On: What Did Ada Lovelace’s Program Actually Do?

[plesner]

Babbage's notes describe what we would call branch-if-zero and branch-if-negative instructions which you could use to implement repetition. Control flow was the least well developed part of the instruction set though, presumably because it would be trivial to implement compared to the arithmetic operations so it could wait.

If you're interested in that kind of thing I wrote a description of the entire instruction set a while back: http://h14s.p5r.org/2012/11/punched-cards.html.

[NeedMoreTea → plesner]

Having just spent the last half hour on your blog I'm even more impressed by what the pair of them achieved.

Thanks for the in-depth, and wonderfully clear write-up.