A "Scientific" approach to mod a 64pin saturn

First of all hello to everyone. I'm totally new to the Saturn scene, i'm a ps2 / xbox / GC experienced installer....now trying to obtain a chipped saturn. This is my situation: recently i bought 2 chips from racketboy (a very kind person :) ) to install into 2 saturns model 2.

On my 32pin saturn it works flawlessy....

On the other i just realized it was a 64pin saturn...so unmoddable.....or not?.....Let's try to find a solution....

I've tried to use the 32pin optical board instead of the original 64pin one. As a result game were succesfully recognized but only at the machine start-up with disc already inserted. No way to boot on the player-screen.

So i think we can mod 64pin saturn even if not so good (e.g. by inserting the disc before starting the machine) but the problem lies in the A signal. So i made some investigation......

When we link A+B or take the A signal from the 14th pin (is'exactly the same....both B and 14pin-for32pinIC or 8pin-for64pinIC are the same signal) we are taking a clock signal coming from the MN662724 IC.

This IC is present in both systems and outputs a 4Mhz or 8Mhz clock in accordance with the level of the MSEL pin (pin79)....so where is the difference then?

In 32pin board we have a M37477M8 IC that can work up to 8Mhz...so i think 8Mhz are taken on 14pin when we use a modchip on a 32pin saturn.

In 64pin board we have a HD6433612 IC(h8/300L compatible) that can work up to 4Mhz...so i think 4Mhz are taken on 8pin when we use a modchip on a 64pin saturn.

So...how about a solution?

A possible solution COULD be some way to generate 8Mhz....or by a frequency doubler...or by adding a resonator and other discretes to generate this clock signal...i dunno....i'm not an EE.

So i ask: if u have some sort of electronic experience help us!I'd like to know if my theories are wrong...maybe someone like Pinchy can understand where the problem lies. I try contribute with my test/experiences/soldering skillz.

Last minute info: I've tested the other model2 saturn (the 32pin IC one) and if it's powered with tray open it cannot recognize backups.....the same as the 64pin model with 32pin board exchanged.....bah!
Just another info:

the model2 64pin saturn has a separate daughter controller board like this thread

I installed the chip bought from racketboy with the A+B method and all (originals) were well recognized....i was able to listen to backups with audio tracks too. If i disconnected +5v or A or twist the lens cable it gave to me the well know "checking inserted disc" error with cd no spinning.
Very nice to see someone investigating into

this matter.

I have a Chip + 64 Pin drive to mod here,

so I will start checking tomorrow.


my saturn will recognize cd's as audio NO MATTER what you do (twist cables,change gridges,trace wire/ab,it'll still give me its audio screen...and the muscis does play) weird

any news?

However i've checked the "mod behaviour" and i've seen it's usual that the mod doesn't work if saturn is powered on with cdbay opened.

I've replaced the 64pin board with a 32pin one and the mod worked flawlessy as the "normal" 32pin saturn....because the "cdbay opened" issue happens both in original 32pin saturn and in the 32pin "swapped" one.

Hope to be of some help.
I have a 64 pin PAL model 2 saturn. I modded mine with a V2 modchip board and an action replay 4-in-1 from this guy :Rob Webb

My saturn now works perfectly and reads everything i throw at it! :thumbs-up:
Originally posted by Otaku_punk@Sun, 2005-05-01 @ 12:35 AM

I have a 64 pin PAL model 2 saturn. I modded mine with a V2 modchip board and an action replay 4-in-1 from this guy :Rob Webb

My saturn now works perfectly and reads everything i throw at it! :thumbs-up:

[post=133413]Quoted post[/post]​

Others have tried to use the modchips from that place and have come up empty so those chips are not full proof either.

This hit and miss that we seem to get with 64 pin Saturns leads me to believe that there might be different versions of 64 pin Saturns. Perhaps certain model 64 pin saturns have a better chance of working or ones manufactured in a certain place?

Maybe not though, it just seems odd to me that there are so many inconsistencies with the 64 piners. Some people can get them to work flawlessly, others work about half the time after opening the CD door and closing it again, and then some cannot get them to work at all.