Sometime in the early 2000s I acquired a Kaypro 2/84 computer (side note: the picture in the wikipedia article with the mis-matched floppy drives is actually my Kaypro!), and I’ve been meaning to do something ‘interesting’ with it ever since. It’s a nice Z80-based ‘luggable’ computer running the CP/M operating system. General stats:
Z80 Processor @4 MHz
64KB of RAM
Upgraded to use the ‘Advent TurboROM’
Upgraded to dual DS/DD 5.25″ Floppy drives (360KB/disk)
9″ green CRT supporting 80 columns x 25 rows (or 160×100 pixels in ‘graphics mode’!)
Two RS-232 serial ports supporting speeds up to 19.2Kbps (one of which is tricked out with a sweet Wifi232 module, the other unused)
One Parallel Port (currently unused)
Unpopulated internal areas to support a real-time clock, and a 300 baud modem!
The TurboROM also adds support for the following (if you can find them, and/or figure out how to wire them in):
Up to 2 RAM Disks of 256KB, 512KB or 1MB each
Support for up to 4 floppy disk drives (180KB, 360KB or 720KB)
Support for up to 2 Hard Drives of up to 56MB each
All in all it’s a pretty neat machine, and it’s an interesting example of the early computer world before Apple and IBM-compatible machines killed off all the competition. One of the nice things about a Z80 CP/M machine like this is that there’s actually a semi-viable software ecosystem lovingly archived and available fore free on the internet. You can find lots of ‘productivity’ software (spreadsheets, text editors, etc.), terminal programs, text-based adventure games like Zork and even development software like compilers. My recent forays (1, 2) back into game development got me thinking – how hard would it be to write a ‘graphical’ game for my Kaypro? I stumbled across one or two drawing programs for the Kaypro, but almost nothing else that actually took advantage of its limited graphics capabilities.
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.