vendredi 1 juin 2012

Game Boy Super Game boy CPU Transplant tutorial


I just finished my CPU transplant between my DMG-01 and a Super Gameboy cartridge.

For Info :With this mod you wont' get more cpu power, or anything similar, it will only change the boot delay, so each time you power-up  the GB, it will boot very fast into the game and you won't get the Nintendo boot sound.

Don't try this if you don't have good soldering skills.

I decided to make a little tutorial, well 2 tutorial in fact. so here is the fast tutorial
1. Desolder your Super Gameboy CPU
2. Desolder your Gameboy CPU (DMG-01)
3 Solder you SGB cpu in place of the GameBoy cpu
That's it.

As I've done some picture of the process, so I did a longer tutorial with pictures.

Super Game BOY CPU transplant Tutorial 

So you want to transplant your super gameboy cpu in your gameboy ? 

Warning: if it’s the first time you desolder or solder SMT components, don't try on your SGB and GB use a old motherboard you don’t need anymore or similar to train you a bit..

This mod need good soldering skills. (normally if you have the skill to do this, you should not need any tutorial )

Tools needed  :
  • Gameboy DMG-01
  • Super Gameboy cartridge.
  • Gameboy game or lsdj (to test afterward)
  • The special tools to open SGB and Gameboy
  • Solder iron with fine tip (and some solder)
  • Flux
  • Ideally a rework station or some chipquick (everything that you want to remove smt component)
  • Time and patience.

Step 1
Before doing everything check if GB and SGB are working fine.
Open your game boy and your super gameboy to make them ready for the transplant.















Step 2 
Desolder the Super gameboy CPU using the rework station or with your preferred method.
(I will not explain how to do it because there is several tutorials on how to desolder SMT component on internet. Just use Google)
 Try to not over heating the CPU during the desoldering process.
Clean the pins of your desoldered SGB cpu with the solder iron



Step 3
Desolder the gameboy CPU using the rework station or with your preferred method.
Do not heat to much the board, CPU or other component. You can lift up a little bit the capacitors near the GB CPU to be sure you don’t touch them with your rework station.
Once removed, check to board to see if everything looks ok. 




 
Step 4
Clean PCB pads after desoldering.
You can use solder wick  to clean or you can put flux on the pads and using the solder iron go across each pad QUICKLY to  melt the solder and clean the pads ,after that clean the flux.

If you use solder wick method, it may be easier to put in place the SGB chip after because all solder will be removed and pads are flat but I don’t like this method because it heat a lot more the PCB than using the solder iron and flux.
Do not apply too much heat because the pads could lift up and it will be very difficult to repair (or impossible).




 
Step 5
 Place the super Game boy CPU precisely to match the pads (check the orientation notch)
Put a little bit of solder on your iron tip.
Hold it in place and using the iron with fine tip, solder one CPU pin in the corner.
Recheck the chip placement and if it’s fine solder one opposite CPU pin
It is easier if you add some flux on the pin you want to solder before soldering.
 After that your CPU should not move anymore


Step 6 
Put more flux on all pins.
Solder all remaining CPU pins, there are several technique to solder them, check video on internet on  how to solder SMT chip. (solder each pin individually or with a little bit of solder on the iron tip move across the pads)
If you make a join between 2 pins, don’t worry you can remove them using some solder wick




Step 7
Inspect attentively all your work, especially  joins between pins or if a pin is not correctly soldered (a magnifier would help). this is a crucial step.




Step 8
Clean the Flux.

Don’t forget this step because depending the flux you use, it can be conductive, and if it’s the case your Game boy will not work or could even destroy your GB.

It happen to me, I didn’t clean the flux  (sparkfun Flux #2331-zx) and the GB didn’t want to boot. After cleaning the flux everything was working fine

If you lifted up the capacitor near the CPU, it is a good time to put them in place again.(before mounting the board in the case)
Solder job is done. :) 



Step 9
Test your Gameboy and enjoy the fast boot (don’t forget to put a game or LSDJ)

If it doesn’t work (nothing appear on the screen and contrast not working) double check your CPU orientation and all soldered pins . (try to resolder all pins and check solder joins)




That's it ... job finished.


Quick video to see the Super Game boy fast boot. :


(sorry for the high compression of the video due to upload on blogger, we don't see anymore the marking on the chips) .

Disclaimer: I am not liable for any damage caused to you, your GameBoy or Super Game Boy due to human error.

Special Thanks to NeX for the idea and the help.


vendredi 25 mai 2012

GameBoy screen LCD fix with rework station (hot air)

So i tested my 2 DMGs and guess what .. lcd probs .. vertical lines problems.
-  on one Gb i got one line not working.
-  on the other a lot of line are not working maybe 15 lines on each side of the screen.
After some google search it seems that it is quite easy to fix. i saw that with a solder iron we can fix that.
As i have a rework station (hot air) i decided to try with my rework station instead of the solder iron.
I tested to fix the most problematic screen first .. and the result are .....taadaa... work like a charm, using rework station to fix this it's like magic.

I would just do a little warning : do not put too much air flow and the most important DO NOT PUT TOO MUCH HEAT. I would say do not exceed 150 C (degrees celsius)

If you set your rework station above 150C it can melt the plastic of the LCD ..

Some pictures:

                        If you look correctly you can see that i've started to melt the bottom of the screen (yes i started this job at approx 200 C)
The white thing on the bottom of the screen  is the electrical table to fix the black rubber (the one you need to remove to fix that)

and taaddaa .. it work fine again .
Sorry i didn't take any picture before the fix, and during the fix, will try to take some for the next one.


Quick picture for the next step, remove this baby and replace it with the super gameboy one.

I just got a good deal on few super game boy, if it is easy to replace i could do some mod service for game boys.




Just got 2 Gameboy (DMG-01)

Just got 2 DMG-01 for a few CHF .. good deal.
I know a few friends who  like and do some chipmusic, so why not add some mod to the gameboy and give it for testing to chipmusic friends.

Mod planned :
- Backlight
- Pro sound
- Super gameboy CPU transplant (great for live act. ultra fast boot and no kling)
- maybe integrate a midi input inside the gameboy
- idea for a distortion inside ..
- some paint job (pimp my DMG)






vendredi 23 mars 2012

Overdrive distortion progress.

Still working on my Overdrive distortion and it is not easy as i was thinking.
Here are the spec i planned for this circuit.

- Soft Clipping (on op amp feedback) and hard clipping (after opamp) selectable
- Hard clipping with Led (to add some blinking stuff)
- not adding too much noize
- true bypass with 4066
- unipolar supply using mc-09 supply
- get a multi purpose distortion PCB (modify diodes, modify gain with trimmers, etc)


You can find a lot of great distortion on the net .. but almost all are guitar distortion, meaning the input signal is not the same, in my case input signal is about 1 to 2 Vpp which i much more that a guitar signal.
This couldn't be a problem but i can't set a high gain on the op amp because the op amp will clip (due to the limited headroom using a 9V single supply) ans the op amp clipping doesn't sounds good.
The good thing about that is the limited gain is also limited noise, but limited gain is limited distortion.
Soft clipping is done by adding diodes (1n4148 for ex.)  in the feedback path of the 1st opamp.

And for the Hard clipping. i planned to use LEDs, so they will blink when distortion happen, but a Typical Vf of a Led is 2V so after the first soft clipping op amp the signal peak is not very high (due to soft clipping) and the Hard clipping effect of the Leds is not very efficient.







You can see here the a soft clippping but peak voltage is 2 volt so the hard clipping after that will not work well..

Adding the Led after for Hard Clipping we get these results  (in RED) :

 as you see, the hard clipping is not very effective. .
So the solution i was thinking is to add a second opamp and do hard clipping after this second op amp.
(also added Led with a higher Vf to stop hard clipping when gain is  low at the second op amp)


 With R4 and R8 will be potentiometers to control the amount of soft and hard clipping ..
see the results here


need to test it in a real situation, because the mc-09 signal is not a perfect sin wave (of course) and adding accent will boost the signal and add clipping on opamp.