Sinclair ZX81: 30 years old

Rampack wobble

fixed with a match jammed in for anyone who didn't buy a vastly more stable memopak

re: Legendary

Not even that... Look at a ZX81 and then look at the mobile phone in your hand!

I've been doing some work with microcontrollers recently, and even those £3 chips have 32k of EEPROM, 2K of RAM and run at 16Mhz! It does amuse me no end, but the tight assembler programming habits I picked up from years of 2Mhz 6502 coding on my BBC micro has stood me in good stead.

A Happy Coincidence

Walked into a charity shop today and found a hardback copy of The Complete Spectrum. Score!

Doing down a rare success

I'm not sure anyone's claimed Alan Sugar as a visionary. There's loads of tales of his early days and some of the interesting bodges used to make Amstrad products 'better' - but that's a separate post.

As for Sinclair - yes, he was lucky, but he was in a market where there were hundreds of other people trying to be as lucky, and failing. It's easy to forget in these days of near-two party OS politics, that alongside the ZX81 and Spectrum were devices from Jupiter Cantab, Oric, Tandy, Commodore, Newbrain, Dragon, Elan, Atari, MSX and a dozen others - each completely unique and incompatible.

Sinclair's skill at the time was getting more bang for less buck than virtually any of his competitors. He pushed components beyond their limits, made use of quirks in their specs and pulled together innovative technologies to deliver something unique. It was a scattergun approach that had as many failures as successes, but before commoditisation removed much of the advantage, he was putting home computers into the home. There has to be huge credit to the teams that worked on the machines - from Rob Dickinson's wonderful industrial design through to the FPGA and OS that ran inside.

Of course the industry changed massively and that shook Sinclair, Acorn and most of the others back down to nothing. I'm not sure that makes them less significant, nor necessarily less visionary. Very few technology companies have survived from those early days to present times, and even those have had disastrous moments alongside the successes.

It's a huge pity that these days we're so risk averse and so keen to ridicule people who're willing to try something different that we have trouble producing such exciting technology. Hold an iPad in one hand and a ZX81 in the other and think what could have been.

Title

"It's a shame kids today don't have that immediate access to a programming environment. Lots of fun to be had once you get your head around variables, reading keyboard characters using INKEY$ and moving things around using PRINT AT and SCROLL."

They do, although potentially a bigger can of worms than BASIC if exposed to all of it at once. All browsers support Javascript and it only needs a text editor to use. Add in the <CANVAS> element and you can do pretty much anything a ZX80/81/Speccy could do.

The bit that is lacking is resources to teach it at such a simple level. Most JS tutorials either assume prior programming knowledge and jump straight in to talking about objects and anonymous functions, or are aimed at designers so focus on DOM and HTML interaction. I haven't seen anything aimed at using it as an introduction to general programming.

You're right

Though you can still get kids into programming if you show them Scratch (scratch.mit.edu) which is a drag and drop programming language which lets you do graphics, animations and sound very easily and teaches you the fundamentals of program design. Say it quietly and you can even use it to do message passing and parallel processing (of a kind).

Sooner or later they'll hit the limits of Scratch, but by then they might be hooked enough to go on to a more powerful language like Alice.

And kids today have LEGO Mindstorms which really is far too good for them.

@stucs201 re. MK14

Are you sure it was a MK14? Many universities used a KIM-1 (produced by Commodore, at least at the end), which was a similar product but used a MOSTEK 6502 rather than the Nat. Semi SC/MP which is what I believe was in the MK14.

I remember having to write a sine-wave generator on a KIM-1, and I managed to get a higher resolution wave than everyone else by having a lookup table with just 1/4 of the whole cycle in the lookup table, whereas everybody else had at least a half cycle (and some of them stupidly coded the whole cycle). Fitting it into 512 BYTES was a real challenge. But then I also managed to write a simple lunar lander on the Sinclair Cambridge programmable calculator in just 32 program steps!

hehe...

Oddly enough I was just playing Manic Miner... On a spectrum emulator on my mobile phone! I bet it's got loads of delay looks to stop the 800Mhz ARM processor running the emulation of the 3.5Mhz Z80 too fast!

Firebirds

I spent so much of my life on Firebirds that it's actually quite scary. That and AD Astra, Trans Am, Hunchback...