Region switch on original white PC Engine

[nopepper]

Hoping to get some ideas as to what the recommended approach is to region mod an og white PC Engine. I'd like to just reuse the RF switch hole so as not to make any modifications to the casing, similar to what is explained in this guide: www.mmmonkey.co.uk/multi-region-pc-engine-turbo-grafx-16/

Looks like the obey chip is no longer being sold, so what are the alternatives? Do I just breadboard and take the old school approach, or are there other premade boards readily available in the USA? 

Also, read somewhere that lifting pin 29 on the HuC6280 is no longer recommended, since you can bridge with pin 30 (IIRC). Does this apply to the white PCE as well?

[keithcourage]

This is what I like to use. Chip is CBT3383. Has better compatibility with Everdrives compared to the older 4551 chip mod. The capacitor shown in the pic is not needed

[nopepper]

Is that PCB your own design and is it readily available somewhere to download so I can have the PCB manufactured (or purchase from you)? Also, do you know if the obey boards or similar are available somewhere? I kinda like the idea of not having the mess of wires that this one will require, but I would be fine if my only option.

In any case, appreciate the suggestion.

[nicole]

Nov 12, 2020 1:15:13 GMT nopepper said:

Also, read somewhere that lifting pin 29 on the HuC6280 is no longer recommended, since you can bridge with pin 30 (IIRC). Does this apply to the white PCE as well?

I think this only applies to Duo consoles; pin 30 is the CD-ROM detect pin, so you'd only be able to play US games with a CD-ROM attached if you bridge them on the white PCE as far as I know.

[dshadoff]

Yeah, connecting pins 29 and 30 wouldn't change anything, except it might trick the system into thinking there's a CD device.  Or short out the machine...


...But you shouldn't need to lift a pin of the Hu6280 either.

Look at the TurboGrafx service manual here:
gamesx.com/wiki/lib/exe/fetch.php?media=schematics:turbografx-16_unit_service_manual_-_smtg16.pdf

You will see the R138, a 0 ohm resistor, brings the pin to ground state on the TG-16.
A similar technique is likely in place for all Japanese consoles, but raising the pin to 5V instead of ground.

The resistor may be a pull-up resistor with a value between 10K and 100K, or it may be 0 ohm as here... I doubt that it would be a direct line to 5V.

Assuming that an analogous resistor is there, remove it (it should be surface-mount).  You can solder to the chip-side pad, instead of directly to the pin.

[nopepper]

Ah, my aging memory mangled this up and confused with what is explained in this video at ~3:00, where he states you just need to solder a wire from pin 29 to ground and you should be good to go: www.youtube.com/watch?v=bY-cxzWojoI. That is for a Coregrafx II console, so not sure how that differs with the PCE.

Once I have sourced all parts for the region mod, I'll crack it open again (I just replaced all caps and fuse, since I was getting no power and video), and see if I can follow your recommendation regarding the resistor.

Thank you and Nicole for the info, I really appreciate it.

[dshadoff]

On each machine, the resistor will be a different part ID (that is to say, it won't be R138)... but it shouldn't be too hard to find, I hope.

[ivanbeavkov]

Here is a another region mod. It is optimized for DUOs but can be installed in any PC Engine/Turbo console.

www.game-tech.us/product/turbo-duo-pc-engine-region-mod-kit/

Unfortunately it is currently out of stock but he restocks regularly.

[keithcourage]

Nov 12, 2020 23:06:57 GMT nopepper said:

Is that PCB your own design and is it readily available somewhere to download so I can have the PCB manufactured (or purchase from you)? Also, do you know if the obey boards or similar are available somewhere? I kinda like the idea of not having the mess of wires that this one will require, but I would be fine if my only option.

In any case, appreciate the suggestion.

PCB is just a Sop 24 pin adapter board www.ebay.com/itm/2Pcs-SMD-SOP24-SSOP24-TSSOP24-to-DIP24-Adapter-PCB-IC-Converter-Plate/352307045159?hash=item520722e327:g:g6MAAOSwhktaq-uA

I have CBT3383 chips and Sop24 boards on hand. If you want one, $14 shipped in the US. I don't have any smaller SPDT switches at the moment. 

[nopepper]

Nov 13, 2020 19:50:01 GMT keithcourage said:

Nov 12, 2020 23:06:57 GMT nopepper said:

Is that PCB your own design and is it readily available somewhere to download so I can have the PCB manufactured (or purchase from you)? Also, do you know if the obey boards or similar are available somewhere? I kinda like the idea of not having the mess of wires that this one will require, but I would be fine if my only option.

In any case, appreciate the suggestion.

PCB is just a Sop 24 pin adapter board www.ebay.com/itm/2Pcs-SMD-SOP24-SSOP24-TSSOP24-to-DIP24-Adapter-PCB-IC-Converter-Plate/352307045159?hash=item520722e327:g:g6MAAOSwhktaq-uA

I have CBT3383 chips and Sop24 boards on hand. If you want one, $14 shipped in the US. I don't have any smaller SPDT switches at the moment. 

Awesome, thanks for the info.



I think I'll source the parts and see if I can get this working, as I also have a Duo I'd like to region mod, so will need more than one.

[nopepper]

Nov 13, 2020 14:16:39 GMT ivanbeavkov said:

Here is a another region mod. It is optimized for DUOs but can be installed in any PC Engine/Turbo console.

www.game-tech.us/product/turbo-duo-pc-engine-region-mod-kit/

Unfortunately it is currently out of stock but he restocks regularly.

I've been checking game-tech for the past couple of months and it always seems to be out of stock, so I think I'll try Keith's suggestion and build it myself. 

[keithcourage]

Here is another diagram for the CBT3383 chip that might help if that's what you decide to use.


alternatively there is also the option of using a 8pdt switch like this www.amazon.com/uxcell-Self-Locking-Button-Switch-Position/dp/B07P7CS68M

But then you would have to glue it to the upper portion of the case to hold it in there+it wouldn't fit in the slot near the RF port that you are trying to use. Here is an example of a finished one. postimg.cc/bShFFw3d

[nopepper]

Thanks again for all the info Keith, I got this to work without much fuss. Most challenging things were a) removing the RF modulator and b) making the mess of wires fit in such a tight space.



In regards to PIN 29, I could not trace to any resistor and could not find schematics online, so I just lifted and grounded the pin. Prior to lifting, I tried just grounding, and USA games would start playing, but freeze in the same spot, although different in every game I tried. For example, in Bonks Revenge, it would lock up after intro sequence, when the level demo started playing. In Dungeon Explorer, it would be after opening music played for a couple of seconds, just before text starts scrolling.



This was a "junk" PCE a japanese colleague of mine had for years, so it's been gratifying bringing it back to life and allowing it to play games from all regions. I also like the fact that I did not have to modify the case at all, making this reversible if need be.

[czroe]

So no one is currently selling one of the nice region mods on a custom PCB other than Doujindance on eBay? Weird. Been looking for the past week and that's what led me back here.

Anyway, I have a couple white PCEs and I plan to remove some known-good chips from one to repair a TurboGrafx-16. If I end up removing the CPU I'll trace pin 29 but I suspect it doesn't involve a resistor since there's a good chance they hadn't decided to use pin 29 for signaling region when that PCB was laid out.