I'm still a big fan of the old Atari games I grew up with...from the 2600 VCS, right through the 8-bits to the ST. All along, the joystick was the standard 8-position, 1 button stick.
I've tried gamepads, and just never could get the feel for them, so I was really stoked when I found someone offering a USB adapter to use those old db-9 joysticks on a PC.
More interesting, and the reason I'm posting this here, is finding it works fine with USB Overdrive on the Mac.
The USB adapter is sold by Raphaël Assénat (link to his site), in varying degrees of completion, from programmed chip to finished board. For those gamers of a later generation, the board can be programmed for a variety of other platform joysticks. His site also has a lot of other neat electronics tinkering.
To get the board working with my old sticks, I scavenged a USB cable off a broken Apple USB keyboard, and soldered the 4 wires to the USB end of the board. Note the board is much smaller than it looks on Raphaël's site: it's about 1-inch by 3/4 inches. I had a spare male din-9, which was wired up to the other side of the board. Some of the joystick connections are shared with the board's ISP for reprogramming/updating the Amtel chip's program.
An exposed board rattling around on my desk isn't good, and while one of the suggested options is to place some shrink tubing over the whole board, I wanted something a bit more grand.
I had an old plastic egg in my model-building spare parts drawer, which had once contained a home-made phone-line filter from back in my BBS days.
I had to de-solder the USB connector to thread it through the top of the egg, because I hadn't planned ahead. I used a dremel to cut out a space for the DB-9 connector, and it's held in place with 2 hex nuts screwed into two more hex nuts inside the egg. I considered installing an LED on the USB 5V line, but know from experience I'd eventually find amusing would give way to distracting.
The egg now works nicely with my old Epyx 500xj joystick. On the PC, it requires no drivers, but on the Mac requires USB Overdrive - or whatever equivalents may exist now or in the future.
It took very little time to connect the USB and DB-9 wiring. A couple things to note, though: Since there are different configurations available on Raphaël's site, make sure you're wiring the DB-9 using the correct layout for your joystick's original platform, and with the schematic for the latest firmware or board revision.
There are two jumpers on the board, and depending on joystick platform, these may need to be closed. For the Atari, both are closed, so I found one large blob of solder across all 4 solder points did the trick. If you've overclocked an iMac or G4, you know what fun it is to solder tiny jumpers.
Another note is the site mentions soldering a bridge between PD1 and PD0. On the current board revision, this seems to have already been done.
This is a sweet little board, with just enough soldering and casing to do that I still feel like I've Made Something.