Dreamcast VA0 mainboard and power supply schematics scans.

[l_oliveira]

From Tec Toy.
Sadly there is no sign of schematics for the GD-ROM drive...

But I think this will make a lot of people happy...

Grab it here:

http://www.4shared.com/dir/13490883/...MCAST_VA0.html

[-=FamilyGuy=-]

Wow, sweet! *Going ot the store and buying parts to do a DC from scratch ..."

Seriously that's pretty damn interesting.

FG

[TmEE]

total awesomness :D

[alphagamer]

awesome, thanks

[Evangelion]

IC501 is a 27c160 PSOP so can we use equivalent component like 27c160 DIP42 ?

[neoblast]

Woah, are these form tectoy?
They are just awesome...

[raylyd]

cool will help in any fault finding

[l_oliveira]

An interesting idea I had just from looking at that schematics was a "dual bank" dreamcast flash. As you guys probably noticed already, the FLASHROM chip is just a 256kb flash with A17 tied to VCC. Tieing that to GND instead will give you another 128KB of flash, without bootblock protection even. Using that, you preserve the original flashrom configuration at the other part while having a fully writeable flashrom for experiences/testing at the other part of the memory.

Should the Dreamcast "brick" you just switch back to the original page of the flash, boot a tool disc (such as the region change disc) and use it to repair the second half of your flash (as the original one will be kept with it's original write protection, no damage will happen.

I'm glad you guys liked it.

[Storm]

Useful, thanks!

[Dreamcast]

Here is a PDF I found today listing the different chipsets used: http://www.chipworks.com.tw/resources/toybox/Sega_Dreamcast_Game_Console-BPT.pdf

[-=FamilyGuy=-]

Here is a PDF I found today listing the different chipsets used: http://www.chipworks.com.tw/resources/toybox/Sega_Dreamcast_Game_Console-BPT.pdf

This pdf document is recognized as faulty by both my Windows Office Software and Google Docs ...

Seems like some REALLY interesting info though.

Anybody who can open it could make an viewable version of it? It's be appreciated.

Thanks,

FG

[Dreamcast]

Do you have Adobe's Acrobat Reader installed? If so, try that. That's what I used. I also converted the PDF pages (15 in total) to lower resolution JPGs (the pages in the PDF are fairly high resolution) and hosted them here: (view page)

From a technical standpoint, there really isn't much in terms of information we couldn't get from looking at the board, but it's a nice precompiled guide to have handy.

[TmEE]

I had no trouble viewing it... its not too useful IMO.

[-=FamilyGuy=-]

Do you have Adobe's Acrobat Reader installed? If so, try that. That's what I used. I also converted the PDF pages (15 in total) to lower resolution JPGs (the pages in the PDF are fairly high resolution) and hosted them here: (view page)

From a technical standpoint, there really isn't much in terms of information we couldn't get from looking at the board, but it's a nice precompiled guide to have handy.

I actually have Acrobat Reader ... Maybe my download was corrupt and that'Ms why I got an error with both office and google docs. Thank you for the upload though!

FG

[OzOnE]

Not sure if this has been posted before...
I thought it was so cool (and relevant), I had post it...

http://yam.20to4.net/dreamcast/va1.html

[runkthepunk]

Well as you are aware I know nothing about this sort of thing but even to me that looks useful/cool

At first I thought 'oh its just a picture of the DC board' then I moved my mouse over the text and the circles lit up telling me where things are and it made me happy!

I am a simple man.

[Druid II]

From Tec Toy.
Sadly there is no sign of schematics for the GD-ROM drive...

But I think this will make a lot of people happy...

Grab it here:

http://www.4shared.com/dir/13490883/...MCAST_VA0.html

Could someone please reupload these on another host, 4shared is completely useless and I get tiny unreadable pictures.

[LeGIt]

Not sure if this has been posted before...
I thought it was so cool (and relevant), I had post it...

http://yam.20to4.net/dreamcast/va1.html

Arf that link has just saved me a great deal of effort. Shame I already stripped a few DC boards and mapped a number of the test points before noticing it.

I had to strip them anyway to drill out the SH-4 pins to make a jig for my RAM hack, but if I had known about the link I could have perhaps been more careful with the first and spared the last couple the same fate.

Nevermind as I have labelled some of the test points in more detail and painted the individual traces so I can see exactly what goes where too.

[dclover56]

Well, i do have an idea to One up the original GDROM format with DD (Double Density), and DL (Dual Layer) discs with a improved spec in new Dreamcast S units, with older dc's needing a special drive