GBexx: fit it without modifying a GameBoy
In the other file, I explained how to fit the GBexx card to a Gameboy computer. It relied heavily on screwdrivers and hobbycutters... Kind of barbaric, if you have fond memories of your game console. But there's also a slightly more sophisticated way involving much less tinkering inside the GB.
Please make sure you also read the other GBexx fitting related webpage.
Take the GBexx card and change it
On the right, you the GBexx card with two 'trenches' carved out. The location of the trenches is just outside the power/ground connectors. The width is not very important, but 'as narrow as possible' is a good guideline. Below are close up pictures of the trenches near the GROUND signal (left) and the +5V signal (on the right).
As you can see, I made a design error while pooring the copper for the power/ground planes: the connections are on the sides of the contact fingers. So when making the trenches just besides the contact fingers, both the power and ground fingers are separated from the rest of the circuit.
This is quite a problem. We would need at least the GROUND signal. And the +5 Volt signal would come in handy too. So we must fix this problem.
The fixes you can see in these three pictures. I soldered small wire bridges over the accidentally isolated signal lines. Make sure the wire bridges stay well clear of the trenches, otherwise you did all your filing and milling in vain.
In order to be able to solder the bridges, scrape away the green solder resist laquer with a sharp hobby knife and apply some flux paste. Then quickly apply some solder (preferably Sn60Pb38Cu2, the old fashioned kind containing lead) since the copper will oxidize quite rapidly.
GBexx: populating the board
Now you just need to populate the board, like you did before (in the 'Fitting GBexx' section).
You can see full sized pictures (3072 x 2304 pixels) if you go to the site where I parked all (raw) images:
The GBexx board with this trench modificatioon, plus the 0.8 mm thickener, mounted underneath the contact fingers, allowed the board to be mounted in ANY GameBoy Color or GameBoy Advance I could lay my hands upon.
Page created 9 december 2006,