Baylex - 1st Gameboy Zero - No AIO

[Baylex]

Hi everyone, I present to you my first project. Obviously a regular gameboy zero, but without any fancy things like AIO's. I am trying to do things my own way and figure out myself where to put everything without following any specific tutorial.
For materials I am using a slightly different approach than a few people here on the forum. Most people use the Powerboost from adafruit for example, but to be honest I think they are very expensive, so I decided to use a battery charger and a step up converter. Most things have been bought from China and I am trying to build this as cheap as possible.
I haven't done much so far, but I got everything that I need apart from the leonardo pro micro which got lost so I had to order another one.

SpoilerShow

List of parts:
Amplifier x 2 £2
http://www.ebay.co.uk/itm/272422272479

USB Female £1
http://www.ebay.co.uk/itm/282544199274

Case DMG £3.88
http://www.ebay.co.uk/itm/282524987431

Micro usb ext £1.36
http://www.ebay.co.uk/itm/152382136143

PCB board £1
http://www.ebay.co.uk/itm/122532548647

Speaker £1
http://www.ebay.co.uk/itm/302133541123

Headphone jack £1
http://www.ebay.co.uk/itm/322182792944
HUB £2.15
http://www.ebay.co.uk/itm/390567004512

Volume pot £1.25
http://www.ebay.co.uk/itm/201977926331

Leonardo pro micro £1.86 http://www.ebay.co.uk/itm/152632830116

3.5" TFT screen £10.79
http://www.ebay.co.uk/itm/191796614485

Step up converter and the charger I had bought these for quite a while now for a different project I have done. They costed me like £3 each for 5 of them.
http://www.ebay.co.uk/itm/222129973093
http://www.ebay.co.uk/itm/263169001914

The screen I got from China came with a broken ribbon cable, so had to order another one from the UK. The one I got was this massive board which a lot of people are getting now. It doesnt fit inside the gameboy case without some trimming, the good thing is that it works straight with 5v and after trimming it down it gets very compact.

(Pic by brigghius)
I will post a pic of my screen trimmed after.

Here are some pics of my pcb for the buttons and the extra x and y button holes done in the case.

SpoilerShow

Board cutted used a small part of the pcb to do my low pass filter for my pwm circuit. Still trying to find out if I really should use it or no. Havent gotten to the sound part of the project.



Pcb with holes in it ready to fit the gameboy.



Colors don't really match because of the flash.



Here is a photo of screen and pi running out of 5v without modifications.

Next step will be to desolder the female usb ports from the HUB, start working on the sound and figure out more or less where everything goes.

Let me know what you guys think!

[shesaysidontlisten]

Did you gut a SNES controller for the buttons? I went to buy a used one today and didn't realize they are about $15-17!

Does the Leonardo pro take the place of a Teensy?

Looking forward to your build!

[Baylex]

Yeah I got a SNES controller for the extra buttons. That was my first project actually, putting a rapsberry pi zero into a snes controller, hence why I already had the step up converter and the charger. I bought a controller on ebay from the uk for like £3, dirt cheap.

Yes leonardo pro would replace the Teensy which are very expensive. Make sure youre getting the one with the ATMega32U4 chipset at 5v 16mhz, apparently they're easier to program.

[YaYa]

Very interesting approach ! Good luck with your build

[Baylex]

I have done a bit of work on my project. Not much in terms of working on the actual gameboy case, but did workout how the sound is going to look like.

SpoilerShow

Now, the reason why I did everything on the breadboard was because I wanted to try different approaches. I think I got the best results with everything in this order:
Pwm>low-pass filter>potentiometer>headphone jack>amplifier>speaker

I still get a hissing sound when volume is all the way up and I can't seem to get rid of it. The second problem I encountered is if I have the headphones plugged in and the volume all the way up, the speaker outputs some sound as well. The sound is very quiet but it is noticeable and defies the purpose of having headphones.
I will still look into this and share any knowledge that I may find.
Apart from that the sound is not that bad. Headphone quality is very good, this actually surprised me a lot.

[shesaysidontlisten]

Watching this one. I haven't diagrammed out how all my audio will work yet. Let's see what the resident experts have to say.

[YaYa]

I suppose your headphone jack is a switch type ? When you plug the headphone, the switch cuts the sound to the speakers ? Or , i mean, should cut ?

[Baylex]

Yes it should cut, and it does more or less. Lets say the volume on speaker is at 100% , when i plug in the headphones the sound goes to them and is 100% good, crystal clear. BUT, there is still like 5% volume left on the speaker. I think I have everything wired up correctly, but I will post a diagram of my wiring today so everyone can see what I'm doing.

Edit:
Here is the diagram, just beaware that all my grounds are connected to a breakout board.

[YaYa]

did you try another jack switch ? it sounds like a problem within the jack instead of other problem... or maybe if you can see the pins in the jack try to bend the one making the contact off while the headphone is plugged to be sure it won't leave a small contact and thus some sound flowing to the speakers ? i hope i'm clear lol