Sega Genesis To Amiga/C64/CD32 Joypad Adapter (Exclusive)

The Sega Genesis joypad is a cool controller but, as known, it damages your Commodore 64 or your Amiga. So, let's know this “Sega Genesis to Amiga/C64/CD32 Joypad Adapter” well.


INTRODUCTION:
A standard DB9 joystick has one pin for each function (Up/Down/Left/Right/Fire). When you press fire or move the joystick, it simply makes a contact between the related pin and ground.

When it comes to Sega joypads, instead, there is a chip inside the controller which makes possible to use more than two fire buttons and send a signal which is different and “stronger” than the one which a Commodore 64, or an Amiga, is designed for.

Several users straightly connect Sega joypads to their C64s to discover, some days later, that the CIA chip fried.


CIA, SID AND AMIGA DAMAGE:
Furthermore, the chip inside that joypad expects +5VDC from the Genesis in order to operate: well, the +5VDC pin on your Amiga/C64 is wired elsewhere and will short one of the buttons potentially damaging the joypad itself... Was it said that a joystick works by making a contact between a pin and the ground?

The SID has POTY and POTX, which are two inputs used for paddles and available at the two joystick ports. Where the chip inside the joypad expects to draw +5VDC there is POTY and when you press button (C) on your joypad, it will send non-compliant signal directly to the SID.

Last but not least, when you straightly connect a Sega joypad to a C64, simply pressing any keyboard key without even touching the joypad will put a strain on the CIA chip. When the CIA is done, black screen is what you get.


WHAT DOES THAT ADAPTER DO?
The “Sega Genesis to Amiga/C64/CD32 Joypad Adapter” protects your C64 and your Amiga, allowing to enjoy your Sega joypads without having to worry.

It also makes possible to use button (C) on the Sega controller has the second fire button.
The second fire button is something which is rare by itself on both Commodore and Amiga but indispensable for games like “Myth”, “Robocop II”, “Turrican”, “Commando” and C64GS cartridges! Without a second fire button, you would have to press the space bar instead. Hardcore gamers are aware of this issue and hunt for the expensive and rare (but crap) Cheetah C64GS joystick in order to overcome this annoying problem.


TRANSFORM YOUR SEGA JOYPAD INTO A COOL AMIGA CD32 GAMEPAD REPLACEMENT:
Let's continue with another interesting particular: a lot of Amiga titles features two buttons and, since the official Amiga CD32 controller has two fire buttons by default, CD32 afficionados will find this adapter a perfect way to turn any Sega controller into the perfect replacement!

Well, the “Sega Genesis to Amiga/C64/CD32 Joypad Adapter” will protect your chips with custom germanium components, addressing pins to where they should be and isolating unneeded or erroneous pins. Third party Genesis controller should work as well and Sega Mega Drive and Genesis, of course, are the same thing.


PICTURE:
http://img100.imageshack.us/img100/408/webshow.jpg


SEGA JOYPADS TESTED WITH THE ADAPTER:
http://img341.imageshack.us/img341/7...sis1joypad.jpg

http://img849.imageshack.us/img849/5...sis2joypad.jpg


PRICE: €14,00
SHIPPING: €6,00 (EU); €7,00 (Outside EU)


Cheers,
Oge

Nice product but I didn't realize there was any danger connecting sega controllers to the miggy. I thought they just worked

Quote:

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Originally Posted by scrappysphinx

Nice product but I didn't realize there was any danger connecting sega controllers to the miggy. I thought they just worked

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I've heard c64's die of such things, but not the amiga. although I'm reluctant to try. :)

Hello,

Declaring interest for 1 adaptor to Norway!

I've been using Sega Genesis/Mega Drive controllers on Amigas for years and NEVER had any problems using them.

Quote:

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Originally Posted by woodycool

I've been using Sega Genesis/Mega Drive controllers on Amigas for years and NEVER had any problems using them.

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+1, me too, never had a problem once. In fact, we used Megadrive pads almost all the time as we (my brother and I) are not joystick fans. Ive never heard of them causing harm though??

So this this is not really needed ??

EDIT: I've recently got a md2 from these forums, and have actually never used a genesis pad on the amiga before ::)

Quote:

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Originally Posted by Tajmaster

Quote:

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Originally Posted by woodycool

I've been using Sega Genesis/Mega Drive controllers on Amigas for years and NEVER had any problems using them.

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+1, me too, never had a problem once. In fact, we used Megadrive pads almost all the time as we (my brother and I) are not joystick fans. Ive never heard of them causing harm though??

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Last i read was this,

http://www.lemon64.com/forum/viewtop...65d1444b7979fc

on the c64

That's strange - I use a Competition Pro MD pad on EVERYTHING, including my C64c, never had a problem at all.

I gotta agree with the others about there being no issues using Sega controllers on the Amigas...

I really can't comment on the C64 though, and have to assume it depends on the controller being used as to whether or not you fry something...

Ok, interest withdrawn.

strangely though, the amiga and sega do have different pin outs...

http://www.hardwarebook.info/Amiga_Mouse/Joy
http://www.hardwarebook.info/Mega_Drive_Joystick

I don't know how the sega controller would even work on the Amiga, as it appears it won't be getting any power? :/

Quote:

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Originally Posted by AmmoJammo

I don't know how the sega controller would even work on the Amiga, as it appears it won't be getting any power? :/

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But guess what .... it does work!
Only buttons B and C work (as button 1 and 2)
Sega MegaDrive pads work on nearly anything that adhears to the Atari joystick standard (C64, Amiga, Spectrum 'Kempston' interface etc.) however I've had some problems with MegaDrive pads on the following systems:

Atari ST/STE
Atari have put an interesting feature in the ST meaning anything that is not 100% compatible with the Atari standard (so the MegaDrive and CD32 pads) will not work AT ALL - nothing happens

Amstrad CPC
The Amstrad CPC has only one joystick port (to access two players is usually done through the pass-through on an Amstrad JY-2 joystick or with an adaptor) - anyway, when I connect a MegaDrive pad to my CPC, it sends both Player 1 and Player 2 signals at the same time, so it controls both players - it makes playing Gauntlet impossible (you have player 1 and 2 at the same time) - also with an MD pad connected, I get interference when typing (start getting random joystick commands appearing in the middle of BASIC commads etc.)

The following one explains why Sega Genesis Joypads cause damages on C64s.

Quote:

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This is because joysticks (which the game ports were intended to support)
either pull the lines low (when active) or are an open connection (when
inactive). This latter condition allows the lines to be pulled low by other
sources (they keyboard for example). Sega gamepads, on the other hand, pull
inactive lines HIGH. Now if you press a key on the keyboard with one of
these devices plugged in, one source is pulling the line high while another
I/O line (cross-connected through the keyboard) is trying to drag it down.
This can put an extra strain on the CIA chip, as the circuit wasn't
designed to deal with this kind of situation.

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About the Amiga systems, here it is what I've discovered when I was creating this project.
1) A Sega Joypad acts differently than any standard Amiga Joystick because of the above mentioned explanation (pulling inactive lines high instead because of the circuit inside of the Controller);
2) A Sega Joypad connects "Button 1" where on the Joysticks +5VDC is expected
3) The pulling of these lines is driven by a Logic IC according to an input signal. Instead of that input signal, there is +5VDC coming out from the Amiga
4) The TTL signal is different and stronger than the designed one


Surely an Amiga has not a CIA, but there is an uncommon signal throwed at the Amiga when you use a Genesis Joypad. Being Amigas more rugged don't mean it won't cause harm to the hardware: the Controller was made and intended for a completely different system.

In the past CMD modified Sega Genesis Joypads when it comes to C64 and Amiga usage and I guess it wasn't for fun.


Cheers,
Oge

I've made a deeper description which explains everything.


Cheers,
Oge

Some users there on Lemon64 reported issues with Sega Joypads straightly connected to C64s:

Quote:

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Originally Posted by dink

Some more proof that Sega controllers harm the '64 - I had repaired for a friend, a C64 which after using a SMS (I'm pretty sure it was SMS, but it could have been a Genesis/MD as well) controller for quite a while, caused half of the keys on the keyboard to permanently stop working. The fix was to replace a chip (I wish I could remember which chip, this was back in 1989!) Then sometime around 1994, another good friend had been using a Genesis/MD controller with his C64C for quite a while, he was the kind of person to never turn the computer off, you know, just leaving it sit there with a game waiting, with the monitor off. Sooner or later joyport 2 completely stopped working, and his parents had gotten an IBMPC around that time, so he never did get it fixed. So the moral of the story is, never directly connect a SMS/Genesis/MD controller to a C64/C64C directly, because sooner or later, you're going to fry some chip in your beloved computer.

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Cheers,
Oge

For years I used mega drive pad on amiga

Have you tried your adapter with a Sega Master System joystick/pad?

Is it possible to have a master system pad working such that one button is fire and other button is the other button for amiga?

Currently I have this quite nice stick here: http://www.amibay.com/showthread.php...ystick+awesome

But both "A" and "B" buttons are just your old regular fire button. Still need spacebar for Turrican :(

Quote:

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Originally Posted by Mendel

Have you tried your adapter with a Sega Master System joystick/pad?

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I've just tested it. Yes, it works.

Quote:

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Originally Posted by Mendel

Is it possible to have a master system pad working such that one button is fire and other button is the other button for amiga?

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When it comes to Sega Genesis I & II Joypads, button "C" is addressed as the Second Fire Button through the Adapter object of this thread.

A Sega Master System Joypad is a bit different, so I should esamine the PCB in order to see if it has to be modified internally. In other words, you can get rid of the need of pressing Space Bar with Turrican using a Sega Genesis Joypad connected using the Adapter object of the current thread.

I hope it's clear. :)


Cheers,
Oge

Hi Oge, have you tried the adapter with Atari STe?

Thanks,
Jim

OMG!

I almost had a heart attack when I've started read this thread of yours!

I'm (ALSO) using md pads on amigas for years!

for God shake man...!!!:wooha: just type "md pad kills C64 CIA chip" etc

Quote:

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Originally Posted by jredfern

Hi Oge, have you tried the adapter with Atari STe?

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Not yet, Jim. But I'm sure that it will work as the Adapter standardizes the connections in regards to the DB9 standard.

In other words: since a C64 Joystick will work with an Atari STE, a Sega Gamepad connected through this Adapter will work as well.. :)


Cheers,
Oge

Hi oge, interesting reading, I dug out the issue of Commodore World with the original C64 schematic in and had a think, I just knocked this up in paint (attached) is this the same as what you're building?

What diodes are you using? 1N4148?

AFAIK there's no reason to be putting diodes on any of the other lines is there?

Thanks,
Paul

The adoom readme says to put a 470 ohm resistor between 5 and 7 once swapped, but would this not have the effect of putting it into permanent +5vdc mode?

Ok, a bit more thinking/reading and I think I understand better now - the 470 ohm resistor is to pull up the select line if POTX was left floating, but if set POTX will easily override the 470ohm pull-up.

Also, 1n4148 diodes will have too much forward voltage and germanium type 1n34a are expensive/harder to come by (loads on ebay) but Schottly type BAT85 should be fine.

So the last thing i'm wondering is if a diode is needed on the select line, and if added just for good measure would it stop anything working?

Updated schematic attached.

I used a third party megadrive pad on my A500 for years of heavy gaming and there was no problem at all.

Interested on behalf of a Czech friend.

Postage to Czech Republic? If cheaper, in one package for the two adaptors.

For anyone interested, I made the adapter according to my above schematic (apart from I put the diodes in the Amiga end of the cable) and it works fine.

Back in the day when I had a Sega Genesis I used the game pad with my C64, a lot. The only problem I ever had is that one of the buttons (don't recall which) reset the C64.

Quote:

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Originally Posted by bigshowpl

Also, 1n4148 diodes will have too much forward voltage and germanium type 1n34a are expensive/harder to come by (loads on ebay) but Schottly type BAT85 should be fine.

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I was able to find and use the original 1N4148 diodes. They are expensive, out of production since years and hard to find but they seem to work better than equivalent diodes.

It took time and efforts in order to find them.


Cheers,
Oge

Here's another report from a user of a 6-button Sega Genesis joypad (original one) for YEARS on at least 3 Amigas with NO problems. I may understand the problem on C64 computers and POTX/Y lines , but I am pretty sure I tried one and nothing happened. But then again, I never used such controllers in my Commodore.

Now, I once had a ****ty counterfeit Sega 6 button pad, and this one DID act strange both on the Amiga and C64. So I guess the rule of thumb is to go for official pads, and some times, ascertaining a pad is original is complicated.

Do not meant to derail the original poster's thread, as he makes mighty good cables, but saying there are problems with Amigas is unnecessarily alarming and also not really true.

Payment sent for one unit.

Would like to order one of these. Not allowed to PM you since I'm a new member.

How do I go about getting some money to you :D

I would like to ask you a couple of questions before purchasing, I sent you a PM.

Hmmm, I have used a MD pad with my A1200 since 1996 (Megadrive 2, with the red start button). You HAVE got me worried though.
Is this really a danger to Amiga's? I know A2000's and A4000's seem to have a lot of port troubles...maybe this could be a possible reason?

I'm interested in buying 1 adapter. Please pm me with the details.

payment sent x2 adapters

Quote:

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Originally Posted by pr649

payment sent x2 adapters

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Items received!

Many thanks

Up. :)


Cheers,
Oge

Do I need this adapter for Sega Master System controllers as well, or are they safe?

I have mod'ed a Sega joypad to have a good 2-buttons joypad for my Coleco.

Not hard to mod. If I wouldn't have the "Playstation 2 adapter" I would probably do the same for the Amiga.

http://www.youtube.com/watch?v=MoYsJJiU0jA

:p

I would like to Buy 2 or when available, 3 Adapters. I guess its also saver to play Atari 2600 and other 9Pin Consoles with the Adapter. Because, I realy like the Mega Drive Controller for playing Amiga, Commodore or Atari.
The hunt for good Joysticks is annoying and since the Sega Controllers work like a charme, i would prefer this solution, just to be save.

Quote:

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Originally Posted by bigshowpl

Ok, a bit more thinking/reading and I think I understand better now - the 470 ohm resistor is to pull up the select line if POTX was left floating, but if set POTX will easily override the 470ohm pull-up.

Also, 1n4148 diodes will have too much forward voltage and germanium type 1n34a are expensive/harder to come by (loads on ebay) but Schottly type BAT85 should be fine.

So the last thing i'm wondering is if a diode is needed on the select line, and if added just for good measure would it stop anything working?

Updated schematic attached.

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Is that how this adapter is done? 1n4148 are ok? I have lots of those diodes at my work.

Quote:

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Originally Posted by Oge

Up. :)


Cheers,
Oge

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Still doing those adapters? I'm interested. Just bought CD32 with one loose competition pro pad. Are those diodes necessary? Of I only pry up my genesis pad and swap those 5 & 7 pins and add 470r resistor, is it ok? Two buttons will work?

hello I wanted clarification about
I use the pad I used Megadrive and Master System on amiga at least 5 years
I have never had any broken components therefore do not understand why we want this adapter otherwise you can 'damage the Amiga and its components!
please can you explain me why it takes your adapter
Let me be clear I do not want to insinuate anything delal your sale but only to understand why

Sono interessato all'acquisto

posting interest in a set of two :thumbsup:

cinghiale748 sorry this is a world wide english written forum please edit your post to english thankyou

Interest withdrawn. Thank you very much bigshowpl. I soldered an adapter according to your Scetch and it works fine!

I totally agree with this Sega Genesis to Amiga stuff.
You are risking damages to your CIA even if it has never occured so far thanks to the tolerance of your chips.
A quick search on any Amiga board will let you know that CIA are a weak point of Amiga mobo, so there is no need to help them to die.

I am interested in one of these adapters please.