New Game Gear Radica (must add cart slot...)

Includes but not limited to: SNES, Genesis, Sega CD, PlayStation 1, Nintendo 64, Dreamcast, Game Gear and I guess the Virtual Boy.

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segasonicfan
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New Game Gear Radica (must add cart slot...)

Post by segasonicfan »

Hey peeps,
I figure it would be good to start a new thread for this to consolidate information all in one place and let people know about a great new project. Recently a company named Coleco released something called the "PlayPal"- A Radica-like device that incorporated 20 built-in Game Gear and Master System games. Apparently these have not been selling well though and so the product has switches distributors. The Coleco ones were sold at Target in late '06 but now a company called Kobian is distributing a new model via Wal-Mart, CostCo, and Fry's Electronic's stores. According to the new web site and from my experience, Fry's is the only store in the US carrying the product. Here is the new official site:

http://www.playpalworld.com/portable.html

Being a Huge GG/SMS/Sega fan I think it would be great to add a cart slot on this Radica style. Upon opening up the new revision (one without the screen), I have found that it looks remarkably like the Radica cuts, so much in fact that I suspect they were produced by the same no-name Chinese company. Here are some pics I took:

http://i18.photobucket.com/albums/b134/ ... 0_1122.jpg

You can see the mask ROM is JUST like the Radica's, even has 44 pins with corresponding VCC and grounding points!

Here's a closeup of the mask ROM:
http://i18.photobucket.com/albums/b134/ ... 0_1115.jpg
http://i18.photobucket.com/albums/b134/ ... 0_1114.jpg

Of course I immediately took the liberty of removing it and uncovering the traces:

http://i18.photobucket.com/albums/b134/ ... 0_1119.jpg
http://i18.photobucket.com/albums/b134/ ... 0_1120.jpg

It was a pain to remove since it's just like the Radica ROM and terribly easy to rip off the traces. :/

So I've been working on a pinout of course but have not been having the greatest luck. It is not pin-for-pin with the Game Gear ROM like the Radica was with Genesis ROMs. Here's the GG ROM pinout I whipped up with the help a cart and the edge pinout from Victor Kemp's site here:

http://www.geocities.com/vjkemp/sega/connect.txt

This is the pinout I came up with:
Image

As you can see the pinout is certainly not 44 pins and there is no way to make it such. The mark ROM pinout has 31 data lines (the rest are VCC, GND, or NC) whereas the GG apparently only has 25 :/ What's interesting though is that the GG/SMS data banks end at D7 and A15. Using the Radica ROM pinout I could immediately see that the higher byte data banks D8-D14 were NC on the Playpal (if using the same pinout). So I'm starting to wonder if the pinout is almost if not exactly the same. Also, MAYBE the GGOAC is in fact a Genesis of some sort since we all know the Genny was capable of SMS support. GG just has a larger color palette so maybe they could have just incorporated that? I am not sure.

In any case, this is going to be a difficult mod and so I need all the help I can get ;) The sad news is this version (unlike the Radica) has everything integrated onto the main "glob" chip and NO stereo/S-video output. It looks to be all composite and mono :/

As for the other Playpal w/the screen...my local Fry's was out of them so I will be ordering one online. This SHOULD have RGB output since the LCD will require it however, there is a flashed ROM instead of a mask ROM so adding a cart slot may be extremely hard/impossible :(

Okay, that's enough for my terribly long post. Feel free to correct any of my information as I am terribly unfamiliar with code, ROM data, flashing, etc. My expertise is in the soldering/modding area only :P

-Segasonicfan

EDIT: sorry for the pic mistake sparkfist ;)
Last edited by segasonicfan on Fri Apr 27, 2007 3:07 am, edited 1 time in total.
Skyone
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Post by Skyone »

I'm doing a bit of work with it, haven't got much where but I'll be sure to make use out of this information. :)

Did you notice above the start button trace, it says "STAST"? Thus proving your "Chinese knockoff" claim. :P
segasonicfan
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Post by segasonicfan »

Did you notice above the start button trace, it says "STAST"? Thus proving your "Chinese knockoff" claim. Razz
Lol, yup yup :P

I forgot to mention the rest of my progress, i actually found some REALLY interesting new info. Basically I tried booting up the system after disconnecting one trace at a time in hopes to find some unnecessary ones or connections used for the higher data banks (since the ROM is undoubtedly far larger than the norm 512k GG game). Behold the odd thing I came up with:

http://i18.photobucket.com/albums/b134/ ... 0_1126.jpg

http://i18.photobucket.com/albums/b134/ ... 0_1123.jpg

After cutting traces 1,2, 43, and 44 it actually booted to a whole new menu with a different product name LOL. I forget which trace was the primary one for this effect, but it was one of those. I also found after cutting trace 34 that it still booted to the menu but not games, meaning that this is probably a trace for a higher data bank. and here's the really interesting news: according to the Radica pinout, all those traces are higher data banks than a normal GG game has! Here's what they are on the Radica:

1: NC (maybe helps choose the menu change on the GG)
2: A18
44: A20
43: A19
34: A16

This is great news because the GG is limited up to A15 and D7 as mentioned before. So it looks like the pinout might be almost identical, minus the change in pin 12 to ground and pin 1. Pin 33 is also a jumper which I haven't quite figured out the use of yet.

Unfortunately I don't even have a working GG or other ROMs to test with right now, so my work on this will be halted for a couple weeks. My main pinout concern right now is the wiring of the WR (write signal) and MREQ (memory request lines). If I knew where to wire these on the GGOAC I would have a pretty fair chance of booting an external ROM :) Time will tell though and I'm happy enough with the progress so far (it has been only 3 days heh).

Hopefully you'll come up with some more good stuff skyone :)

-Segasonicfan
Last edited by segasonicfan on Fri Apr 27, 2007 3:13 am, edited 1 time in total.
dman762000
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Post by dman762000 »

hmmmmm that thing has nice little solder pads under the rom, should be easy to cart slot it
Skyone
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Post by Skyone »

Ya, I just took the mask ROM off, ripped about 30 traces :P. Unfortunately, this was my last playpal. So I need to either but another one or solder straight to the processor's traces. >_<

In this process, I gathered a rough pinout to the mask rom which is identical to your findings. This is good in the sense that we're on the same page. :P

I'll keep you guys updated.
segasonicfan
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Post by segasonicfan »

yeah, those solder pads don't help much at all :( Next time you're desoldering I recommend using desoldering braid and putting your iron at ~850 degrees. It soaks up a great amount and if you use an x-acto knife after that you can really minimize the damage. using this method I only ripped 3 or 4 traces :)

-Segasonicfan
Skyone
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Post by Skyone »

segasonicfan wrote:yeah, those solder pads don't help much at all :( Next time you're desoldering I recommend using desoldering braid and putting your iron at ~850 degrees. It soaks up a great amount and if you use an x-acto knife after that you can really minimize the damage. using this method I only ripped 3 or 4 traces :)

-Segasonicfan
Sounds better than what I did... I just x-acto knifed it all off - oh well! :P

I tried wiring it back on (took like 30 minutes) but it was a waste, for it didn't work :cry:. I'll have to pick up another one when I get to Fry's on Saturday. Keep me updated on anything you do!

Oh, and before the crap broke all over the place, I disconnected pin 44, and connected pins 1, 2, and 43 to ground. this made the alternate menu come up... but it was off-centered on the video - I can't tell if yours did this too. It also would NOT load any games after I selected them, probably due to a shift in memory...

As you assumed, pins 1, 2, 43 and 44 are all high-address lines that act as a bank switcher.

In conclusion, by hooking all four (1, 2, 43, 44) to ground, you bank-switch to the alternate menu-select, just as you would switch between the 6 games on the Radica. I'm sure you can unlock even more banks by hooking the pins up to either ground or 3.3v as devster did with the Radica. That should solve that idea.

My guess on the pinout after this:

Code: Select all

1:  A21 - bank
2:  A18 - bank
3:  A17
4:  A7
5:  A6
6:  A5
7:  A4
8:  A3
9:  A2
10: A1
11: A0
12: CE (signal low, ground)
13: GND
14: OE (signal low?)
15: D0
16: D8
17: D1
18: D9
19: D2
20: D10
21: D3
22: D11
23: VCC +3.3v
24: D4
25: D12
26: D5
27: D13
28: D6
29: D14
30: D7
31: D15
32: GND
33: BYTE (signal low? not connected)
34: A16
35: A15
36: A14
37: A13
38: A12
39: A11
40: A10
41: A9
42: A8
43: A19 - bank
44: A20 - bank
Any other ideas?
Life of Brian
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Post by Life of Brian »

You guys amaze me. How does one even start learning how to understand what the heck you are talking about? I wish you the best of luck, even though I haven't a clue what is going on.
dragonhead wrote:sweet. ive spent a third of my life on benheck!
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segasonicfan
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Post by segasonicfan »

Skyone,

yeah, that's basically what I was saying about the higher banks. If you leave the disconnected pins floating you will get a menu synced up correctly. Looks like the pinout is the same as the Radica though according to both our finds. The only difference being pin12 which may be that signal but is always connected to ground on the unit. Like I said though, I'm really not knowledgeble when it comes to data banks and whatnot. However, it should still boot Columns with those pins disconnected. I tried it because I figured it would run on a lower databank and it does. Of course it actually boots the Sonic Spinball game but hey, that's good enough for me :)

I ordered the portable version which should be here Monday. The others I was working on are already broke, lol. Looks like this guy breaks extremely easily unlike the Radica :/ At least my ROMs work though. You should also check out the work being done on this at the SMS forums:
http://www.smspower.org/forums/viewtopi ... 93ddaac47f

Apparently they are running into a lot of problems :( That's the portable version that uses a flashed ROM and not a masked one like the radica so MAYBE we'll have better luck with the new revision. It definitely has multiple changes to the circuitry and I believe it is an altogether completely different CPU chip.

joedog- thanks for wishing us luck :) I just started learning about this actually by looking through GG documentation and the mapping out of the GGs circuits :)

-Segasonicfan
Skyone
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Post by Skyone »

Yep, I was actually googling some stuff to see if anyone had done any work on this, and you username popped up on the SMS Power forums.

I know this seems like a stretch, but since my board is dead, I'm going to see if I can get the epoxy off of the processor by freezing/heating rapidly (gotta go get some dry ice!). Even if I could get it off, I doubt the electronics inside would still be alive, but hey, I just wanna check out what it looks like and who produces it. :P

The other revision you linked me to looks like it has the same processor as this one, but the memory looks like something straight out of an iPod nano, so flash memory. He obviously dumped the ROM, so I suppose they might know how to interface with it.

For me, on the other hand, I'd rather stick to the simpler one for now. It's very interesting to see done, so I'll keep my eye on it.

-Skyler
segasonicfan
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Post by segasonicfan »

Lol I just bought another one of the simpler ones at Fry's today...I couldn't resist since I'm buying one for Hotdog cart anyway :P

I'm pretty sure the other one is a *slightly* different processor since it has so many extra components not found in this one (and they are definitely not all used for the speakers and LCD). But yeah, that one is going to be next to impossible to add a cart slot too :(

BTW, pin 33 is actually connected to ground via a jumper. Lift up the solder and you'll see the tiny jumper :P to the right is a jumper to +5v. I just managed to fix my GG last night (it broke a long time ago) and so now I can test my games on that again and maybe use it as a reference for the pin voltages or something. Though I think you (and I) are correct (lol), it looks to be the same pinout as the Radica. This would make sense too since they wouldn't have to make new mask ROMs.

Does anyone have a picture of the Radica mask ROM? I'd like to see just how similar they are...

-Segasonicfan
Skyone
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Post by Skyone »

segasonicfan wrote:Does anyone have a picture of the Radica mask ROM? I'd like to see just how similar they are...
Image
Image

There you are...

I've also noticed some minor PCB differences in our mask ROMs, but it's probably nothing. I too picked another one up at Fry's today (damn, maybe we were there at the same time, which one did you go to? :P) and will open it tomorrow for more experimentation.
segasonicfan
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Post by segasonicfan »

ugg...I just wired up a game gear cart (wonderboy II) perfectly to that pinout and I still just get a blank screen :/ I imagine its something with the enable pins but I got to say I'm really at a loss :( Hopefully you will have better luck..

-Segasonicfan
Skyone
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Post by Skyone »

I just removed my ROM from the board, pretty clean rip. I'm wiring up the ROM to a prototype board and the PCB to the prototype as well to mess around with everything.

Wish me luck!

-Sky
Skyone
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Post by Skyone »

Bumpity bump:

<img src="http://skytroniks.com/two/upload/IMG_1529.JPG" width=432 height=288 border=0>
<img src="http://skytroniks.com/two/upload/IMG_1532.JPG" width=432 height=322 border=0>
Click for a larger view.

There's the mask ROM all wired up to be tested. I've also wired up the PlayPal's ROM connection pads to the board next to the mask ROM... I should be able to wire it all up and do some massive testing soon! :)
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