I finally got finished with my FB2 Rev B menu button (aka soft reset) mod. This mod allows you to go back to the game selection menu without toggling the power button. This mod is completely independent of the cartridge mod. It can be added in addition to the cartridge mod, or as a standalone mod without the cartridge.
I've been playing with my FB2 both before and after this mod, and I must say the overall experience is much nicer with the mod. I really love being able to quickly go back and select a different game. Not that it's difficult to cycle the power button, but this just seems more polished to me.
OK, so let's get to work!
You will need the following items:
A momentary contact SPST pushbutton switch
Some small guage wire (26 - 30 AWG will work best)
A soldering iron and some solder
Some hand tools like a screwdriver, file, drill and drill bits
You will need to take the FB2 apart by removing 5 screws from the bottom. One screw is in the center under the white label. You will also have to break the warranty seal to open the unit. Once you have it open, remove the main circuit board from the top cover by taking out all the small screws. You will also have to remove the screws from the two smaller circuit boards that hold the power and difficulty switches. You will be soldering two wires to the main circuit board on the bottom (green) side. Once you have it apart, you can start by preparing the switch and mounting it in the case.
I had a switch that was leftover from another project. I think I ordered it from MCM electronics some time ago. This is what it looked like in the package:
This is the switch taken out of the package:
Next you will need to solder two wires to the switch terminals. You can use the same color wire for both since polarity doesn't matter here.
I used some heat shrink tubing to cover the solder connections and add some strain relief. This step is optional.
Next, you will need to make a hole to mount the switch. I chose the left front edge of the top cover. I used a smaller drill bit, then finished the hole with a hand file.
Here is a close up of the hole:
Here is the switch mounted in the top cover:
And a look from the underside of the top cover with the switch in place:
I had to file a small relief area in the bottom cover so the switch would fit when it was all put together:
Next you need to find the correct points on the circuit board to solder the two wires to. Look for a zero ohm jumper resistor marked J19 to the left of U2 (the ROM chip that's under the big black blob near the top edge of the board.) You can solder the first wire to either side of J19 as both sides are connected to ground. The second wire from the switch will connect to a round pad just above C10. Take a look at the two photos below. The second one is a close up of the board. The two points you need to solder to are marked in red in both images.
Here is what mine looked like after I soldered both wires in the correct place. It would be a good idea to glue or tape these wires down to the board for strain relief. You can use hot melt glue or electrical tape. Just be careful of the placement so the wires don't interfere with any switches or buttons when you put it back together.
Now put everything back together and test it out. The FB2 should power-up normally and show the game select menu on the screen. Once you select a game, you can now go back to the menu by pressing the new button you just installed!
Here is my unit fully assembled with the new menu button.
I plan to add some lettering above the button that says "MENU" at some point. But it's functional for now so I'm just going to play some games instead and worry about that later.
I would love to hear any constructive feedback or suggestions.