Which was, of course, based off of a standard Panasonic "Hand Held Computer." 😹
http://signalsprocessed.blogspot.com/2012/08/panasonic-hhc-schematics-by-tony-duell.html
Back in those days, of course, ROT13 was enough, but then we upgraded to ROT26...which was a game changer.
@amarand @th3j35t3r LOL or that!
@th3j35t3r
Cite: https://www.cryptomuseum.com/manuf/mils/index.htm