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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."
The PBS Triumph of the Nerds specials have additional information on the early years of the Personal Computer.
I only came here to do two things; kick some ass, and drink some beer...looks like we're almost out of beer.
I remember word processing at the time. Lots of punctuation.
Free, legal music for iTunes users.
TFA shows a picture of an Apple //e, not an Apple ][. To see the latter, look
here.
If you reply, do so only to what I explicitly wrote. If I didn't write it, don't assume or infer it.
Sorry- that wasn't the case. Commodity standard cassette recorders worked really well for storing Integer BASIC and machine language code and they used ordinary cassette tapes that were way way cheaper than floppies, particularly at that time.
It's psychosomatic. You need a lobotomy. I'll get a saw.
back in the days, we survived on virtually nuthin', just one megahertz and a far cry from those gatesy 256 kB everyone was dreamin' of.
You kids of today 'ave it easy. You've got your gigahertz machines with gigabytes o' memory in RAM and on disk, splashee colors, many-button mice, DVD burnahs and tha intahweb, downloading more porn in one day than granpa has seen in his entire lifetime, ehhhehh.
Sniff. Nevertheless... back in da good ole' days we play'd Breakout faster on our lo'ly Apples than you do today with your Penthsium class Linux box'n. How do ya figure this is?
I worked in a computer shop selling computers at the time the apple II came on the scene. The brands around then were Imsai, cromenco, Sol, Northside, and even an altair if you wanted one. With the exception of the comodore pet, they all ran on 8080, 8085 or Z-80.
All had traditional power gobbling transfomer-rectifier-capacitor power supplies. If they had a bus it was an enornmous S-100 bus. None had memory mapped I/O or could interleave graphics and text. If they had disks, they were hard sectored disks. And most important of all none used Dynamic memory natively. You could buy dynamic memory cards as S-100 plug ins but they were not reliable.
Unlike the 8080/Z-80 the 6502 had a symmetric instruction clock cycle and all so there was a free cycle where memory woas gaurenteed not to be accessed every other cycle dependably. (not true of the 8080) This meant you could use that interval to refresh the dynamic ram. Thus one never had to insert wait states or have flaky thing happen when there was an irregular refresh rate. It simply worked.
But Wozniak and co, were even more clever. Why waste that clock refresh? since the duration was the same as the regular memory fecth time, they made it a full fetch. But what fetch that had to increment repetiviely over the upper 8 bits of address space would be useful? The video memory! so they backsided the video memory fetch on that.
Contrary to today having memory mapped video was better than having th e video memory on a graphics card. On most grpahic cards when the CPU was accessing the memory they video card could no and you saw glitches. thus video updates were usualy timed by the CPU to occur in thehorizonatal and veritcal re-trace blanking intervals. very clumsy and slow.
Apple used a switching power supply. the first I had ever seen. it was small, and took up no room. the imsai, altair, cromenco and northside computer were huge and half of them were the power supply. some of the capacitors in those were 8 inches tall and 3 inches in diameter. The switching powersupply made this thing a lighe weight "desktop" freindly unit. you could pick it up and easily move it.
It was partly the use of dynamic memory instead of static memory that made this possible. The power draw on static memory is enourmous. and the memory density on static memory was tiny. plus it was very expensive. it consumed most of the mother board. Today's computers would not be possible without it.
I assumed the apple II was a toy when I saw it's teeny tiny plug-in buss cards. until I looked at it's design. svelt memory mapped cards. all the address space decoding was done by the mother board so you didn't have to waste repetative logic on each card decoding it's own address. same with the power regulation. The switich power supply also gave lower ripple so less regulation was needed.
When apple came out with a disk it was the first reliable soft sectored floppy. I had sold lots of softsectored (8") floppies made by others and saw most of them come back too. Who wants an unrelaible storage system. The apple one worked. and soft secotring made it cheap since it had almost no added electorinics on board. It was all driven from software.
Then of course there was the choice of the 6502. it was a breath fo freshair compared to the 8080. It piplined the next instruction. it used relative jump extensively (calucalting an offset based on a register value not the hardwired instruction). It only had an accumulator and three registers. All the rest were memory mapped to the first 256 bytes of memory. So effectively it had enough registers you could really do something. the 8080 was hamstrung and register bound. and because of the pipelining the 6502 didn't lose any speed for the memory fetch using memory mapped registers.
However even then the MHZ myth was strong. people thought a 4Mhz intel must be faster than a 1Mhz 6502. It was not. nearly all the 8080 instructions were 3 to 5 clock cycles in length
Some drink at the fountain of knowledge. Others just gargle.
audio cassette tapes worked MOST of the time. But they were lower quality and more prone to damage. Also the data cassettes did not have a blank leader tape. thus you could start recording the moment you turned them on and not have to wait some period of time after a rewind to start recording. Finally when the recorder was controlled by the computer and not the human pushing buttons it could rewind and seek by itself. At that time audio grade readhead were not reccomended for fast forwarding the tape as they would be destroyed by wear. computer readheads were hardened.
but in simple fact for simple storage needs audio tapes and recorders sis work well. but there was a slightly higher risk of data loss.
Some drink at the fountain of knowledge. Others just gargle.
IBM saw nothing. They were too stupid worrying that their little "home" computer, the PCjr, was going to take sales away from their lacklustre desktop that they crippled the jr, loading it with non-standard I/O ports and connectors, when in truth it outshone the IBM PC in many ways. The jr died a year later.
Compaq reversed engineered the BIOS, and it was all over for IBM's attempted dominance of the PC industry.
As for "lack of open standards" what do you mean? PCI? AGP? FireWire? USB 1 and 2? DVI? tcsh? bash?
It doesn't mean much now, it's built for the future.
Saying that Apple "blew it" due to not using open standards is to miss a sizable section of the picture. Large businesses held off from buying computers until they had received the Stamp of Approval from IBM. Apple was picked up by many early adopters (schools, small businesses using VisiCalc, etc.), but there was no way that large corporations would rely on such a small company when IBM could deliver on a much greater scale (at least in the minds of those contemplating computer purchases for said companies). Open standards were barely dreamed of by the time the war was over --- they appeared mainly because the war was over.
That Apple survived when the vast majority of their contemporaries failed shows that they hardly "blew it"; that they are making a healthy profit today says that their guerrilla action won't be ending any time soon.
"It's really a shame when you consider the influence they could have had. Personally, I'm just glad that IBM was smart enough to see an industry instead of a market."
That is funny. Really.
IBM did not support open standards. The open standard at that time was the Z-80 or 8085 running CP/M. IBM did document everything in the PC and used commodity parts but they also tried to sue the early clone makers. The first legal clones had to reverse engineer the BIOS and even then it was not 100 compatible. IBM was tricky and had Basic in ROM and the BASICA that you loaded with PC-DOS used part of the ROM. It would only run on a 100% IBM. Eventually programmers learned how to write compatible code so programs would run on most of the clones. If you read computer mags from the time the "standard" test was to run Microsoft Flight Simulator and Lotus 123. If a machine could run those two programs it was good enough.
The IBM PS/2 line was an attempt to STOP the clones. The reason the PS/2 line failed was that the clones offered a cheaper alternative. The PS/2 was technically a better machine than the clones but the lack of add on cards make the clones the better choice. BTW the ps/2 keyboard port, ps/2 mouse port, VGA, and 1.44 Floppy all started with the IBM PS/2.
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
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.
Cheap tapes worked fine for us TRS-80 folks too. The main problem with cheap tapes was dropouts. Since the TRS-80 had motor control, it would stop the tape player when it got an error, and you could usually see the bad spot on the tape that caused the dropout.
--
"Open source is good." - Steve Jobs
"Open source is evil." - Microsoft
Now that's a hoot.
The apple used minimal circuitry for everything. Including floppy. Bit decode was done in software. Which meant that the drives had to be almost EXACTLY the same rotational speed, or they couldn't exchange disks.
As to soft sector being more reliable -- sorry, that's also not true. Hard sector is actually more reliable. Simple put, 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. As to cost savings? The hole detector is in the drive anyway (for either 1 hole, or n holes).
And, yes, my Apple ][ still works.
Ratboy
Just another "Cubible(sic) Joe" 2 17 3061
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.
Wozniak spoke extensively about this period at Apple in a great interview at Gnomedex. It's available in high quality streaming audio on ITConversations: http://www.itconversations.com/shows/detail214.htm l