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Apple II DOS source code
- mkhalil 11y agoCool article. Must of been one hell of an smile on their face every time DOS ran on the machine properly after being assembled on a separate machine. Q̶u̶e̶u̶e̶ Cue the person looking at source code mentioning something along the lines of "this is real engineering".
- tome 11y ago("Queue the person ..." - "Cue")
- justinator 11y ago> Queue the person looking at source code mentioning something along the lines of "this is real engineering". Well it's assembly, so I'm looking at it and thinking, "Yup, that's assembly!"
- colejohnson66 11y agoOperating systems today are still marvelous feats of engineering despite their quirks (such as legacy "features" like ANSI and UCS-2 "Unicode" in Windows), the fact that in the past we could fit an entire operating system AND running applications in one megabyte of RAM is remarkable!
- pklausler 11y agoMegabyte? Luxury! Lots of cool systems fit in 64KB, including PDP-11 UNIX.
- cgh 11y agoLike my sibling poster said, a full megabyte would have been the sheerest luxury. After the ROM was mapped into memory on startup, my C64 had 38 kB available for programs. It is flat-out amazing what people did with that memory, including office software, networking and of course games. Keep in mind that the Apple II originally shipped with 4 kB.
- Tloewald 11y agoThe Sinclair Cambridge ZX-80 (sold here as the Timex computer or somesuch) shipped with 1kB of RAM. That said, it wasn't really usable for much beyond programmable calculator kinds of stuff. With a 16kB expansion it was pretty awesome.
- ianmcgowan 11y agoMy first computer! I was programming in Z-80 assembler, typing in listings from magazines, with no way to save the code. So once the machine was switched off, the program was wiped and it had to be entered again. It's one way to learn the importance of accuracy - after hours of typing hex digits, to have one type cause the program to blow up, and have to start all over.
- incepted 11y ago> Must of have
- mhewett 11y agoThe Wikipedia entry for Jef Raskin has further discussion of "Notzo Basic". It was a project by Jef that was never completed.
- juliangamble 11y agoThere is some more about Notzo basic here: http://www.laughton.com/Apple/Apple.html http://www.laughton.com/Apple/Apple.html and here: https://s3.amazonaws.com/s3data.computerhistory.org/atchm/documents/Apple_DOS_meeting_5Oct1978.pdf https://s3.amazonaws.com/s3data.computerhistory.org/atchm/do...
- jonny_eh 11y agoMy mind is blown that they used punch cards to write Apple II software in the early days.
- pvg 11y agoOnly very, very early system bootstrapping stuff. Beyond that, most software was written on the machines themselves. Like this guy, who is also on HN http://www.atariarchives.org/deli/cottage_computer_programming.php http://www.atariarchives.org/deli/cottage_computer_programmi...
- spilk 11y agoWoz is fairly well known to have hand-assembled (on paper) the ROM monitor for the Apple II, which he then used to code Integer BASIC.
- coldcode 11y agoI remember 6502 assembly fondly, so easy to learn and remember, but so full of tricks you had to learn as well.
- jimmaswell 11y agoI don't remember any tricks from working with NES 6502 assembly, what tricks do you mean?
- pvg 11y agoCould you write self-modifying code on a NES? If not (or not typically) that would get rid of most of the crazier stuff.
- Narishma 11y agoCode on consoles of that era is typically executed directly from ROM, so you'd have to first copy it to RAM, which was rather limited (only 2 KB I believe on the NES).
- jimmaswell 11y agoSome carts also had expansion RAM in them also
- StillBored 11y agoHmmm, whole article about people reverse engineering apple dos, and no mention of "Beneath Apple Dos"? That ended up being one of my apple ][ books that nearly fell apart.
- incepted 11y agoDon Worth and Pieter Lechner were idols of mine at the time. I would never have been able to crack a single floppy back then without this wonderful book. D5 AA 96 forever.
- riprowan 11y agoCame here to point this out. My Apple ][ shipped with "Beneath Apple DOS", the Apple ][ programmer's guide, and the Apple ][ Reference Manual which included a full fold-out schematic! The original Apple ][ was more than a computer, it was like a degree in computer science if you actually studied what shipped with it.
- DonHopkins 11y agoWoz autographed my spiral bound Apple ][ reference manual "Have fun with your Apple! -WOZ", so I followed his instructions, line by line.
- deleted 11y ago[deleted]
- incepted 11y agoAnother interesting side effect of Apple DOS is the extraordinary fertile ground it created for software companies to copy-protect their applications. Piracy was already a big deal back then and pretty much every single software publisher on the Apple ][ had developed their own copy protection mechanism by simply hijacking the low-level vectors of Apple DOS. Some of these copy protections were quite frankly amazing in ingenuity.
- riprowan 11y agoThe strategically-placed hole-punch through the diskette will always be my favorite.
- buserror 11y agoMy own favourite was the quarter track 'spiral' protection! It was amazing, and sounded so cool :-)
- walshemj 11y agoWhen I worked in that area for Apple][ copy protection we had a separate card that was plugged into the expansion bus.
- DonHopkins 11y agoI spent so many hours watching The Locksmith [1] go "Read..." "Analyze..." "Write..." nibble by nibble, sector by sector. [1] ftp://ftp.apple.asimov.net/pub/apple_II/documentation/applications/misc/Locksmith%20User%20Manual.pdf
- Shivetya 11y agowell I guess I will admit to the hours friends and I spent hacking out Wizardry and other games. Wizardry was a pain because it was in effect booting its own runtime, a pascal based one at that. (think it was wizardry that did this). Between the days of NDD on PCs and messing with code on Apple ][ I never realized how much my love for programming was being developed
- Jedd 11y agoI run Debian unstable, wryly observing that I get nervous if any package on my machines is more than 6 months old. While I appreciate that some of this code could possibly be re-purposed for embedded systems or micro-controllers with similar memory constraints, it seems these problems have been well solved several times over in the past 38 years. Yes, there's a surprising amount of 65xx development still going on, but again, is this going to fill any gaps that free software doesn't already cover? Note, I'm not saying this isn't interesting - it very much is. But, at the risk of sounding churlish, is this hubris, or is there some justification for the constraint: > ... we are pleased to make available the 1978 source > code of Apple II DOS for non-commercial use.
- white-flame 11y agoEmulation and production of expansions & 3rd party replacement parts of older home computers often are in a legal grey area regarding permission to use, distribute, or modify the original IP. Permission like this is very clarifying and welcome, and has nothing to do with what you run on your Debian box.
- Jedd 11y agoThanks for the reply (I note lots of non-explained downvotes, which are always frustrating in response to an earnest question). Debian reference was perhaps not useful -- more a comparison for vintage of code in use. I appreciate that it's a grey area, and I grew up coding 6502 & 6510 assembly on C64, hence the interest in reading through the pdf's provided. It's more the 'non-commercial usage is okay' caveat for the release. I genuinely don't know if there's a possibility of commercial use, or, beyond that question, why the restriction would be placed (it seems extremely unlikely it's for financial reasons).
- DebraHart7 11y agoI hope give applebot source code also!
- DonHopkins 11y agoReminds me of all those warm starts on a cold late 3D0G night. TIL the name of that band [1] was suggested by the June Fairchild, the Cheech and Chong "Ajax Lady" [2]. [1] https://en.wikipedia.org/wiki/Three_Dog_Night#Band_name_origin https://en.wikipedia.org/wiki/Three_Dog_Night#Band_name_orig... [2] https://www.youtube.com/watch?v=WREo-_R9uyc https://www.youtube.com/watch?v=WREo-_R9uyc
- nobleach 11y agoWow! I remember reading 3D0G in one of the many apple manuals that came with my Apple ][+ I filed it away in my memory and used it every time I accidentally ended up with a * prompt. It feels good to know others have fond memories of those days too.
- DonHopkins 11y agoThe earlier Apple ]['s would dump you into the monitor instead of Applesoft when you hit the RESET key, after resetting the CIN and COUT vectors which disable DOS, so you had to type 3D0G to warm start DOS, hook them back up and re-enter BASIC. The RESET key was so unfortunately placed, and earlier models had very soft springs, which Apple eventually stiffened in later models, so there was a whole industry of after market RESET key protectors [1] (like a square plastic tube that slides over the key so you have to stick your finger down into it to RESET), to prevent you from having to type 3D0G so often. [1] http://apple2history.org/history/ah13/#13 http://apple2history.org/history/ah13/#13
- chiph 11y agoI think the ][+ was the first one with the stiffer reset spring. The other thing that tripped up newbies was the power light on the keyboard that wasn't a switch (you had to reach around the back left of the unit and fumble for it).