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The Apple II: The Machine That Started It All
Thomas Hormby writes "The first Apple II was sold on June 5, 1977. It was outfitted with a 1 mhz processor, 4 KB of RAM, a keyboard and a cassette interface. Despite the seemingly paltry specs, the machine made Apple, and bankrolled the LISA, Macintosh and LaserWriter. Besides building Apple, the machine revolutionized the entire microcomputer business, pulling it way from the hobbyist kits and closer to todays PC. Read about it at MLAgazine."
Apples and most other 8-bit computers used standard consumer cassette decks. IIRC, the Apple could not "seek" by itself, you had to plug in an earphone and listen for the gaps in the tape.
Most of us used the "tape counter" three digit counter as a directory. 005: brickout 020: lemonade stand 045: eliza and so on...
It's psychosomatic. You need a lobotomy. I'll get a saw.
(I hand-assembled a lot of Z-80 code back in the day. I never liked the 6502 instruction set much and still don't now that I'm playing with Atari 2600/7800 code. At least the instructions were faster. But the 6809 puts them both to shame.)
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"Open source is good." - Steve Jobs
"Open source is evil." - Microsoft
Only if DOS is installed in the machine.
Ctrl-C Return was the monitor command; DOS would usually get reattached as soon as Basic printed the prompt character and waited for keyboard input. But you could, in theory, totally disconnect the I/O hooks without doing I/O to reconnect them. 3D0G would re-establish the DOS connection cleanly, assuming you hadn't toasted the instruction at $3D0 itself.
The 6502 instruction set is a pain. For my senior thesis, I wrote a dynamic recompiler that translated 6502 code into PowerPC code. Useless? Totally, but fun to see it disassemble code from old Apple II programs and reassemble them into PowerPC code.
If it's not one thing it's your mother.
$60 is an RTS and $EA is a NOP. Both were very handy for "shunting" around the various copy-protection schemes in use on old Apple ][ programs.
I can't count the number of times I sector-edited in a sequence of "EA EA EA" somewhere.
"I feel that if a person can't communicate, the very least he can do is to shut up." -- Tom Lehrer
Interesting commands from ages past...
:-)
XYZZY
Mainframe/UNIX Bit Twiddler and long time Windows/Linux Hobbyist.
The Theorem Theorem: If If, Then Then.
Which meant that the drives had to be almost EXACTLY the same rotational speed, or they couldn't exchange disks.
Not necessarily. Because of the use of self-sync bytes and a required set high-bit for any disk byte, the software decode was remarkably tolerant of speed variations on the drives. I saw Apple II drives whose speeds were 2-3% off from spec still operate perfectly, including exchanging disks with other systems.
if a sector is damaged, it is possible to skip over it, and read sectors after it on the same track. Not possible (with ANY reliability) using a soft-sector format.
Also not true. The Apple II's disk-encoding scheme had a header preceding each sector, with sufficient information to synchronize with and identify each sector 100% reliably, regardless of the condition of any other sector on that track. It was quite possible to have 15 of 16 sectors on an Apple II disk perfectly (and consistently) readable.
"I feel that if a person can't communicate, the very least he can do is to shut up." -- Tom Lehrer
Ah yes, the Apple II. I had an Apple II once, but it was the later, smaller variant, the Apple IIc. I think one of the reasons why I chose to get it rather than an Atari 400, Commodore Vic-20 or TI-whatever, is that the Apple IIc was so small.
Apple kept promising that they would release a small LCD screen that would attach to the back of the computer. Imagine the prospect of having a (semi)portable computer in the early '80s! The LCD screen as pictured in magazines must have been capable of showing just 10 or so lines of text vertically. I never did get to see one of those screens in person.
I know that the personal computers of that era were primitive in comparison to what we have today, but back then there was a certain thrill in using a personal computer. A feeling of exploring new possibilities. Computers were still fairly exotic creatures at the time.
The software was primitive as well, but evocative in its own way: Lemonade Stand (I kid!), Bard's Tale, Zork! I also remember the hours spent in laboriously typing in programs from magazines and books, and hoping that I didn't make a typo somewhere.
It's amazing how much nostalgia you can feel for something which was in every objective way inferior to what you have now.
Anakin Simpson: If you're not with me, then you're my enemy--ooh, donuts!
Nibble was the best (and still is the best) computer magazine ever.
Paired with Softalk, you had an awesome pair.