Connect SNES pads to a Supergun

Started by Cisco, February 18, 2006, 03:46:51 AM

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Cisco

I want to do a super gun that supports snes pads. I don't want to modify the sned pads, but add internally support to the supergun to decode de snes pads signal and translate them to jamma ones... it is possible in any way?
Can I recycle snes console components to do this or can I program a cheap chip to do this function?  :rolleyes:  

atom

You are years of learning about electrical engineering and programming away. Thought Id tell you up straight. There is a wiring alternative of modifying the pad if you are interested.
forgive my broked english, for I am an AMERICAN

NFG

There is a chip that will decode the SNES pads without special programming.  I don't recall the part number, but it's basically the reverse of the SNES pad chip (A 744011 IIRC?).

Basically it's a serial to parallel, reversing the pad's parallel to serial encoding.

atom

Oh nice, I didnt even consider something like that would exist. But he wouldnt want serial would he? He would need all the buttons to have their own line.
forgive my broked english, for I am an AMERICAN

NFG

You might want to re-think the concept, atom.  If there's a parallel->serial in the pad, and another chip converts serial->parallel, he doesn't have serial anymore does he?

Guest_Cisco

Mmmm... then can I do what I asked? I don't think I have understood excatly what you say... what I exactly want is to use SNES PADS with a supergun without any mod to the pads, so I need a chip that receives snes pad input (via its 5 of 7 used pins) and translate it to each button wire (four directions, 6 action buttons, select and start) to use as input on jamma.

Can you explain Lawrence in a more detailed way what dit you excatly want to mean? I didn't understand it fully because of the language and my poor knowledge about electronics, as atom said... sorry  :unsure:  

atom

QuoteYou might want to re-think the concept, atom.  If there's a parallel->serial in the pad, and another chip converts serial->parallel, he doesn't have serial anymore does he?
:D Long day.
forgive my broked english, for I am an AMERICAN

NFG

Cisco: There are two options to what you're asking for.  

1. You want us to do it for you, create the circuit and provide you with a working diagram, or

2. You want us to point you in the right direction and you'll figure it out yourself.

From your response I'd say you're not ready for 2, and this site and forum do not, sadly, cater to the former.  GameSX is not a place for finished solutions, it's a place for ideas and reference material.

Here's answer 2 anyway:

The SNES controller converts a set of parallel inputs (the buttons) to a serial signal.  This is all explained here.

There are chips that do the reverse.  You'll still need a clock, a PCB and some wires and solder, of course.

Don't take my word for it, but in the 10 seconds I devoted to looking it up I found this 74SL673 chip which might work for the job.

Guest_Cisco

Well I've been looking for info since your last answer. Is not that I want you to do it for me... only I thought someone could have done it before (like directpad connections and drivers are) so I can use his schematics. As I searched and searched but haven't found any schematics on the net, only ones for mega drive 3 button pads to jamma connection, but not for mega drive 6 buttons or snes pads, that's why I asked.

I'm interested in doing this conversion but I don't know how to do it. If there are no schematics, obviously I will not discover them because I don't have the necessary knowledge. So thats why I asked. It's not that I want somebody to work for me.

Thank you anyway for your answers, I've been looking at the info of the 74SL673 chip but I really don't understand if it alone is able to give me the serial to parallel conversion to connect directly to jamma harness.

NFG

What you're trying to do is relatively difficult.  I've never done it, though I've often thought of it.  It's just not something I coinsider interesting enough to bother.  Obviously the lack of documentation online would indicate I'm not alone in this.  

If I had to do the project right now, I'd start by researching the proper chip (not sure if the one I linked is the right one, I think it is) and then, by reading the datasheet, working out how it worked, then whipping up a circuit in a breadboard and trying it out.

If that's beyond you, you'll either have to pay someone to do it for you or wait until someone does it and publishes their instructions.

If it was easy it wouldn't be fun.  =)

kendrick

In the interest of uncovering the information, I would suggest checking out information on the home CPS boards. These guys accepted input from regular Super Famicom controllers and translated it into signals that the arcade board could handle. It might not be a complete solution, but it's a step in the right direction.

-KKC, ready for a nap.

NFG

kendrick: the boards you refer to used a single CAPCOM-labelled chip, probably a microcontroller, to do the job.  Nothing to be gleaned there.

Guest

It's pretty simple. I implemented a decoder for 4 SNES pads in a CPLD for a Supergun I never got around to build last year, not sure if I still have the design though :( The hardest part was building the actual clock circuit :) I don't have the thing in front of me but I think I just used a programmable 5 bit counter with bit 5 strobing the controller and shift regs, (the counter was set to count from 0-16.) Other than that you need the 16 bit shift registers for each pad (or you can cascade a few together) and you're set.

D-Lite

For all the effort to convert the signal (which I would love to find and implement too) you could easily buy a second set of SNES pads and internally mod them for the job.  Not trying to rain on any parades, just stating that with SNES pads being cheap you should consider that.  

kyuusaku

#14
I'm guest by the way ;)

Generic pads may be cheap and a dime a dozen but the original North American $15.99-in-1993 SNES pads are insanely hard to find new or as new due to the market being flooded with knockoffs, sadly the original pads are all I can stand (they even beat brand new SFC pads!) so modifying them was not an option :)

I can post some circuit if anyone is really desperate but just know that you're taking away my dream of being the first with a SNES pad weilding Supergun!

Adeptus

I have a SNES to USB chip I bought off a guy on BYOAC forums... still haven't gotten around to assembling the circuit...  :huh:

Apart from a microcontroller chip, it uses an oscillator/clock & a few caps & resistors.

So, it's not exactly what you're after but it's kinda in the neighbourhood...


Segasonicfan

#17
hrmm...I'd actually be kind of interested in this so I could make an input for Saturn controllers on my supergun.  though hacking them looks easier as the aforementioned circuit looks way too complicated for this job and the 74SL673 is mighty too complex for me to build a circuit based on it (I can't even tell which logic levels to input to make sure it has serial in, parallel out- nor can I even find the parallel outputs cause everything's labelled 'Yetc').

If anyone knows a single chip w/clock or similar solution please let me know.

-Segasonicfan
MY WEBSITE: https://segasonicfan.wixsite.com/retro
I design PCBs for retro game systems :)

Segasonicfan

found this:
http://download.siliconexpert.com/pdfs/200.../qd/bu2050f.pdf

Looks like that might be what we need.  but would we need one for each serial line (i.e. 9 for genesis controllers)?  Or is there some way to combine all the serial information into one line?

-Segasonicfan
MY WEBSITE: https://segasonicfan.wixsite.com/retro
I design PCBs for retro game systems :)

NFG

That chip, SSF, is almost exactly what you'd need for a SNES decoder.  Unfortunately it doesn't have a serial out, so you can use a max of 8 outputs. You could use it for the NES but a SNES needs 16 outputs, so two chipes need to be chained.

You still need a clock input and you need a counter to count 8 clocks and latch, 8 and latch, 8 and latch.

You can't use it for the Genesis, the genny pad isn't a serial device.  


Guest

Quotehrmm...I'd actually be kind of interested in this so I could make an input for Saturn controllers on my supergun.  though hacking them looks easier as the aforementioned circuit looks way too complicated for this job and the 74SL673 is mighty too complex for me to build a circuit based on it (I can't even tell which logic levels to input to make sure it has serial in, parallel out- nor can I even find the parallel outputs cause everything's labelled 'Yetc').

If anyone knows a single chip w/clock or similar solution please let me know.

-Segasonicfan
The saturn logic is pretty straight forward:

[img=http://img219.imageshack.us/img219/6459/saturnpaddecoderon3.th.gif]

Excuse my laziness regarding the outputs. All you need for my design (assuming it works) is an oscillator, 7476, � 74139, 4x 74175

Guest_Kyuusaku

I'm the guest (as usual)

Anyways "OMG!" I just actually looked at the thing, it's horrendous! Obviously if you use a 74139 (with active low outputs), you'll need 4x NOTs from a 7404. In the design there are latches, flipflops (74175) are better, but yeah, that's the jist of it.