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Re: Is this site interested in portable handheld DreamCasts?

Posted: Mon Nov 02, 2009 11:23 am
by bacteria
Needed to make the daughter board connecting the DC to the controller slim, so removed the ports, flattened the battery and wired it to the back of the board.

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I could have reduced the board by about half size if needed to, will leave as is for the moment.

Also secured the perspex top to the main case by a couple of screws into the plastic posts - keeps everything in place.


Here is the fruit of just over 3 months work (project was started around 25 July originally, as I recall).

Left: DreamCast - drive unit dismantled, wired to use a TI card and 7805 to work off 7.4v; rewired the connection from the DC to the drive board, reset it, reduced parts of the drive surround, trimmed the DC board a little, added heatsinks and fan for the processors, relocated many of the capacitors, reduced the daughter controller input board.

Middle bottom: made a case out of tupperware and perspex, painted it, added screen, buttons (modded controller for button holder, also modded the buttons), speakers, d-pad (with own made assembly), rumble pack, VMU unit with see-through window (VMU was halved and re-wired), using different joystick, perspex shelf to hold DC system (secured in place by screws), shifted d-pad/screen controls.

Middle top: made a case out of tupperware and perspex and also PSone case top (modded), three sets of 7.4v 2amp Li-ion batteries, switches, shoulder buttons, exhaust fan, another fan to be added to drag in around case; plastic strip to secure case halves together.

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Everything still works (phew), next job will be to use RGB instead of composite, and rig up the audio. I have never heard a DC boot up yet, just seen the images. Shoulder buttons work fine too, tested on Quake 3 briefly - interesting, when you fire a weapon, the rumble kicks in too - the rumble in my case is quite strong, although it is only one motor - about the same kick as holding the controller with rumble pack installed.

Case feels nice to hold, all controls and buttons are "just in the right place", weight ok, although it will be heavier when the DC guts are added!

Re: Is this site interested in portable handheld DreamCasts?

Posted: Mon Nov 02, 2009 2:38 pm
by Dihnekis
That is so cool.

Re: Is this site interested in portable handheld DreamCasts?

Posted: Tue Nov 03, 2009 12:47 pm
by bacteria
Got audio rigged up, wired the screen to the main power source, wired up RGB - just got audio - then realised, according to this site pin 7 needed to be wired to grounding to enable RGB mode instead of composite or S-video. Crap, very fiddly work to get the iron in there, solder a 1mm wire in a 3mm gap (1mm each side) and not make a short with a blob of solder joining pins together. Easy solution would be to wire on the reverse of the board, however that isn't going to happen, can't turn the system over or everything will fall out or dislodge...noticed one more thing, one of the audio wires was loose, only got one speaker working...looked at the wire, moved it, sure it was loose. Rats - and it was against the drive unit and board, drat and double drat (to quote Dasterly and Mutley), took over an hour to solder these two wires back (and not touch a neighbouring pin carrying voltage that would have fried my screen), but before I did, hisssss - aaarrrgghhh - frazzled the drive ribbon by touching it with the iron! Anyway, had a spare ribbon cable, changed it; tested system, get RGB and proper stereo audio now! *phew*.

So, works fortunately, and in RGB mode - I think the colours are a little bright, on the guide above it talked about using a 220uf capacitor on each of the RGB lines, so will give that a go if I need to. More experimenting to do.

I wired directly to the pins, this would have been easier - someone asked for a pinout, so worked it out from my spare board:

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Re: Is this site interested in portable handheld DreamCasts?

Posted: Wed Nov 04, 2009 2:37 am
by Dr. Pariolo
smith wrote:bacteria, do you plan on making more portable dreamcasts in the future?
That means he wants you to make one for him.

Re: Is this site interested in portable handheld DreamCasts?

Posted: Wed Nov 04, 2009 3:52 am
by bacteria
Sorry, not making them for sale, just a one-off; anyway, if I were to sell one, given it takes a mountain of time to make one, even at a conservative $25/$30 an hour, that would mean about $7000 :o

:lol:

Better I show people how to make their own, as I have been doing.... :lol:

Re: Is this site interested in portable handheld DreamCasts?

Posted: Wed Nov 04, 2009 8:54 am
by bacteria
Thought I would wire up my only spare DC (unmodded) to a/v cable, did that without removing all the guts, just hacked off a little of the plug surround on the outside of the case, and then very carefully soldered the 4 needed wires, and connected to my main television - worked fine. Played a little Cosmic Smash, one of only two CDR's that my PAL DreamCast's seem to want to play (all other discs are coasters); and a little Sega Rally 2 - wasn't bothered about that game, still, only cost me £1, so no bother. Then thought I would play Shenmue to see if I liked it - disc kept saying "wait while checking disc" (or similar message), then got a beep and the game started to load, after a couple of seconds, back to the DC menu. Rats, obviously the system was not good, laser probably worn out, so took off the top of the console and turned the small dial on the back of the laser 1/4 turn as I had read on many sites before, as that "recalibrates" the laser - this time, when the DC was turned on, most of the time went straight to the swirl and "DreamCast" word on the screen, then just the DC menu - the games working before ok no didn't. So much for the adjustment of the laser! Killed the system!

That means I don't have a spare DC anymore, will have to buy one when I see one at a car boot sale again in the next weeks. The weak point of the DC seems to be the laser mechanism, as I have read in many articles.

According to this site and its two articles: *1* and *2* a 220uf capacitor and 75r resistor is needed on each of the RGB lines to correct the RGB signals; I read this on other articles on other consoles too, so no surprise. Desoldered some capacitors from old boards I have lying about, the resistors are new as have a pack of them; wired up:

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This is the stage where things get interesting, and I must admit, i'm rather nervous - system tested for final time, all works great, nice picture, RGB working, nice audio, all great. Next stage is to get the console inside the casing and shorten and re-attach wires as needed, and also rig the system up to the batteries; ie this is the stage where final assembly takes place, back of drive unit screwed into the case backing, and final project stage. Have to be very careful not to kill things now! :roll:

Re: Is this site interested in portable handheld DreamCasts?

Posted: Wed Nov 04, 2009 10:24 am
by bacteria
Last project update for today, will have the wiring to do tomorrow. Cut off the power lines so can get system into case.

Hot glued a wire to two ends of the board to act as a crane to lift and lower the board onto the case and maneuver it into place.

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It is in - to say there isn't a single millimeter to play with is not an understatement here, as you see, rumble motor moves freely, about 1mm from the board.

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I will be most annoyed if anything goes wrong now with it!!

Got to check the drive unit is in exactly the right place, can move it about a few millimeters if need to, a dozen or so wires to reconnect, fix the DC fan, install a 4th fan (not going to risk extending the DC fan's wires - heard before it may cause the DC not to boot), fans take next to no power, so may as well just slap another one in there - to move air around case and also airflow over the heatsinked 7805.

Should have all done tomorrow, assuming no issues with the doctor - been having a constant minor gripe on my right side of my chest for weeks, barely anything but consistent - might be appendix, might be something else or nothing, seeing doctor in under an hour "to have a chat". Assuming all well, and on project tomorrow, and things working still and not frying on the project (so many things close to each other in the case) may have it done...

Re: Is this site interested in portable handheld DreamCasts?

Posted: Thu Nov 05, 2009 12:49 pm
by bacteria
Spent a while removing the power supplies (the 7805, TI card, etc) and rewiring them, also tidying up the wiring somewhat so the case will (should) shut, installing extra fan, etc.

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I have made a few more mini videos for "part 2" of my WIP guide, however not uploaded them yet - intend to do that in the next days and probably compress the guide into just one 10 minute video for ease of accessibility - if not, into two parts.

So, here is the video just made - hope you enjoy it!


YouTube video


In the next days, when I get time, I will try and get the case gingerly closed and see if all is ok!

Re: Is this site interested in portable handheld DreamCasts?

Posted: Thu Nov 05, 2009 1:50 pm
by Dr. Pariolo
congrats dude! :D

Re: Is this site interested in portable handheld DreamCasts?

Posted: Thu Nov 05, 2009 3:18 pm
by Bob Dobbs
Got my eye on it.