In which I switch on a 30 year old computer and it just works
jgc.org
jgc.org
If you did the same with a 15 year old 486 and read a bunch of 3.5" floppies (or worse, zip disks) I would be much more impressed :)
Eletronics back then were built to last, and the size of an individual bit on a medium from those days was large enough to withstand decay by auto-demagnetization better than anything new. Lucky you did not have any 'copy through' effects on the tape, that's the biggest killer trying to read old tapes.
THESIS & PAPERS 15 FEBRUARY 1996 ZIP FORMAT / DOS
Externally it looks in good condition, but it's been stored in a box of other junk all that time. Tomorrow I'll take it to work and shove it in one of the machines there that still has a floppy drive and see if it's readable.
I still have one of the first bernoulli 10MB removables here, I wonder how good they would fare. Not much point to try to find an adaptec 1542 just to satisfy my curiosity though.
You mention a bbc micro somewhere, do you still have that one ? (elite ???)
That's one of the nicest computers there ever was to start learning on. The lowest barrier to entry and some of the best books.
My 'growth path' was KIM-1, TRS-80 pocket, then the bigger trs stuff, then an english color computer clone called the Dragon 32, then a beeb, Atari ST and from then on IBM pc's.
At some point a company that I was partner in also had a PDP 11 but we did not do too much with it because of the power requirements, that was my first unix experience.
If you need a system that's reliable for decades (like a pension system), you probably should also think about how are you going to keep the system running after the current hw arch is discontinued and people knowing the specific programming language are retiring.
Nostalgia is great but I don't really care if my intel pc that I replace once a year lasts for 5 years or 30 years.
So, I hope it will reverse, but I fear that it will get worse first...
I'm not sure how much LCD monitors last, but CRTs are known to work well for very long periods of time. I'm sure nobody wants CRTs these days, but I thought this fact was worth pointing out.
Oh, and I hear Apple's hardware is pretty good. In one year of heavy use, my MacBook has never ever failed me even once. This, of course, depends on how you handle your laptop. Mine never goes out of the house, so it's never exposed to shocks, dust or intense heat.
My point is, with a bit of thought, it's possible to build a PC that can last for quite some time.
> Then I did the real test. After poking around and finding a tape of my
> old BASIC programs I typed LOAD again and explored the tape. 30 years on
> all the programs loaded from tape just fine and executed. I was able to
> spend a happy few hours playing character-based games that I wrote.
That his programs loaded after 30 years on a cassette tape makes some of those cheap flaky CDs' lifespans look pretty bad.
Wouldn't say same for the drive used though, and that's where the real problem kicks in.
I recently digitized some old favorite audio cassette dubs (TDK SA, most made on really good gear) and apart from atrocious wow-and-flutter, the high-end was completely gone on most, down to about 8K anyway.
Tape may still be the safest bet to store data long-term. I've read recently that (burned) CD's over 10 years old are getting iffy. Whereas people are still recovering NASA data off tapes made 45 years ago.
I got into the habit of loading up games then entering the debug console and poking in random points in memory. As they say: It's ROM, you can't break it!
But I broke it! I rebooted and found the caps lock in the debug console was broken (but did still work in BASIC). caps lock never worked again in the debug console.
I think it's pretty bizarre to accidentally rewrite a ROM chip, but amusing too.
Of course, it's entirely possible that writing to the ROM was decoded separately and used for some control signals. The Apple ][ I believe did some interesting address decoding to get control signals from the address bus.
Looking at the memory map for the MZ-700 it appears that it implemented bank switching so that the ROM could be paged in or out and replaced with the video RAM and I/O ports. Some of those I/O ports are connected to the keyboard.
Further, there were virtually no games for it.
When I got a Commodore 64 for my birthday, I was very glad to ditch the Sharp and enjoy a REAL computer.
It's more of an observation than a 'law' as such.
In its simplest form it says 'technology gets cheaper, smaller and faster over time', there is nothing you can do about it, it will happen. Social acceptance and momentum don't enter in to it, it either is like that, or it isn't.
Hardware designers do the very best they can, if they could they would prove GM wrong whenever they could, but they can only work so hard and the market is only willing to pay a certain premium for a certain improvement in speed/size and so on. After the early adopters have paid the way the tech becomes mainstream, the price drops and the cycle repeats (it really is executed several times in parallel with staggered outputs, one 'thread' for every big chip manufacturer, that's where all the leapfrogging comes from).
This is about as market driven a process as you could possibly find on planet earth.