

[Black Tiger]

According to multimods.com, 2 games will not work correctly with a modded SuperGrafx for some reason. 

Yeah, that is puzzling, and I have no idea why this would be the case if the mod itself was perfectly performed.

At the time though, what's with that one RPG demo disk with TM2, and Dragon Slayer demos on it? I sold mine years ago but from what I remember the TM2 portion of the demo does not work on US systems...and this is a CD I'm talking about.

Although I haven't tried it in years, I think that that might've happened to me as well, although I do remember playing the TMII demo at some point.

It's probably just a weird bug like Alterd Beast CD.

[termis]

Things that make you go hmmm....

Anyway, I do have a SuperGrafx system, but I haven't modded, nor even opened it yet.  But looking at it from the outside, it seems to have plenty of room to squeeze to in what you need.  It certainly should have more space than a CoreGrafx, and I managed to squeeze in an 8PDT switch in there (though barely!).

The problem is that I don't have either Aldynes nor Space Harrier to test out my theory.  For Aldynes, it's pretty much a clear yes-no outcome.  Since it's a jp only supergrafx game, there's isn't many different combinations to test.  It'll work, or it won't, on a supergrafx with pin 29 not grounded.

Space Harrier, however, has a lot of different possible combinations.  If anyone can help me so I can narrow down the possible reasons for the problem... Please let me know if you played:
1. US or JP Space Harrier on any modded Japanese PC-Engine systems.
2. JP Space Harrier on a US TG-16/T-Duo, either modded or with a converter.
3. JP Space Harrier on a SuperGrafx, modded or not (and the system switch settings on both normal PCE mode and SuperGrafx mode).
4. US Space Harrier on modded SuperGrafx (once again, on both PCE/SGX settings)
And if so, did it play okay?  Did you get any of the freezing that was mentioned above?

[Black Tiger]

Things that make you go hmmm....

Anyway, I do have a SuperGrafx system, but I haven't modded, nor even opened it yet.  But looking at it from the outside, it seems to have plenty of room to squeeze to in what you need.  It certainly should have more space than a CoreGrafx, and I managed to squeeze in an 8PDT switch in there (though barely!).

The problem is that I don't have either Aldynes nor Space Harrier to test out my theory.  For Aldynes, it's pretty much a clear yes-no outcome.  Since it's a jp only supergrafx game, there's isn't many different combinations to test.  It'll work, or it won't, on a supergrafx with pin 29 not grounded.

Space Harrier, however, has a lot of different possible combinations.  If anyone can help me so I can narrow down the possible reasons for the problem... Please let me know if you played:
1. US or JP Space Harrier on any modded Japanese PC-Engine systems.
2. JP Space Harrier on a US TG-16/T-Duo, either modded or with a converter.
3. JP Space Harrier on a SuperGrafx, modded or not (and the system switch settings on both normal PCE mode and SuperGrafx mode).
4. US Space Harrier on modded SuperGrafx (once again, on both PCE/SGX settings)
And if so, did it play okay?  Did you get any of the freezing that was mentioned above?

It turns out that I don't have either version of Space Harrier.

But if you think it might help at all, I can try each rom through my flash card on my modded Duo RX and one of my unmodded Turbo systems. If you think it's make a difference, I could see if the flash card will fit into my kisado to play the PCE version on my Turbo Duo.

[termis]

It turns out that I don't have either version of Space Harrier.

But if you think it might help at all, I can try each rom through my flash card on my modded Duo RX and one of my unmodded Turbo systems. If you think it's make a difference, I could see if the flash card will fit into my kisado to play the PCE version on my Turbo Duo.

Hey, that'd be sweet, if it's not too much trouble for ya!

For those of you that know what I'm saying, here it is:
*original image removed per request and replaced with this one*


Essentially, this is the same as the two-ic mod, with a DPDT switch thrown in the end, to control the ground of pin 29.   However, since I don't know which switch position is JP and which is US in the ic mod, it's possible that the position of the two arrows (ground & PCB of pin 29) may need to be swapped.  It's either one way or the other.

It really isn't that much change to the ic mod - a different switch and 3 extra wires.  If done correctly, the worst possible outcome is that it'll just add a few wires to the mod.   At best, it'll solve the issues with the two games, making SuperGrafx 100% compatible with everything! 

If this mod doesn't solve the SuperGrafx issue, I can't imagine what else it'd be...  I'd guess it'd be some compatibility issue between the PC Engine and the SuperGrafx that wasn't previously known...

[Moosmann]

@ Michael Helgeson
@ thumpin_termis
Those photos and graphics are subject to my copyright. A use without previous arrangement is not allowed.

To the modification: Pin 9 from the MC14551B are only “Enable” Pins. I think, it is >maybe< possible to only connect lifted Pin 29 (from the Hudson-Chip) to the enable Pin 9 from the ICs.
If you have a US System you can solder like this schematic, for the Japanese systems you exchance the wire diagram on one side. I mean, instead  A --> H, you solder H -->A sequence in reverse >only< on the connector >or<  pcb side.

Here is the datasheet:
http://pdf1.alldatasheet.com/datasheet-pdf/view/11991/ONSEMI/MC14551B.html

Bye Markus
Owner from http://mbrandel.vizionaires.net/

[guyjin]

Those photos and graphics are subject to my copyright.

prove it.