One thing I’ve always wanted to build is a SEGA or Atari flash cart. My GF has ordered me an EPROM programmer and I so I grabbed some Winabond w27c512 EEPROMs.
While waiting for those to arrive from Hong Kong, I needed to source some donor carts. So went car booting.
I picked up Tennis Ace and Sonic the Hedgehog 2 for the Master System and Mega Games 1 for the Mega Drive for £4.
There’s a brilliant how to on the Little-Scale blog for a write-once 32KB cart, but there’s little info on how to open the security screws. And they’re genuine bastards.
The screws are round topped with small notches on opposing sides.
I have a nice set of security bits, but nothing right. The closest was a flat head bit with slot cut out in the centre. Could those line up and turn the screw? No. The slot was too small.
The solution was to Dremel out the slot (lots of sparks) and tidy with a hobby file.
After a test fit or two, the final bit.
It was not a perfect fit. It chewed the plastic around the screw holes and the screws themselves (as you can see in the photo below). You could do this with any flat head bit of a suitable width.
Mangled. But these aren’t going back in anyway. I had some other, more maintenance-friendly, Phillips headed screws from some dead bit of electronics.
Open and shut case. Here’s the carts with new screws. Simple.