nfg.forums

I've read up on other people trying to mod a SNES to suit this revision of the security chip here and here and wanted to see if I could get a definitive answer. I've successfully added the 50/60hz switch as this SNES had the separate PPU chips, it's just the lockout that's causing issues.

When I feed the security chip +5v from the voltage regulator, it runs fine, but it obviously won't even show up anything on the TV with imports When I feed it GND, it doesn't load up. From what I've read here, that means the machine's in a constant state of reset and is in line with the F413B revision of the security chip at U8.

So, from what others have found out, I have two options. The first is the "silver" mod, where I remove the whole F413B chip and solder a connection from pin 10 from where the F413B chip used to be to pin 4 on the chip U10 (source). The problem is if this doesn't work, re-adding the security chip with those little legs will be painful

Second option was from this site that simonbelmont2 mentioned in one of the threads linked to above. I don't understand French, but the gist of the setup for tackling the security IC via a DPDT switch is as follows:


    [not connected] -- 1 | 1 -- [not connected]
U18, pin 7 (lifted) -- 2 | 2 -- U8 (F413B), pin 4 (lifted)
  Cart slot, pin 56 -- 3 | 3 -- 5v from voltage regulator via a 2.2kOhm resistor


This appeals to me more as it doesn't involve the complete removal of the security chip, and I happened to have a DPDT switch already in there (I didn't have any SPDT switches handy ). The question is - should this work, or if anyone has tried this before?

Of course there's option 3 - gutting the security IC from another SNES cart and use this guide as a basis for wiring the two together. I don't have any spare SNES games I'm willing to gut, and would prefer either of the other two options.

If anyone can lend their wisdom, I'd appreciate it. I just wish the console had an earlier revision security IC so it wouldn't have to be extra complicated to do this

There are another two options which allow compatbility with any region SNES game (Including SA-1 and S-DD1 games) and do not require a switch.

Last year a clever nesdev forum member called ikari_01 created a SNES CIC clone using a PIC 12F629:-
http://nesdev.parodius.com/bbs/viewtopic.php?p=58670&highlight=#58670
http://nesdev.parodius.com/bbs/viewtopic.php?p=59920&highlight=#59920
http://nesdev.parodius.com/bbs/viewtopic.php?p=60116&highlight=#60116
This is a multi-region CIC clone so will allow any SNES game to run

There is also a 'SuperCIC' version which is similar to the above but uses a PIC 16F630 and allows for a switchless SNES that can swap between 50Hz and 60Hz modes using the consoles reset button:-
http://nesdev.parodius.com/bbs/viewtopic.php?p=61236&highlight=#61236
Installation guides here:-
http://wolfsoft.de/wordpress/?p=603
http://wolfsoft.de/wordpress/?p=686
http://www.mmmonkey.co.uk/console/nintendo/cic/cic.htm

I hope that helps

there's another switchless mod my friend and I made up which would work fine.
if you want to bring the she's round I'm keen to have a go at one of these:)

Sorry for the belated reply - thanks Link83 for the guides for the other options, but I was particularly keen on using a simple switch since I had them handy

I was actually reminded about this thread thanks to phreak97, as he sent me a text to offer his services since I don't live too far away from his end of town (thanks for the offer mate!).

For those interested, I went ahead and gave the switch theory (as garnered from the French website) a whirl. Floating pin 4 from U8 (F413B) and floating pin 7 of U18 will get the machine to play imports (i.e., the SNES behaves the same way as applying GND to pin 4 on earlier revisions of the CIC); however, when I try and boot the machine with the switch going the other way (pin 56 of the cart slot connected to pin 7 of U18 and +5v via a 2.2kOhm resistor to pin 4 of F413B), I get a black screen, indicating the machine is running at a reset state.

I couldn't be bothered popping open the SNES again to confirm that pin 7 of U18 really does go to pin 56 of the cart slot, but if you wanted to make it a working solution, it would be better to run a wire from the pad underneath pin 7 of U18 to the DPDT instead of a wire from pin 56 of the cart slot. This would make the DPDT switch look like:


             [not connected] -- 1 | 1 -- [not connected]
         U18, pin 7 (lifted) -- 2 | 2 -- U8 (F413B), pin 4 (lifted)
Pad underneath pin 7 of U18 -- 3 | 3 -- +5v from voltage regulator via a 2.2kOhm resistor


Though I am curious about phreak97's method - spill the beans on the theory if you want, if I still had the SNES I'd be happy for you to take a look at it. Mind, if I did that, you'd be able to see my sloppy soldering skills, so at least this way I get to save face

Glad to hear you had some success

The reason I suggested ikari_01's PIC CIC clone method is because if you disable the consoles CIC as you suggested you cannot play any game that uses the SA-1 or S-DD1 enhancement chips:-
http://en.wikipedia.org/wiki/List_of_Super_NES_enhancement_chips#SA-1
http://en.wikipedia.org/wiki/List_of_Super_NES_enhancement_chips#S-DD1
http://en.wikipedia.org/wiki/List_of_Super_NES_enhancement_chips#List_of_Super_NES_games_that_use_enhancement_chips

These two chips require the correct response from the consoles CIC and will not boot without it, so just disabling the CIC or switching it into 'key' mode will not work. The only two options with 100% compatability (Assuming you also fit a 50Hz/60Hz switch) are:-
- Install both region CIC's inside the console, or
- Program a PIC to be a CIC clone and install in the console

Good luck with whatever you decide to do

hehe my mod works with native Sa-1 games, yet to check import Sa-1s.

basically it involves chopping the reset line from the cic to the ppus and attaching it to the 50/60 pins instead, so depending on what region Cart goes in you'll get either 50hz or 60hz. the CIC still runs normally it's just had it's function changed. the sa1 chip still sees it working perfectly.

there's a little more to polishing it up but that's the basic idea:)

@Link83: Thanks for the links - I now realise where you were coming from (maximising compatibility), whereas I was just being practical with what I had available The lists you posted have revealed a couple of games I might chase down at some stage, but that's for when I can be bothered popping open my SNES again

@Phreak97: Great theory! Out of interest, does your mod mean you can't override the refresh rate? I like the ability to change the refresh on the fly. I like the theory though!

not at all, there's nothing stopping you from installing an override switch:)
Although it kind of defeats the purpose:P