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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."
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.
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.
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