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PostPosted: Mon Aug 17, 2015 5:20 am 
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Hi all

Was about to do my first supercic mod when i opened up my super famicom and found leg 1 and leg 10 have been connected see pic. I assume that this is not factory ?

Is this a previous mod?

Do I just remove this then do the install ?

Thank all "newbie learning here"


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PostPosted: Mon Aug 17, 2015 11:33 am 
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At first I wanted to say that it looks like an official post-factory mod, because of the zero Ohm resistor. No one uses those, so it looks legit, but these two pins are p00 and reset. if I am not mistaken, the bridge could potentially reset the console unexpectedly but I assume it works or you wouldn't be attempting a mod.

Its absolutely bizarre. Whatever it is, it is not present in the schem found here;
viewtopic.php?f=12&t=10470


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PostPosted: Mon Aug 17, 2015 12:05 pm 
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Definitely a post-factory/unofficial/homebrew mod (and a lousy one at that).

Dark-Link wrote:
Do I just remove this then do the install ?

Yes. :)

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PostPosted: Mon Aug 17, 2015 5:26 pm 
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Jazzmarazz wrote:
At first I wanted to say that it looks like an official post-factory mod, because of the zero Ohm resistor.

... Can someone briefly explain to me why a zero-ohm resistor EXISTS? That just a piece of wire, isn't it?


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PostPosted: Mon Aug 17, 2015 5:35 pm 
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It's reasonably heat proof (unlike ordinary wire insulation), and it's electrically insulated, so unlike a plain jumper the center can't accidentally short to anything.

It also says "No, really, these are supposed to be shorted", whereas a random anonymous wire can be harder to tell.


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PostPosted: Mon Aug 17, 2015 5:39 pm 
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Khaz wrote:
Jazzmarazz wrote:
At first I wanted to say that it looks like an official post-factory mod, because of the zero Ohm resistor.

... Can someone briefly explain to me why a zero-ohm resistor EXISTS? That just a piece of wire, isn't it?


They exist as jumpers that can be easily placed by pic and place machines.


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PostPosted: Mon Aug 17, 2015 6:28 pm 
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Thanks for the answers, glad to finally understand that!


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PostPosted: Mon Aug 17, 2015 8:44 pm 
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Anyone have an explanation of what the guy was trying to do here?

The CIC can be bypassed by lifting pin 4, which also allows cart-swapping, although that breaks SA-1/S-DD1 games that refuse to play with non-functioning CICs. I did this mod with a sewing needle and a whole lot of patience.

Never heard of a CIC bypass by linking pins 1 and 10.


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PostPosted: Tue Aug 18, 2015 10:55 am 
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byuu wrote:
Anyone have an explanation of what the guy was trying to do here?

It's a proof-of-concept of »I don't know what I'm doing, but I'll try anyway.« :lol:

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PostPosted: Tue Aug 18, 2015 4:06 pm 
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Generating the /Reset signal is the main purpose of the cic chip (apart from the region locking stuff). My theory would be: If the cic does output only weak low levels (and stronger high levels), then shorting that two pins would cause /Reset to go low only if both pins are switched to low levels.
The mod will almost certainly cause a region-error, so the cic will try to pull /Reset low, but the other pin might prevent that, so the game would keep running despite of the error (whilst on power-up or reset-button, both pins might be low, so the game would get reset properly).

If that's really working then it would be a quite brilliant solution, because shorting two pins is much easier than lifting a pin; especially as the pins are located right at the chip edges.

Can anybody confirm if the mod is really working? Checklist would be:
1) console should still boot on power-up
2) console should still reboot when pressing the reset button
3) if the mod is of any use, then the console should accept games from other regions (or games without cic)


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PostPosted: Tue Aug 18, 2015 7:17 pm 
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> If that's really working then it would be a quite brilliant solution, because shorting two pins is much easier than lifting a pin; especially as the pins are located right at the chip edges.

My thought exactly! And it would also be trivially reversible. Just need a solder sucker.

Or even better, put a physical SPST across these two pins instead, if you can find a good one with sturdy yet flexible legs for it.

> Checklist would be:

A fourth test would be verifying that SA-1/S-DD1 games do *not* work with this mod installed, in case you don't have any other region or CIC-free carts.


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PostPosted: Wed Aug 19, 2015 4:22 am 
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Hi all

Firstly thanks you for the responses "learning a lot here" appreciated

yes well the machine does work I was playing a pal AUS game on it the other day.

I have had it for a while but it's been packed away and I haven't really done much with it. "Been using my pal snes"

I will test the options suggested asap and let you know what I find out

Thanks again all


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PostPosted: Wed Aug 19, 2015 4:01 pm 
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Just to be sure: The console is a japanese NTSC super famicom, and it plays australian PAL games? Or in other words, the mod allows to play both PAL and NTSC games, right?

Would be interesting if it's fully working without issues (ie. the Reset button should be still working, etc. see above).

If somebody has a fresh unmodded console, it would be interesting if shorting the two pins (with a wire) works there, too. Just to confirm that it's working, and that the photo is really showing the whole mod (theoretically there might be further mods not visible on the photo).


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PostPosted: Wed Sep 02, 2015 9:19 pm 
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Since I just opened my SNES to help poot36, I figured I'd touch a scope probe to pin 10, and then short it to pin 1 (using tweezers), and then hit reset.

It sure seems to work... Shorting the two pins makes the CIC get in a fight with itself, and (strangely) its pullups seem to be stronger than its pulldowns. I saw about 3.5V on pin 10 when the pins were shorted. Hitting reset drops the combined signal to 0V, and it rises back to normal afterwards.


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