Slashdot Mirror
Still Life in the Apple II Community
a2fan writes "A bunch of retro-computing Apple II enthusiasts are decending on Kansas City, MO July 22-27 for the 15th annual KFest. Apple co-founder and Apple I, II designer Steve Wozniak will be there. The Apple II keeps on kicking with Ethernet, TCP/IP, and PCMCIA RAM cards used as hard disks. What is it that keeps such an old platform going?"
I don't know if I would call it "joy"...
I would use the term "satisfaction"; I remember being very pleased with myself for coming up with a sixteen bit by sixteen bit shifting multiplication algorithm in just 24 instructions or realizing that self-modifying code is needed to perform an indirect jump or data access anywhere in the 16 bit address space.
If you can competently program the 6502 in assembler, then you will be able to tackle any other 8 bit processor architecture with ease - a very satisfying accomplishment.
myke
Mimetics Inc. Twitter
every once in a while I'll boot up my Apple ][e, plug in the joystick, and fire up Rescue Raiders. The game was fun in and of itself, but I think the real reason I enjoyed it was because it belonged to my dad and he wouldn't let me play it...
The other games I played were this series of text adventure games, written by Scott Adams (maybe of Dilbert fame, we could never find out). There were nine of em, 3 to a disk, and arranged from easiest to hardest. Couldn't beat any of em. heh. They were fun though, especially the second (treasure island) and the third (some mission impossible-type thing where you had a limited number of turns before a bomb went off).
We had em in elementary school, where the teachers let us play games like Oregon Trail; this one where you're a fish and have to eat other fish, and avoid the otter or something; and there was one where you were a geologist and had to identify rare gems by their color, hardness, etc. Anyone remember this game? Everyone I ask about em just kind of look at me.
But besides games, I learned to program on that computer; there were BASIC programs in the back of some kids' magazine I subscribed to, 3-2-1-Contact or something, that taught you about control flow, strings, stuff like that. I remember this one where you ran a zoo with panda bears that kept dying every time you looked at em the wrong way.
man, thanks for the trip back in time there...
the coolest club on
The Apple II can function in cold environments. For instance if you want to control your telescope in an unheated environment the apple II will to the trick.
Back in my day (which wasn't that long ago) Apple IIes were the way to go. In elementary school we were introduced to basic programming using Logo and Logo Writer in which commands could be written in a programming buffer which could draw cool designs and play little songs when you compiled your mini-code on the Logo command line.
In high school ('96), we had a networked set of Apple IIe's (which I re-networked the next year) that were mainly used for labs- both for plotting data and in some cases, learning to program in basic. Our basic programs were labs where we would run quick projectile motion models with varying height parameters (launching something off a cliff as an example) and by adding wind resistance. The labs showed that most of us were really bad at estimating how far objects would travel in non-perfect (ie non-vacuum) conditions. Last I heard the physics lab is still using those machines though the teacher is retiring at the end of the year. . . .
Ok, listen - yes, people like old things. They like old cars, old houses, old paintings. Sure. They can even like old computers. But you know what? Its not because life was better back then.
Apple ][ came out in 1976. The next year, Gerald Ford ended his term (you know, the guy that took over for Nixon...). The economy was in terrible shape, much worse than now. We had just left vietnam a couple years before (1974). The Cold War was HUGE. A radioacive leak occured at 3 Mile Island in Penn in 1979.
Also in 1976, we had Gregg vrs Georgia, in which the Supreme Court of the US decided that the death penalty did not violate the constitutions protection against "cruel and unusual punishment," thereby keeping us in that sad, barbaric state of affairs.
Shall I go on? What in god's green earth makes you think life was simpler and better than now? What, precisely, was better? What was more simple? Was it just because you were a kid, or at least much younger, then? Because nothing about life during that time was something to long for.
Grass is always greener on the other side of the fence, if you're a cow. Personally, I like climate control inside of my car. I like to be able to listen to great sound from a little peice of plastic I slip in a slot casually, without having to fumble with some 8-track or cassette. I like the little things we have now, that we didn't then. Call me odd.
I could never understand why nobody produced a PDA based on the Apple ][. I bet you could compress one down to the size of a Palm, power on an AA battery, stick AppleWorks in ROM and satisfy 99% of what people use computers for.
- Laird "I can't remember my Slashdot ID" Popkin
That old Apple II machine-language monitor was
amazing and the overall simplicity and sensability
of the 6502 was great. I taught myself machine
language by using the mini-disassembler and
puzzling out other people's code. Can you imagine
doing that these days?
It's psychosomatic. You need a lobotomy. I'll get a saw.
Actually, if you opens it up, the simplicity will simply amaze you. It's HACKABILITY that matters. The Apple II was infinitely and easily hackable. That alone keeps it going.
Who'd a thunk it? Here is the closest I could find on Google. There are actually entries dated today. ;-]
"A revolution without dancing is... a revolution not worth having"
Ah...lemonade stand....I lived for those "hot and dry" days...now I live for the sound of "three frags left.." *sigh*
but back to the topic at hand. IN SOVIET RUSSIA, DYING PLATFORM USES YOU!
OMG! Wau!
The 65C02 added indirect and indexed indirect addressing to JMP (previously, only absolute addressing was available).
What I think was my most clever hack was a routine to play WAVs (11.025 kHz 8-bit mono) on an Apple II with no additional hardware. 73 bytes on page 3 was all it took to play sounds through the speaker with a resolution of 4 bits per sample. Source code is here.
More recently (just a few months ago), I wrote some code to communicate with Dallas Semiconductor's 1-Wire devices through the joystick port. I used a temperature sensor and a clock chip to turn a II into a programmable temperature controller for my beer fridge. In addition to maintaining a set temperature anywhere from the 70s down to the 30s, it also manages gradual temperature changes (1/hr) for different stages of brewing--primary fermentation, diacetyl rest, lagering, etc. The code to do all this is GPL'd; I just haven't gotten around to putting up a page on my website for all of it yet (though the 1-Wire primitives are available through this page).
20 January 2017: the End of an Error.
I just want to make sure everyone here is aware of this band,
http://www.epitonic.com/artists/barcelona.html
whose songs include "social engineering", "i have the password to your shell account," and "c64" ("got a modem when I turned 13/But my dad doesn't know what telophony means/only 300 baud/Never leave my room -- isn't that odd.")
good music, too.
I learned to program on the Apple ][, back in 1978. I learned BASIC in about a month, then insisted the school buy Pascal. Then I moved on to assembly (ahh, Sweet 16 mini-assembler, built right in!).
I learned how to program within a month, and within a year was using the built-in mini assembler to write programs that controlled the video directly (for games, of course). I *knew* that machine, inside and out. I could look at a JSR opcode and know exactly which system call was being made.
Today, even programming the most trivial program can take a month. Learning a new system? My nephew (who is the age I was when I started programming, and he's lived with computers almost his whole life) is having troubles learning how to write the simplest program.
Why? Because it's all too damned complex.
People learn using building blocks. Learn the simple concepts first, then build on that knowlege to learn more and more complex things.
Problem is, it's tough to do that with modern computers. I think that is the primary appeal of Linux, to me. It's not as hard to start simply, because the simple stuff is exposed. Overly-complex systems designed to hide the fundamentals will never lead to a generation of people truly *good* with computers. Good with a particular system? Perhaps. But good with *computers*?
Not likely.
That's where the love of the old machines comes from.
Microsoft is to software what Budweiser is to beer.
I got an Applie IIe when I was 10 and taught myself basic. I wrote a bunch of nifty graphics programs and all kinds of stuff. I drew pictures with dazzledraw, and played all sorts of games. I remember dazzledraw had this digitized picture of a room, and I thought it was so amazing, even though it was only 16 colors, and I think 320x240.
Later after I got a Mac LC, my mother gave away my IIe and all my floppies, so I can't see all my earliest digital creations.
SproutWorks Software Design
What is it that keeps such an old platform going?
krog suggested:
Anyone who knows the joy of programming machine language for the 6502 knows the answer.
I'm not sure if krog was joking, but I actually had some fond memories of my teen years when I read this. And I could be mistaken, but I think I still remember how many of my chunks of 6502 code began... "A9 00..."
(For those who only speak Assembler and not ML, that's "LDA #$00")
Aaaahhhhhh... and now I'm remembering my endless tinkering with the little 16-pin joystick socket. I made joysticks, a device to let me use the cheap Atari-compatible joysticks on my Apple, and a cheap substitute for a graphics tablet (using a couple of variable resistors to measure what the pen was doing and let the computer know).
I remember when my mom first took me to a computer store to look at some machines. I was of course looking at various games and things (I was in 6th grade-- would you expect something different from a boy that age?) and my mother asked one of the people at the computer store directly: "is this just going to be an expensive Atari?"
(Note: Mom was referring to the Atari 2600)
The response was cool, and more truthful than I thought at the time, and probably more truthful than my mom thought: "there are games for the computer, and he WILL want them and WILL play them, but the difference is that he won't learn how to program and use computers playing games on the Atari."
Thinking back, I can now see that the employee was right. I did play a lot of games on the computer, but I also did learn a couple of programming languages and started doing something I still do: when I had some kind of problem that would be a pain in the ass to figure out in my head or even with pencil and paper, but relatively easy for the computer to figure out for me, I would write simple programs to do just that. I also got the basic notions of hardware architecture and the confidence of knowing that I am capable of figuring out how seemingly complex devices work and even making my own extensions. I am very glad to have been the owner of an Apple ][. And I also have fond recollections of Commodore machines (VIC-20 and C64) because of a couple of friends who had them and learned 6502-ese with me.
Great days. Thanks for reminding me, krog!
--Mark
"It is nice to know that the computer understands the problem. But I would like to understand it too." --Eugene Wigner
I suspect that many of the remaining Apple ][ enthusiasts are re-living to some extent their first computer experience. A lot of people in adult life try to recapture some of childhood's sense of wonder through collecting toys or pursuing interests that were first sparked when they were young.
My (family's) first computer was a Dell Pentium 3 system, and I've always felt like I've missed out on the entire history of computing. I wish I could have been born a few decades earlier. What kinds of memories will computer geeks of my generation have? Quake 3 just doesn't seem to have the nostalgic qualities of the original Oregon Trail. Or BBS's, assembly language, punchcards, teletype machines, anything involving a soldering iron, etc.
Aaah, educational PC's. I remember learning to type and program on apple IIe's. The setup was amazing, they were all networked to a macintosh which shared a printer.
.net stuff. I thought, "that money could be well spent elsewhere - educators!" But I digress, I'm not a highly paid consultant.
I recently learned a consultant had convinced my school district to spend a lot of money moving to microsoft
Bitter? I share your sentiments. My girlfriend is looking for a teaching position, but there's no funding, wonder why (see above)....
If you attempted to read the cassette-out port on the Apple II+, no (tri-state) devices would actually attach to the bus. As a result, the data lines on the bus acted like a DRAM cache and momentarily "stored" the last value read from RAM (the "vapor"). Since the CPU and video refresh circuitry alternated RAM access every half cycle, the last value read was always one from the current video page.
A few bytes of each hi-res graphics page were read by the video refresh circuits but not displayed (during horizontal blanking, if I recall correctly). By storing "unlikely" values in these bytes, and then waiting for them with a read loop, you could determine where the video trace was in the graphics page and calculate when the vertical blanking would start.
You could flip graphics pages during the vertical blanking interval to get smooth animation, or calculate times to switch modes and mix text and graphics anywhere on the screen (a big deal, in those days).
PS. I realize this dates me, but really, who else would?
Dear Will, the plums were poisoned. -- Cheese Club
You forgot two of the most elegant things the II had going for it.
The graphics system has incredibly simplistic hardware that simply set the composite color burst timings based on the a single bit shift of the video memory. This removed the complicated timing and DA conversions that other early color systems required. Of course it made it a pain to set any given pixel to a specified color, or even draw a line (the video memory wasn't mapped line for line to the screen for timing reasons). It also had some interesting side effects like leaving a couple of unused bytes at the beginning and end of each line which were scanned during the horizontal refresh allowed the programmer to 'hide' information in the video buffer. Eventually with the release of the 80 column card, the graphics system was increased to 16 colors and the horizontal resolution was doubled. My undestanding was that this was completly accidental and discovered only after the card had been on the market for a couple of months.
The other cool thing you sort of touched on was the soft sectored disks. Most disk drives of the time cost a lot of money because they also had complicated timing and encoding logic built onto them as well as sensors for detecting head location and where in the spin the disk was. Some history:The problem with magnetic media (and some communications mechanisms etc.) is you cannot tell were the bits start and stop so you need tight timing, or an encoding scheme which guarantees that no more than a certain number of off or on bits are adjacent. The disk drives for the II didn't have any head or disk position sensors, nor did they have encoding or timing logic. This was all offloaded to the software in the ROM's which encoded the bytes (using 4 by 6 encoding if I remember correctly) wrote the sectoring information (some series of bit patterns guaranteed to be unique with the encoding scheme and guaranteed to allow the software to detect where a byte started) and everything else related to managing the disk drives. This allowed the II disks to have some seriously ugly copy protection schemes (writing data between the tracks, because a track was actually 4 pulses of the stepper motor, spiral tracks, tracks with funny sectoring, funny encoding schemes the list goes on.) Not only that but since you couldn't tell where on the disk you were until you read the sector information, and not all the disks were sectored the same the ROM would basically pulse a full stroke to the stepper motor to locate the first track to boot the machine. This is what that really bad clunky / grinding noise is when the machine is first powered on. Another little trick was that the amount of data you could fit on the disk was related to how fast the disk was spinning (actually this is true of any disk to a certain extent). The software could correct for small imperfections in the rotational speed, but since the on/off timing of the head was directly controlled you needed to adjust the speed the disks spun at for optimum data consistency. Hence those little screw drivers that came with some models, and the disk tune utilities which would show you how fast the disk was spinning while you turned the adjustment on the drive. In the long run it turned out to be an advantage to have such low level control of the disk drive since various pieces of software were written to read other computers disk formats.
I recall using a different version of DOS called "Turbo-DOS" I think it was that loaded programs way faster than Apple DOS 3.3. Obviously that came at a price in terms of what features where available. IIRC the code that had to deal with formatting a floppy was removed from Turbo-DOS so I had to go back to Apple DOS 3.3 to format a floppy.
This was a pain so I wrote my own diskcopy program and using the "Beneath Apple DOS" book I managed to gleen all of the disk format code out of Apple DOS and into my diskcopy program. What a hack as the format code within Apple DOS used NOPs all over the place for timing. I used the Randall Hyde's "Laser Interactive Symbolic Assembler" aka "LISA" to do all of my 6502 coding work on the Apple ][.
open!
Simple as that. There was nothing you could not know about the machine simply by looking at it actually.
Because the system is easily understood, making it do what you want (provided that task is within the limits of the hardware) is easy.
Someone needs to make computers like this today, only with slightly better video. Kids who want to "get good at computers" would be well served learning said machine inside and out.
Blogging because I can...
Very interesting! How do you run the mini-disassembler though?
A couple of years ago, at the Canberra Show, I saw a carnie booth selling Bioryhtms for about 5 bucks each. It was being driven by an Apple ][ plus ... I talked to the sideshow operators, and they had tried to replace it a couple of times with newer computers.
... but the Apple kept chugging away.
The newer computers kept breaking
Woz knew how to build a machine, thats for sure.
Believe it or not, my dad still uses an Apple //c for his business -- he uses it for writing business proposals and keeping inventory on carpentry items. He says that it just works... Even though there is a newer PC in the house, with MS Office on it, he still uses the //c instead. His ImageWriter II dot matrix printer still prints fine, his 180k and 360k floppies still work fine (mainly because the magnetic density is so low that they don't degrade as much with time), and AppleWorks boots up in the time it takes our PC to check its RAM. About the only problem he's had is with finding 5.25" DD floppies (though I've heard that some places sell them by the thousands for cheap nowadays). Anyway, he's been perfectly content using the Apple //c for the last 15 years! How's that for a switcher story?!
Slashdot's first reaction to VMware