deramp5113
2 HN recommenders · recommended in 3 months, 2021–2024
9:00 · 144K views · Oct 5, 2013
A demonstration of loading Altair 4K BASIC on an Altair 8800 clone, using a front-panel bootloader and an ASR-33 Teletype. It shows the full sequence of entering boot code, loading BASIC and running a program.
Cited as a great demo of how early microcomputers were actually booted and operated.
3 comments from Hacker News
I like the very early microcomputers where the storage is paper tape punch / reader. Your ASR-33 basically types in your program, or punches it on tape when you "list". You can see some of these on "deramp"'s videos (he is selling Altair clones, but even so the videos are great demos). this video The next upgrade to this is something like the AC-30 for SWTPC. It does exactly the same thing, except uses cassette tape. [LINK] Then came disk drives, but no DOS. Instead they use disk the same way you used the cassette: [LINK] It was up to you to remember which track your file was on.. Next step: file names, but no automatic space management: [LINK] You write files sequentially to the disk, and you can only write to the end. When you delete there are holes. You can run a defrag program to recover the space. This stuff was all just before my time, but there were vestiges of it in later operating systems in the early 80s.
There's a nice video here of a complete BASIC boot sequence - entering boot code, loading BASIC, then loading a BASIC program. this video As far as any program was concerned the TTY was just a serial port, and it couldn't tell the whether data coming in was from keyboard or paper tape reader.
The sexy plastic switches on the PDP-11 console panel are not easy to toggle, to operate from the bottom or the top of the switch. When you are flipping through a few hundred words of bootloader or debugger, I was way faster on simple, metal toggle switches. I will try to find a better example, there are a number of these demonstrations on YouTube: this video