My first Build - portable Megadrive

If it's a momentary switch, then bridging the pins will not make it always-on. You'll need to figure out a different way to accomplish that.
 
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Main amp on back of speaker. Red and black cable going left is the other speaker. I've had to attach a new wire to the audio in (it's the thicker red one) cause the other one fell off and I can't figure out where it went for now. ^_^;

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The control board and headphone jack and power in. the ribbon cable attaches it to the main board, I'll use the Battery + - for the power, so the three ones for the jack can be removed. the cables on the far right go to the Ipod connector. I'm pretty sure I can safety remove them as connecting to the amp board is fine and allows the controls to work.

I'm not sure what kinda switch that is.. my knowledge of switch's is.. dated ^_^; If I can't bridge it.. I wonder if I can just connect it to the megadrive's power switch.

Oh, pretty sure it's a Tactile Switch. no.. i'm probably completely wrong on that..
 
I was right about the switch I think cause though I can't see it lower for being pressed down, when it's down, and I connect up a power source, it automatically turns on. so I guess it's a standard 'press the button to complete the circuit' switch which I more know about ^_^

tried powering it directly from the Megadrive's 5v regulator and that works fine so I can solder that connection. and audio tests out fine.

so.. next stage is to work out some more details for putting together and see about editing parts like moving the cart slot and buttons..

Had a minor set back.. my plans for the gamepad turned out to be completely (well.. half) different.. my controller has only the buttons on the front of the board, the 4 buttons for the direction pad are UNDER the board, controlled like a joystick. Minor thing, I can build it to use that without much trouble.

I think I can remove half the wires on that speaker setup. basically, the power port connectors aren't being used, cause I'm using the two for the battery. the connectors to the Ipod connector apart from the three for audio are pointless, so they can be removed.
 
right.. current status:

Everything is hooked up for power. Megadrive seams happy to boot up and run (though I'm wondering a bit if there is a minor cpu issue.. I need to check on this but it's probably a bit of dirt ^_^

anyway.. screen works fine. audio is the problem.. it seams I might have.. somehow, knocked out the copper circuit strip from the connector port when I removed the port. So I'm trying to trace it a bit to see where it connects so I can see about just a direct connection.

pictures soon but sooo many things going on.
 
naw.. doesn't seam possible in this case.. too much going around corners (well.. pretty much) would need replacing all the way up to the connection port.

Looks like it just goes from the connector to one of them really small chip resistors, which goes into a compactor before going to the audio chip
 
Sorry for delay ^_^ (sure I had notify me turned on and I've been a little busy of late).

so far.. not great. I'm going to have check again both the megadrive audio and the speaker board.. the speakers turn on but just no sound so I think a wire is a bit iffy.. which is why I need to fully test it and the megadrive to make sure it's not that side of the sound which has gone..

other then that, it's working perfectly. huming and harring over if I should unsolider and move the cartslot to the place I want it OR should I buy a cheap old action replay or game genie to make a extender..
 
Had a bit of time today between things, for some reason, I must have broken a connection and not patched it right on that speaker set ¬_¬ very annoying as that's pretty much wasted.. might try to fix it up for something else later..

in the mean time, got an old PC speaker, which has a much nicer and stronger amp board, and it works. Need to do a bit more work and attach it right etc, but it works. So I got sound ^_^ yay!

not 100% sure how strong the amp is.. though it should be pretty good, cause it sounded a bit low, but then, it wasn't connected up right or anything to test. so that's minor. Also need to work out the placement for the headphone jack. I'm pretty sure I did ask and get an answer but the headphone socket should be located on route between the amp board and the speakers I think.
 
Audio works. new amp works fine, good volume level now connected correctly to. requires 12 volts though, so I added it to the split from the battery. that Now powers the Screen, the Megadrive and the Audio. seams happy with it though I'm now a bit less sure of the Battery life. Should be good BUT not sure what the full life is. will have to test.

Tested it and fully runs on the battery without problem. Need to connect up left audio channel however, but that is minor.

Still need to add Headphone socket. By the looks of how the circuit is, it would be best to add the socket between the Megadrive audio outs and the Amps audio in. this will, however, mean I cannot change the volume of the headphones unless I use a headphone with a built in control. most likely a minor thing though. I cannot see much of a way to add it otherwise. If I added it to the Right or left speakers, it would still allow that speaker to work, so that doesn't seam valid.. partly wishing I had picked a speaker that had a headphone jack in it but no real need and this is perfect.

Photos soon (Hopefully tonight) of my.. messy connections. Case Design for a prototype case underway at the moment. It'll be wood construction but I'm looking to replace it with Plastic at some point. Still need to relocate Cartridge Slot, Power button for Megadrive and Reset button for Megadrive.

EDIT: Nevermind about the headphone socket.. I'm an idiot and I remember where to put it now

EDIT 2: seams I won't get too much time for the photos till the weekend..
 
not really much to look at but..

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I've tried two different Headphone Sockets I got, connecting them to a PCB board and attaching the wires but I don't seam to have much luck with them so far.. so I'm not sure if i'm going to just order some new ones or what..

There is one I got but that is one way only.. the pins are.. either inputs or outs but not both..
 
okay, Got a headphone socket with a 6 pin switch (the old I did have the switch was broken and I wasn't sure I needed it ^_^; headphone sockets aren't my field at all)

not 100% sure on the wiring for it.. hopefully find out tomorrow (I understand the 5 pins on the headphone socket itself I think.. Ground, Audio left in, Audio left out, Audio right in, Audio right out.. but with the 6 pin switch added to the back, I'm getting a bit confused)
 
now a little confused..

hocked up headphone jack right side so, right in, right out and ground. when I plug in headphones, it works perfectly.. Apart from.. the Speakers.. sound only comes out of the speakers WHEN the headphones plugged in.. else nothing comes from the speaker.. that's.. a little weird to me..

EDIT: Slight improvement.. speaker is on all the time..

EDIT: Fixed!. with help of a spare one I took apart, I was able to find that that right audio in and the right audio out pins ,internal, had moved a bit (probably one pin came out too far and was pushed back wrongly) so that when the jack was inserted, the connection couldn't brake. I shifted them about carefully and now it's fine.
 
Power and Reset Buttons Extended. but i'm debating if i'll be able to move the cart slot.. them 60 pins (or is it 64?) in a small smart would be a real bugger...

I can easily get the female connector from a Game Genie or Action reply but.. the male? from that source might not be the best..

any advice?

also, I need to cut the board.. i'm pretty sure it's 100% safe to just cut the extension board.. hang on.. is that the same number of pins?

EDIT: Of course not.. sorry, eyes a bit blurry when counting ^_^

Got an old game genie coming out. also forgot to attach the controller. seams to have had a problem with the wire used.. it's . weird stuff which has small fine bits of wire and mostly some form of thread. I got it all connected correctly but it doesn't recognise (at first, it did a couple of buttons but not well or correctly.. I think cause there was a minor crossed connection).

I got some wire coming so I'll just rewire the whole thing.
 
rewired the controller.. wire fine but.. buttons don't want to work right..

a standard European megadrive controller. Model number:1650

I worked out, as you look at the controller, the pins
0 1 2 3 4
5 6 7 8

0=green
1=yellow
2=orange
3=red
4=brown

5=blue
6=grey
7=black
8=white

where

0 = Up
1 = Down
2 = Left / Ground
3 = Right / Ground
4 = +5v DC

5 = Button C / Start
6 = Ground
7 = Select
8 = Button B / Button A

but that doesn't seam right.. the A button seams to function as the C button and start (at the same time which is.. odd). so I might have them the wrong way around... which should be easy to fix.. (might be much easier right now, to just change the connections on the board side more then the megadrive.. oh well..
 
okay, the controller is rewired and seam to be fine.. might need to check a couple of the wires.. but for some reason, while it worked this morning, the screen doesn't want to power up either with the battery or using an external adapter I used to test with.. the only wires that are solder into place are the video ones, not the power, and that doesn't seam to be anything wrong with them..

so two things remind.. the board is blown.. somehow.. not sign of that at all.. OR the wires for the power needs replacing.. bugger..

EDIT:
Tested the wires.. they are fine.. how the Heck the board blew is beyond me.. still no sign of damage or blown parts or anything.
 
got new screen.. installed.

Megadrive seams to be on the blink.. doesn't output Video or Audio signals. when I have a gamegenie pluged in, it does allow it's onboard light to turn on, so I guess power is supplied to the cart, as it is to the Megadrive.. trying to figure it out but.. too many things going on and getting a little clueless ^_^;

can't see any crossed wires.. unplugging the screen so it's not connected doesn't seam to change anything either.

EDIT: Wondering if it might be to do with the power button as I think I need to redo the wires (one seams to have come out).. there are 2 pins on one side, and 3 on the other.. any one got a guide to which does what? I mean, i'm guessing the flow of power via it means one probably turns it on for the processor, one for the cartslot, maybe one for the controller?
 
checked the power, redid it, no change..

something is stopping it booting up.. not quite sure what..
It does power up, the cartridge slot gets power too, and yet nothing is being outputting (not even a black screen) so something is up.. might have to re-check he power to see if the ground is all connected right but I think it is..
 
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