Discussion DreamCast R&D and Documenting

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is there anyone that has experience with dreamcast programming I know this would probably be difficult but is there anyway we could create a custom bios to bypass the fan. We already need one to bypass the disk drive so it would be useful if there was a way to not check for the fan. Just an idea I had been thinking about.
 

Shank

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is there anyone that has experience with dreamcast programming I know this would probably be difficult but is there anyway we could create a custom bios to bypass the fan. We already need one to bypass the disk drive so it would be useful if there was a way to not check for the fan. Just an idea I had been thinking about.
Im sending 2 dreamcasts and a few accessories to @Aurelio, so its only a matter of time before he patches out the GPU.
 
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Might as well upload these for posterity.
REDACTED
If any Compendium-style layer work is to be done, they might come in handy.
 

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Got it. It didn't say edited by a moderator or anything.

For anybody who was unaware, schematics for the Dreamcast are floating on the internet, and can be accessed through a bit of googling. But since they are confidential files, @Aurelio has advised us not to post links to them here on bitbuilt.
 

cheese

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If you guys wanna sand it, that's your work, you can post that here. But leaked schematics are best for PMs, or offsite. If any of you have a dead dreamcast, a sanded board would probably help, and a compendium can be made out of those sands/scans.
 

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If you guys wanna sand it, that's your work, you can post that here. But leaked schematics are best for PMs, or offsite. If any of you have a dead dreamcast, a sanded board would probably help, and a compendium can be made out of those sands/scans.
@Aurelio would a compendium be of any use for this? I think it's a 2 layer board so i don't know if that would actually offer any help. I'd be willing to do so if it was.
 

cheese

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Well, I doubt you can do much of any trimming without custom parts or pcbs, since the board is pretty compact for what it is...But, if you wanted something similar to a schematic for the board, if you are so inclined to make a custom PCB or a board bend of some kind, you would need to sand the board and post the scans if you wish for your work to be posted. You can post guide suggestions if you don't include anything that you don't own. If you're curious if something is acceptable, shoot a PM to me or another staff member, and we will let you know if it is acceptable to post.
 
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Sorry everyone for posting without checking the rules. :oops:

@Gman did some work on the Dreamcast back in the ModRetro days. Kinda creepy, Gman, but I scoured your Photobucket and found your board sands and the possible trim diagram you made. Since they're not my photos, I won't post 'em unless you're cool with it.
 

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Sorry everyone for posting without checking the rules. :oops:

@Gman did some work on the Dreamcast back in the ModRetro days. Kinda creepy, Gman, but I scoured your Photobucket and found your board sands and the possible trim diagram you made. Since they're not my photos, I won't post 'em unless you're cool with it.
Naw, its all good. Its not really written out in the rules, its a weird circumstance. I made the same mistake initially and Aurelio deleted it as well.

As for @Gman's photos, I say post em here. Knowing him, Im sure he wouldn't mind as long as he is credited.
 
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I took a look at his Photobucket to see if I could find it and I did however I noticed that in the trimming guide he showed that some vital components can be removed. I might just be misinterpreting what the diagram is showing but I still don't know if its accurate
 
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Edit: Photo of trims not really legit.

I've looked into the two ICs at the top of the board (one's got eight legs and the other has 14) and they're both audio-related. The bigger one is a custom audio ADC, but it has some generic cousins whose data sheets I'll be investigating. The little one is just an op-amp.
 
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Shank

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I took a look at his Photobucket to see if I could find it and I did however I noticed that in the trimming guide he showed that some vital components can be removed. I might just be misinterpreting what the diagram is showing but I still don't know if its accurate
Agreed. I just dug through myself and none of the Dreamcast mobo pictures are of any value. They assumed trims are incorrect and the other photos are not good quality. Ill probably take some good photos and upload them at a later date.
 
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I'll see if I can sand down my motherboard and scan it at some point in the next few weeks. There are just lots of traces jumping back and forth between the layers that need to be mapped.
 

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We have schematics, so that may not be necessary. Coming from someone who really, really hates taking no for an answer when it comes to "can this be done?", Im sad to say that there just isn't much that can be trimmed off of the dreamcast. @Aurelio and I spent a long skype chat discussing the possibilities of dreamcast trimming, and it just isn't that promising. Using aftermarket parts and crazy rewiring, a bit could maybe be cut off the top, and the edges could maybe be trimmed maybe just past the ground plane, but thats about it.

For now, what we should be concerned with is the minor details other than trimming that still need to be worked out. We need to find the most effective way to accomplish things such as removing the fan, outputting video, loading games, powering the device, dissipating heat, and powering the RTC. While not as flashy or impressive as board trimming, these are all issues that need to be worked out for any decent portable, trimmed or untrimmed. If any of you guys are interested in helping, shoot me a message and Ill let you know what you can do to help.
 
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I know this is a wild necro-bump, but I really need the help. I'm from the Modretro forums (Username: Sonic4freedom). I'm currently working on my 4th DCp, but I'm SICK of that damn controller board for the joysticks, I looked through this thread and wanted to know where were we on getting the pinout for the controller and fan and getting rid of that controller board for the joystick all together. My DC already has the CF Mod and the region free switch. Is there already a diagram or scan for it? If there is I couldn't find it. I've been doing this since 2008 on the BH forums and never once came across it. Any help fellas? You guys seem to have a way better grasp on this.
 

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i'm on mobile now but hit me up on discord/pm.. i might have something that helps you out (also check the latest posts on my dcp worklog for some controller stuff)
 
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I actually just ended up continuity testing it, mapping it and tested it and it works. I'm now able to wire the controller directly onto the motherboard, ridding the controller board altogether. I made a diagram, but I see uploading the DC motherboard is an issue here, so I just put it back on Modretro
 
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