An alternative solution to my GDROM drive problem :)

OldFoo · Post by **OldFoo** » Thu Dec 27, 2007 9:15 pm

Im currently playing around with some Naomi bits and i came to the point of needing a GDROM drive. As most of you know they are becoming quite expensive due to Sega ending there production.

I know some of the DC drives are compatible so after spotting a certain set of pads on the DIMM daughter board i set about finding just how compatible they are..

Well after a bit of squinting and a couple of traced out solder bridges later .. ITS ALIVE !!!

OldFoo · Post by **OldFoo** » Thu Dec 27, 2007 9:33 pm

Have you connected the GDROM mech directly to the DIMM board? :smt017

OldFoo · Post by **OldFoo** » Thu Dec 27, 2007 9:41 pm

Yes , with the addition of the GDROM connector scrounged from a Dreamcast along with a handful of passive components. You have to add an extra power connector aswell but Sega already quite kindly added in the solder pads for that too .. a standard Molex pinout.

OldFoo · Post by **OldFoo** » Thu Dec 27, 2007 11:01 pm

sonic 2 carts do have a use after all

OldFoo · Post by **OldFoo** » Thu Dec 27, 2007 11:20 pm

awesone!

OldFoo · Post by **OldFoo** » Thu Dec 27, 2007 11:21 pm

maxchainsplendid wrote:sonic 2 carts do have a use after all

The Shenmue CD Box gives his support too!

MrSporty: Can you take a more detailed picture of the area where you have done your modifications, please?

OldFoo · Post by **OldFoo** » Thu Dec 27, 2007 11:48 pm

http://img244.imageshack.us/img244/7075/dscn0659zy1.jpg

Appologies for the quality but my camera is crap and with the amount ive consumed over the holidays im suprised its so clear .. lol

OldFoo · Post by **OldFoo** » Thu Dec 27, 2007 11:54 pm

That is so cool, I cannot wait for more details on how to do this. Nice work as always MrSporty.

OldFoo · Post by **OldFoo** » Fri Dec 28, 2007 10:39 pm

this is very interesting,you may have found out something that has been giving me a bit of trouble :smt004

OldFoo · Post by **OldFoo** » Wed Jan 02, 2008 8:23 pm

Heres a little update for Ace and others that asked for the info.

Referring to the above picture you will need to add the following.

A power connector to the top left. I used the standard hard drive psu cable so i guess you could use a molex connector but it will need to be mounted vertically as it butts up against the DIMM memory. Pinout is 1-4 .. +12 0 0 +5

Below the psu are solder pads for 7 inline filters. They are 3 pin devices with the center pin being GND. I linked them out with wires (indicated in green) but if you use bare wire like i did .. make sure they DO NOT touch the center pins at all.

The 4 red boxes close to the connector are 330 ohm resistor packs. I indicated a fifth one to the right so you can see what they look like. They can be scavanged from the lower side of the Dreamcast mobo you would be getting the connector from.

The 11 blue links are resistors. Again i indicated a similar part to the right. Impatient and rough arsed as ever i just linked each one out with solder bridges and wire wrap wire.

And finally the connector just sits on the pads designed for it. Its not keyed so you can mount it either way. It has 2 metal mounts either end that can be desoldered seperately to aid removal. You WILL need to use smd tools or me particularly handy with a scalpel.