Tuesday 28 August 2012

HOW TO OVERCLOCK SEGA MEGA DRIVE 2 / GENESIS 2

Hi Everyone,

I thought I'd make a post on something that had been playing on my mind for a couple of months. And the thing that had me thinking and questioning was "why does no-body overclock the model 2??". Sure I've seen the Screen Savers video on youtube where they describe how to do it by pinching the clock speeds from the cartridge slot. But I was never convinced with this way of doing it and the guy in the video doesn't get it to work that way. And the way they show the overclock is on his model 1, which is what you find all the overclock info on. Overclocking the model 1.

Well, the way described in the video involves using quite long wires to do the overclock which from my understanding would cause problems because of the length of them. In the model 1 overclock video I've followed Damomonster explains that wires longer than 3 inches will cause problems with the overclock.

Last week I managed to find a very rare video on youtube of someone claiming to have overclocked their Genesis 2, and the way they did it was the same way I'd overclocked the model 1. Using a 10mhz crystal on some vero board mounted on top of the processor. But since then they have taken the video down, so now there are none. Except mine now I think :-P

I've been thinking that if you know which pin to lift on the model 2 processor then in theory you can do the overclock the same way as the model 1. You'd just have to know where to tap your +5v from and where a nice close point would be to get Ground.

Well its pin 15 that you want to lift on the processor, just like on the model 1. The processor is the same as the model 1 but in a smaller form factor. Now we know which leg to use we can begin ;-P

Right, I think I'll write this point for point.

THE GUIDE :

(1) -- first thing to do is to make the 10mhz overclock 'package' described in Damomonster's great step-by-step guide :



A thing to remember is keep your wires nice and long to begin with so you can trim them down to size when you come to mount it and hook it up to the processor.

(2) -- now you've got the 'overclock package' made and insulated up with electrical tape and some nice long trim-able wires we can go to the Mega Drive 2 (Genesis 2). Open the sucker up by removing the 4 screws underneath, then remove the inner metal shielding. For me I find it easier to take the whole motherboard out of the case so you can rotate and investigate it easier.

(3) -- Now the board is out of the case you need to find the processor, which is the square chip in the back right hand side of the board behind the cartridge slot.
The next step is to find Pin 15. I've marked this on the photo in pencil. Sega have been nice to us and have numbered the pins on each corner of the chip. You can see Pin 10 on the bottom left of the chip, so we count across to the right and find Pin 15.

(4) -- The next step is to get the soldering iron out and get it warmed up. I don't know how much heat the legs can take on the processor as they are very small and fiddly to get to so I would recommend a lowish wattage soldering iron with a thin tip on it just in case. I used a 15w Antex for doing this with a small wedge shaped tip. A pencil shaped tip would be even better I think.

(5) -- Now the soldering iron is warmed up and we have Pin 15's location we need to warm the pin. I did this by pressing onto the side of the chip and the soldering pad area and got a thin Pick tool behind the leg. You need to be very careful here as the legs are deceiving! They aren't sticking out from the chip, thats the soldering pad that gives it that look. The leg is actually wrapped back and under the chip to raise it from the PCB. To give some ventilation I assume.

While heating the leg gently wiggle and bend it outwards. Remember, take your time so you don't pull the solder pad up at the same time!

You should end up with the chip looking like this :
You can see Pin 15 now lifted free from the board and the solder pad is still underneath.

(6) -- Well done!! That's the scariest part done! The next steps are delicate still but that was the hardest bit.

Now we need to cut 2 wires, strip the ends and tin them. The wires want to be just long enough to reach the back of the case.

This is the most direct and shortest route for the wires to go. We need to keep the wires as short as possible but still able to reach our Double Pole / Double Throw switch so that we can still switch between the stock speed of 7.6mhz and 10mhz. This way we can still use the Mega CD and 32x because we can revert back to stock speeds.

(7) -- Now we carefully solder 1 wire to the solder pad under Pin 15. Be very careful not to tug this wire too much or too hard. You could still pull the solder point up and that would be a pain.

(8) -- Next we solder the other wire to the leg of Pin 15. Add a little solder to the leg first so that all you need to do is gently press the wire against the leg using your soldering iron to get them to melt together.

(9) -- Now we are at a stage where we can follow the rest of Damomonster's overclocking video BUT FIRST we need to know where to tap the +5v and the Ground from as these are going to be different to the ones in the video as that is a Model 1.

In the above photo you can see 3 capacitors. There are 2 to the side of the processor, 1 to the left and 1 to the right. These 2 are the ones we will use to get our +5v and Ground from. They are really close which keeps our wires short and very convenient.

Again Sega have made it easy for use because they have marked the + side of the capacitor so we know which side to get +5V from (the + side) and the none marked side is Ground.

Here is the second part of Damo's overclock video to follow :



The main thing to follow from this video is the Double Pole / Double Throw (DP/DT) switch set up and the LED wiring.

(10) -- Now you've followed his video you should end up with a switch looking like this :
 In this photo its the overclock wiring you can see on the top. Blue = 10Mhz, Orange = Pin 15 and Green = 7.6Mhz Stock speed. The row of pins below are Orange = Red LED colour, White / Blue = +5v from the Overclock package, White / Orange = Green LED colour.

(11) -- In the photos you can see that I've just electrical taped everything in place to test it out. You should now have something that looks like this :

(Ignore the mass of wires on the left, that is from my A/V port retro-fit)

Now we can go and test that the overclock works. :-D

Below is a video of my Mega Drive 2 showing the overclock mod and it working on Sonic 2. It was tough to film as I used my phone and I couldn't mount the phone so you can see me playing Sonic 2 (which might be a good thing haha) and excuse the sniffing and coughing as I have a cold ;-)



(12) -- Now you've tested its worked you can squeeze some hot glue over the Pin 15 area. This will make sure that the wires will not get tugged and pull the leg off the processor or pull the soldering pad up. You do this stage once you've tested it as this is a perminant step. Also squeeze some hot glue onto the top of the processor and stick the overclock package on-top. this will stop it ever moving around.


AND WE'RE DONE! :-D Your Sega Mega Drive 2 / Genesis 2 is now overclocked! You can enjoy Sonic 2 in all its none slow down glory as well as a whole host of games that push the stock clock speed a bit too much passed its limit of 7Mhz.


So there you go. I haven't been able to find any real guides on how to do this to a Mega Drive 2 especially one with photos and video of it working. So I decided to make one if this mod worked out, which it did, so I did. :-)

I hope you get it to work out if you give it a try. Just take your time lifting that leg up and you'll be fine. If you have any problems leave me a comment and I'll try to help you out.

Cheers

Porl''

Wednesday 22 August 2012

SEGA NEPTUNE - CASE CONTINUED...



Howdy pardnurs,

A quick Neptune update for ya'll...

Well I'm back of my holiday to sunny bournemouth and got a bit more inspired to try and finish off my Neptune case. Before we went on hols I'd sprayed up the case as it was in matt black to get an idea of how it will look in Sega Black plastic and when I looked at it earlier I thought "dang! it looks pretty cool!".

So I've got my pen and paper out and carried on trying to figure out how to sort the buttons out as they are relocated further up the case now. Once they are working and clicking away it will be in its final stages I'm sure. :-)

Here are a few photos of the Sega Holy Trinity I took earlier in the garden. I've got some more filling and sanding to do on the case too. That seems to be a bit of a never ending job with this case. The end is hopefully in sight though.

Catch you later

Porl''










Tuesday 21 August 2012

CAPCOM CPS-1 : THREE WONDERS

Well my last post was about my lucky haul of CPS-2 games and A-board and for this hopefully quick post I thought I would write about the CPS-1 game I have. One I was really excited to make a trade for!

When I was a kid there was an arcade just on the outskirts of the center of my town in Burton in a side room of a newsagents. Well this Newsagents had 2 side rooms, the front smaller room was rented by a guy who ran it as a computer games shop and it had ace Ocean and US Gold posters in the window and was where I excitedly bought Street Fighter 2 on the Commodore 64 which was ultimately a disappointment, but that's another story.

The Second side room was still rather small but on all three walls, kind of arranged in a horse-shoe shape were about 6-8 arcade machines. All 10 - 20p a credit and the games were regularly updated every month or so.



Well one month this wonderful Capcom 3 in 1 game turned up in one of the machines. A really cool platform shooter called "Midnight Wanderers - Quest for the chariot". The artwork grabbed me straight away. I loved the characters and the graphical style! And I remember it being rather hard!


The second game which I didn't play too much because I was always popping my 10's and 20p's into Midnight Wanderers was called - "Chariot" which was an R-Type style side-scrolling shoot em up. This game was essentially Midnight Wanderers 2 as it continued the story of Midnight Wanderers


And the third game which I never played, which was a shame because I have now found out its a very cute and fun puzzle game called "Don't Pull". You play as a cute little animal, a rabbit and a squirrel I think it is running around a level with a similar look to bomber man and you push the blocks around to squash the enemies and to find bonuses.


So, CPS-1....whats that mean then? Well the CPS-1 stands for Capcom Play System-1 and was Capcoms way of moving away from creating a dedicated game board. Where they have to manufacture 1 be-spoke board design per game. The CPS-1 was a way of making a board that was more like a console in a way. You have several parts to the game PCB, A, B and C boards. And changing the B and C boards (with the appropriate ROM chips) you can play different games. This I'm sure saves on manufacturing costs on producing the PCB's. Also the CPS-1 is JAMMA standard so you don't need anything special with it, just plug in your JAMMA connector and your away. That is unless your playing Street Figher 2 :-P where you'd need the kick harness to get all the 3 strengths of kick working.

So if your CPS-1 board stops working you can sometimes repair them by replacing the different boards. Also, you can change the game by flashing different ROM info from Mame onto the chips and play say Final Fight or something like that on the 1 CPS-1 setup. But I'm sure that's a bit of a pain in the bum to do all the time.

Anyway, I had a Sega Rally Model 2a complete board (in cage) but couldn't do anything with it because Model 2a doesn't run on Supergun's. Well, its a big job to get them to work apparently and then I read that you need a certain frequency monitor for it to run, and obviously steering wheel, gear changer and pedals. Something I'm not going to get any use off.

I'm on a great arcade forum called Arcade Otaku and I got chatting to a dude about half an hour away from where I live who has a Sega Rally machine that he was willing to test my game out on. So I knew it worked, and if it worked and I was interested wether I would trade it for his 3 Wonders CPS-1 game. Well I jumped at the chance to have a nose at someone elses arcade collection and man was I impressed!!

Once I saw the CPS-1 board and how blumin clean it was I snapped his hand of to trade for it. Its the cleanest looking PCB I've ever seen and couldn't wait to get home to play it on my Supergun (after I had a quick go on it on the guys Capcom Cute cab).



Does it still grab me like it did when I was a kid? Yep it sure does! The art style is still fantastic and it's still rock solid! I've since completed all 3 games but I needed to add credit after credit to do it! And without my girlfriend being player 2 on Don't Pull I don't think I would have completed that! haha.

Next is to challenge myself to complete the games on a limited amount of credits. I think it will be 5 credits a go. Take it back to when I had limited credits due to pocket money rather than eliminating the challenge by constantly pressing the credit button on the Supergun. :-P

Porl''