After a bit of fiddling around and faffing (and eventually giving up on the OSX side of things) I managed to get a 35-year old Atari 800XL talking to a modern-day Windows computer. Not only talking, but even reading and writing files back and forth.

The secret to this black magic is twofold. Firstly, you need a bit of kit called an SIO2PC module, which converts the signal from the Atari computer's SIO hardware — used for communicating with peripherals such as disk drives and cassette decks — into something which can be interpreted by modern systems, since SIO was a proprietary format and cable type. The SIO2PC module I had was serial-based, so I then had to run it into a modern computer using an RS232 to USB converter cable, since many computers these days don't come with serial COM ports as standard. The cable effectively sets up a "virtual" COM port via USB, tricking the serial device into thinking it's plugged into an actual serial port on the PC.

Once you've got that bit sorted, you need some software. There are three pieces of software I've experimented with today. Firstly, SIO2OSX just didn't work at all. I don't know if I didn't set it up correctly or if the Mac simply didn't have the appropriate drivers to set up the virtual serial port — though said virtual port certainly appeared for selection — but eventually I gave up and switched to my laptop PC, which has been gathering dust for a little while now.

Second up was Atari Peripheral Emulator, or APE for short. This Windows-based tool emulates a stack of Atari disk drives, printers and modems, allowing you to mount disk images and (theoretically, anyway) boot from them. I had trouble getting this part of the program to function correctly, but what did work was a separate application distributed as part of the APE package called ProSystem. This is a much simpler tool that allows you to either "rip" Atari disks to .ATR disk image files, or take an .ATR disk image and write it to a physical 5.25" disk to use in the Atari disk drive. While APE failed to do what it was supposed to, ProSystem had no problems whatsoever, reading from and writing to my ageing Atari 1050 disk drive with no problems whatsoever.

The final tool I tried was AspeQt, which is still in active development. AspeQt is pretty much an open-source tool that does most of the things APE does — APE is shareware — but I found it to work much more reliably than APE for simply mounting disk images and using the PC as a "virtual disk drive" for the Atari. AspeQt also has an excellent feature that I was specifically looking for: the ability to extract individual files from .ATR disk images and save them as standalone files on the PC filesystem. It even automatically converts from ATASCII — Atari's proprietary take on the now-standard ASCII character set — to standard ASCII, meaning that files such as AtariWriter documents can be easily transferred to PC for dumping into other applications with all the requisite line breaks and suchlike intact rather than being replaced with special characters.

My current Atari setup, then, is a bit of a kludgey mess, using ProSystem to rip and write complete disk images and AspeQt to mount and use individual files on a disk or image — ideally APE would act as an integrated solution for all of this — but it works, by God. And, boy, was it exciting to hear the 1050 snark into life when I clicked a button on my Windows PC. Just to prove it really worked, I downloaded a disk image for the AtariAge forums' current High Score Club games and wrote it to a blank disk. A few minutes later, I had a bootable floppy disk that you'd never know I'd downloaded from the Internet running on original Atari hardware. Black magic, I tell ye.

Getting all this working opens up all manner of exciting possibilities, and I'm sure I'll be exploring them more in the coming weeks.