Maker Rob Smith has built a game of Whack-a-Mole with a difference: the “moles” are actually 3.5″ floppy disks, appropriately enough under the control of a Commodore Amiga running AMOS.
“The game is inspired by those whack-a-mole style games, and the hardest part was to get the disks to sometimes pop up, and sometimes pop out completely without having to have stupidly powerful solenoids,” Smith explains of the unusual machine. “After I’d prototyped one of these drives I built five, and then created the electronics to control them using MOSFET and bridge motor drivers, all connected up to several Arduinos.”
For those who grew up after the era of portable magnetic media, floppy disks were introduced as a faster, more convenient, alternative to magnetic tape and before it paper tape and punch cards. Originally living up to their name, being housed in 8″ or later 5.25″ flexible plastic envelopes, later 3.5″ floppy disks firmed up with rigid plastic and a metal shutter that protected the magnetic disc itself. Using one was a tactile affair: slot the disk home in the drive with a satisfying clunk, hear the heads chittering and chugging as they read and write, then eject it with a firm push of the button — and, if the spring’s a little strong, catch it as it flies out of the drive.
It’s this latter part of the process that inspired Smith’s build. The “floppy drives,” installed higgledy-piggledy in the top of a box, are capable of not only ejecting but re-inserting the disks automatically. The drives are under the control of three Arduino UNO-compatible microcontrollers, which are then interfaced to a period-appropriate Commodore Amiga. It’s this microcomputer, which span the late 1980s to 1990s period in home and business computing, which is in charge: the whack-a-disk game itself, dubbed DiskFight, is programmed in AMOS, a variant of BASIC developed specifically for the Amiga and building on the earlier STOS for the rival Atari ST.
“The Arduinos all had their serial ports connected together with a simple ‘only reply if you understand the message’ protocol,” Smith explains. “Finally these were all hooked up to a TTL->RS232 level converter so I could connect it to an Amiga 600. The game also features a perfect 30-second soundtrack by h0ffman.”
More details on the project are available in the videos embedded above and on Hackaday.io.