Replicating 1960s-era computer hardware can be a daunting task. Components can be hard to find, schematics thin on the ground, and software near-unobtainable. Of course, not every computer from the decade consisted of expensive high-end electronics – CARDIAC was built out of common cardboard, and making your own is a cinch!
CARDIAC stood for Cardboard Illustrative Aid To Computation. Consisting of a series of sliding cardboard parts, it acted as a basic guide to the principles of computation. Through the use of a pencil and the associated guidebook, students could run simple programs to learn how to program computers at the barebones level.
Finding the paper-based computational learning tool highly valuable in their youth, [megardi] wanted to bring it back for a new audience. Thankfully, there are plenty of resources on the web that made it easy to whip up art files to reprint the device. [megardi] then also wrote up the instructions on how to accurately reproduce a CARDIAC, with helpful tips on how to best put it together. For a quick test, any old paper will do, while using 110 g cardstock and a laminator makes a sturdier build that can be used with dry-erase markers.
CARDIAC remains an excellent tool for teaching the basics of Von Neumann architecture computing. We’ve discussed similar teaching tools before, too – from the days when “real” computers were too expensive to let students anywhere near them. How times change!
I still have my original CARDIAC in a box somewhere. There is a simulator on line at
https://www.cs.drexel.edu/~bls96/museum/cardsim.html
I was inspired to add an animated block diagram to that.
https://jamesnewton.github.io/cardiac/index.html
Also CARDIAC gets a chapter in O’Reilly’s 2016 FPGA book – Make:FGPA – They explore a Verilog version of the CARDIAC call VTACH
DrDobbs 2013 Article – https://www.drdobbs.com/embedded-systems/cardiac-to-fpga/240155599 (By Hackaday’s Al Williams?)
Make:FPGA – http://shop.oreilly.com/product/0636920031536.do
Instead of a HALT instruction, does it have an ARREST instruction?
On an ATTACK instruction? lol!!
The Halt instruction is HCF for halt and catch fire.
Don’t forget I put Cardiac on an FPGA: https://www.drdobbs.com/embedded-systems/cardiac-to-fpga/240155599
See also:
https://opencores.org/projects/vtach
https://www.drdobbs.com/embedded-systems/the-heart-of-a-cpu/240153772
https://www.drdobbs.com/embedded-systems/expanding-vtach/240155198
https://www.drdobbs.com/embedded-systems/paper-to-fpga/240155922
I see you too were the recipient of “human-in-the-loop” moderation!
https://hackaday.com/2014/10/14/a-clever-cardboard-computer/