Rope Memory

I just watched a fascinating Documentary on the Discovery channel called ‘moon machines’ I examines the first moon landing and the systems they invented to get there and back. Amongst the invented systems was the guidance computer used to land the LEM on the moon. The computer used only 72k of rope memory. This 72k of memory had to run the OS, guidance program, raise exceptions, and run a watchdog program. This is all pretty astonishing stuff and really shows how far we have come. In case you don’t know what ‘rope memory’ is, go to google images and enter ‘rope memory’. Once the programmers had written their routines on paper, the program was converted to punch cards and the cards were then sent away to another facility where the program was constructed by a bunch of elderly ladies. For this reason rope memory was often called LOL memory ‘Little Old Lady memory’. In these times its hard to imagine writing a program without the need for virtually unlimited RAM, a visual display, an emulator or a keyboard. If ever the term ‘we stand on the shoulders of giants’ were true, in modern computing, it is fact.

Took a history of computing course from this fellow
He had all kinds of cool artifacts like a 4k core memory unit that was probably 4 feet long and a couple feet tall & wide
Huge heavy thing for 4K
But to see all those hand wired ferrite cores on there and now look at a tiny chip that has 4Gb on it (or more) is amazing how far we have come

*got an A in the course and “Mike” suggested we co-publish my research paper on the ABC computer
Never did

[quote=196976:@Norman Palardy]Took a history of computing course from this fellow
He had all kinds of cool artifacts like a 4k core memory unit that was probably 4 feet long and a couple feet tall & wide
Huge heavy thing for 4K
But to see all those hand wired ferrite cores on there and now look at a tiny chip that has 4Gb on it (or more) is amazing how far we have come

*got an A in the course and “Mike” suggested we co-publish my research paper on the ABC computer
Never did[/quote]

Some months ago we had a little disagreement with each other on Kerosene (RP1) and rocketry, during the course of our debate, I thought “this Norman fellow knows more about rocketry than he is letting on”. Looks like I was right.

Question for Norman. Could the rope memory be classed as RAM or sequential access memory? I am not sure how you randomly access a bunch of ferrite rings.

The picture of the ABC computer has raised doubts in my mind. No keyboard, no mouse, no display. What were they thinking??

ease of use?

Maybe Steve Jobs was involved in the design (minimalist philosophy)

Lovely looking machine that ABC. You could do random-number generation by taking a card deck, shuffling it, feeding it in, and reading base2-out.

The machine looks portable too - on wheels.

:wink:

Yeah, sure is a regular mac book air clone.

Operationally it was random access
The exact details I dont recall.
That course and learning about the memory itself was 30 years ago this year :stuck_out_tongue: