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Old 22nd May 2020, 8:14 pm   #41
samjmann
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Default Re: Early personal computers - what for?

stevehertz, you've pretty well summed up where I was back in the early eighties with computers. Like you, I could see that you could learn about them with the basic games etc, but as for using them in everyday life, I didn't really see the link. I stayed in the servicing trade as the thrill of getting something back to life was a real buzz, and is so still today. That said, I should have pushed myself more into the computing side of things during the eighties, as clearly that's where it was all headed.

Computing has changed the servicing trade in many ways for the good, just look at the number of trees saved from conversion to service manuals by the PDF! Up to quite recently there were engineers who were still very 'digital afraid' and refused to learn, but their days are numbered. I use my old laptop every day, have fixed it a couple of times, but still find a computer a means to an end, rather than an interest in it's own right.

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Old 22nd May 2020, 8:21 pm   #42
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Default Re: Early personal computers - what for?

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Personal computers were just toys/games machines. Real computers ran off 3 phase supplies, had disc drives the size of washing machines and cost half a million quid. You knew they were real computers, because you couldn't see over the top of them

Cheers

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........and your App was a stack of punched cards that was at risk on a rainy day as you carried it to the building housing the magic machine which was heavily protected by a layer of bureaucracy. acracy

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I'm not going back THAT far. Thirty five years, not fifty The bureaucracy still applied though.
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Old 22nd May 2020, 9:59 pm   #43
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Default Re: Early personal computers - what for?

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Thirty five years, not fifty
It's about 41 or 42 years since I had the occasional date with a Durham terminal of the Northumbrian Universities Multiple Access Computer and a pile of punched cards. I think the beast itself lived somewhere in Newcastle.

I'm another who couldn't see any attraction in a personal computer until much later on, the end of 2003, when after a friend finally persuaded me to acquire one I promptly signed up here and within a month had launched the Hacker Radio Group.

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Old 22nd May 2020, 11:05 pm   #44
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Default Re: Early personal computers - what for?

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I programmed an assembler routine that was then installed in one of the spare EPROM slots used for downloading ambulatory ECG recordings off a tape recorder, summarizing the data and making it available for the clinicians to use
You may as well be talking Swahili. No disrespect meant to you my friend of course! just once again, telling it like it is! I'm the fool. And yet I don't feel I've missed out on anything? I mean, you can only do so much in a lifetime and I guess I didn't have 'time' to do programming and coding. But.. I've done a lot of other stuff that maybe others would be envious, especially in the 'vintage audio & visual equipment' field. We're all different.
Wow! Bit abrupt Steve.

Not the greatest reception to our new forum member. Swahili?

Matherp is recounting interesting vintage technology of, I guess, 40 years ago. Up to you if you’re not interested in grasping it, but this is how today’s processor based electronics began. I guess that this will constitute an increasing proportion of forum content of the future - no doubt alongside continuing interest in grid leak detectors, tuned circuit Q values and output transformer ratios.

Electronics is always moving on. We’re a broad church.

Martin
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Old 22nd May 2020, 11:32 pm   #45
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Default Re: Early personal computers - what for?

I started out on home microcomputers around 1978 with a Nascom 1 in kit form that I greatly expanded on. I loved the microprocessor hardware and also the associated Z80 machine code.

At an amateur level I dabbled with machine code, assembler and some high level languages like BASIC, Pascal, PLM & C.
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Old 22nd May 2020, 11:46 pm   #46
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Default Re: Early personal computers - what for?

I think the Z80 is the P-51 Mustang of 8-bit microprocessors - The Z80 has such a luxurious instruction set for a processor of that era. Mind you, there are those who think the 6809 is better - not one I really played with.
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Old 23rd May 2020, 12:21 am   #47
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Default Re: Early personal computers - what for?

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Wow! Bit abrupt Steve.

Not the greatest reception to our new forum member. Swahili?

Matherp is recounting interesting vintage technology of, I guess, 40 years ago. Up to you if you’re not interested in grasping it, but this is how today’s processor based electronics began. I guess that this will constitute an increasing proportion of forum content of the future - no doubt alongside continuing interest in grid leak detectors, tuned circuit Q values and output transformer ratios.

Electronics is always moving on. We’re a broad church.

Martin
Absolutely agree.

Steve.
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Old 23rd May 2020, 8:14 am   #48
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Default Re: Early personal computers - what for?

I must admit to preferring to write programs in assembly languages (a symbolic representation of the machine code), as they give a direct control of the processor that is lost in high-level languages such as BASIC, C, C++ and the multitude of others available. The only downside to assembly languages is that each is specific to a particular processor, so it involves learning a new variation with different facilities when moving from one sort of computer to another.
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Old 23rd May 2020, 8:31 am   #49
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Default Re: Early personal computers - what for?

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I programmed an assembler routine that was then installed in one of the spare EPROM slots used for downloading ambulatory ECG recordings off a tape recorder, summarizing the data and making it available for the clinicians to use
You may as well be talking Swahili. No disrespect meant to you my friend of course! just once again, telling it like it is! I'm the fool. And yet I don't feel I've missed out on anything? I mean, you can only do so much in a lifetime and I guess I didn't have 'time' to do programming and coding. But.. I've done a lot of other stuff that maybe others would be envious, especially in the 'vintage audio & visual equipment' field. We're all different.
Wow! Bit abrupt Steve.

Not the greatest reception to our new forum member. Swahili?

Matherp is recounting interesting vintage technology of, I guess, 40 years ago. Up to you if you’re not interested in grasping it, but this is how today’s processor based electronics began. I guess that this will constitute an increasing proportion of forum content of the future - no doubt alongside continuing interest in grid leak detectors, tuned circuit Q values and output transformer ratios.

Electronics is always moving on. We’re a broad church.

Martin
Excuse me, if you read what I said I did say "no disrespect meant to you my friend". The comment is clearly made to demonstrate MY lack of understanding, there is nothing nasty at all about what I said. It's all light-hearted, and throughout this thread I have generally positioned myself as the fool. Yes we are all different, and that again is something that I said. Please, do not stir things up!
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Old 23rd May 2020, 9:48 am   #50
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I think the Z80 is the P-51 Mustang of 8-bit microprocessors - The Z80 has such a luxurious instruction set for a processor of that era. Mind you, there are those who think the 6809 is better - not one I really played with.
I've worked with both and I _much_ prefered the 6809. OK, it has fewer registers and instructions, but it makes up for it by a wide range of addressing modes that apply to just about all the instructions. It has (conditional and unconditional) branches with a 16 bit offset (meaning you can branch anywhere in the memory space) and you can access data with an address relative to the program counter. These features mean you can write 'position independant code' -- a program that can run without changes wherever you put it in memory. This in turns means a multitasking operating system is very practical on that processor, there was a thing callled OS9 (nothing to do with Apple's OS of that name) from Microware (not Microsoft) which was very like a tiny unix.

It's a pity the BBC micro didn't use the 6809. Acorn did make a (rare) 6809 processor board for their 'Systems' (the 19" cardcage machines).

In many ways the 6809 parallels the V2000 video recorder. It came out last, and although it was technically superior to its competitors (6502 and Z80 in the case of the 6809 ; VHS and Betamax in the case of V2000), it was too late to make much of an impact. Although the 6809 does turn up in a lot of 1980s embedded systems (there's one in my HP 1630 logic analyser, one in most of HP's HPIB disk and tape units, one in my Facit N4000 paper tape punch/reader, etc..)

As for what is supposed to have replaced the 8 bit home computers to get people into programming, interfacing, etc now, I don't much care for them. The RPi seems overcomplex, while I like unix-like OSes for a lot of things, the linux on the RPi is not a real time system, and to be honest it just gets in the way for a lot of things I would want to do. And I can't find my way round the Arduino documentation. It seems to be far too much of 'buy these modules and plug them together', 'download these libraries', 'write a bit of code' and it works. That's far too high level for me. I do not design by sticking modules together. If I have to program I am happiest at the 'bare metal' -- assembly language, machine code, or microcode.
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Old 23rd May 2020, 10:02 am   #51
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Default Re: Early personal computers - what for?

It's true that Arduino seeks to allow people to 'do' embedded programming without needing any understanding of the underlying hardware, in fact properly written Arduino programs are 'hardware agnostic', they will run on any Arduino.

What you possibly may not have realised is that Arduino does allow going directly to the hardware if required, I recently posted an Arduino sketch to another thread in which certain parts of the AtMega328 processor are directly accessed in order to perform parallel reads from / writes to the ports at high speed.

With regard to libraries, etc, there is no sense in reinventing the wheel if someone else has already written the exact code you need and put it in the public domain. I'm always grateful to find that someone has already done exactly the thing I was about to do, saving me hours of work in the process.
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Old 23rd May 2020, 10:33 am   #52
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Ahhh the missed opportunities of missapplied technology.

I had a Sinclair Spectrum when I started high school. It would have been capable as a word processor but nobody ever used it as such. All of the written work for the Scottish Exam Board Higher Certificates was banged out on an old manual typewriter.

By the early 1990s, my university essays had graduated to an electric typewriter-with 20 character display and 10 page memory! Banks of 386 (!) machines with either DOS or windows 3.1 had just begun to appear at university, but they lacked the student convenience of working from bed.

When I started working, (1993) we had a typewriter each, and a 286 DOS -based computer between two . BUT we also had a typing pool - which saved much time, quality, tipex, and triplicate paper. (We also had access to telex and fax, mainly for issuing press releases) . In 1996 I was still using lettraset, spraymount and graph paper on an offset litho printing press for leaflets etc.

But the point remains. My 1984 Spectrum would have been capable of word processing. But was only ever a games machine, and for more than a decade, in both education and industry, we used various workarounds for written material when I actually had the technology necessary. And that was commonplace. Why?
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Old 23rd May 2020, 11:10 am   #53
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Default Re: Early personal computers - what for?

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I think the Z80 is the P-51 Mustang of 8-bit microprocessors - The Z80 has such a luxurious instruction set for a processor of that era. Mind you, there are those who think the 6809 is better - not one I really played with.
I've worked with both and I _much_ prefered the 6809. OK, it has fewer registers and instructions, but it makes up for it by a wide range of addressing modes that apply to just about all the instructions. It has (conditional and unconditional) branches with a 16 bit offset (meaning you can branch anywhere in the memory space) and you can access data with an address relative to the program counter. These features mean you can write 'position independant code' -- a program that can run without changes wherever you put it in memory. This in turns means a multitasking operating system is very practical on that processor, there was a thing callled OS9 (nothing to do with Apple's OS of that name) from Microware (not Microsoft) which was very like a tiny unix.

It's a pity the BBC micro didn't use the 6809. Acorn did make a (rare) 6809 processor board for their 'Systems' (the 19" cardcage machines).

In many ways the 6809 parallels the V2000 video recorder. It came out last, and although it was technically superior to its competitors (6502 and Z80 in the case of the 6809 ; VHS and Betamax in the case of V2000), it was too late to make much of an impact. Although the 6809 does turn up in a lot of 1980s embedded systems (there's one in my HP 1630 logic analyser, one in most of HP's HPIB disk and tape units, one in my Facit N4000 paper tape punch/reader, etc..)
I used the 6809 and OS9 in my first proper job in 1984 and agree that the 6809 instruction set is much nicer to use than the Z80. It's a step along the way to the 68000 family.
In my second job in '85 I looked at OS9-68K as an alternative to running Unix on 68010 based boxes. For some reason, OS9-68K ran so slowly on the hardware we were using that it offered no advantage at all and the idea was abandoned.

John
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Old 23rd May 2020, 11:42 am   #54
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I found the ZX81 invaluable, it had an excellent morse tutor programme, that's what enabled me to get my HF licence.

Peter
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Old 23rd May 2020, 11:50 am   #55
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Default Re: Early personal computers - what for?

Why did people buy early-ish personal computers?

Well at one point the vendors used a trick out of the encyclopaedia salesman's repertoire.

"You need to buy your family our encyclopaedia/computer or else your kids will all grow up thick."

Yeah, right, and the kids used that BBC model B for 100% playing games, didn't they? As did their father?

One local amateur was a serious type and he wrote software for tracking satellites which got circulated and used widely in a cut-down form. Unfortunately he wrote it for the Sinclair QL.

My first computing was submitting card stacks for the acolytes to run on the ICL1403 at uni, and typing basic into a 4-bit DEC Minic in the EE dept lab. 4 Bit

At HP i started doing real work on an HP 9810 desk top programmable calculator (inc thermal printer like a cash register width) It was on a trolley with a telescopic whip and flag so you could look around the lab and find it.

9820 was a step up. THe 9825 was getting good. Others hogged the 9835 for one project but I did get the use of a 9845 from time to time. I was writing stuff for control theory, analysing PLLs and doing circuit design. I wrote my own 'Matrix Masher' for the 9845.

The HP85s were another step along the road and I had one to myself for a couple of years while prototyping the HP3708A and planning the modus operandi of its 6809 firmware (I didn't write the firmware, but the trial stuff and sorting all the I/O became my master's dissertation)

I had various hand-me-down Unix workstations and then I bought a PC for home. Ti'Ko assembled in beautiful downtown Broxburn. 486DX33 230 meg disc, 8 meg RAM and a couple of 3.5 inch Sony floppies. Win 3.1 and DOS5. Bought Word5 and used it to write the oscillators and synthesisers chapter for the ARRL handbook.

THis machine got a new motherboard and more memory/bigger disc, NT5 and a copy of tomb raider.

That was replaced with a shiny new Apple iMac G5. Power PC - Well named processor, it certainly used power and it all came out as heat. The waypoint with this machine was my first home internet connection. Pipex as ISP

After some years, the fan speed controller sensor (on PPC chip) failed and I moved to one of the Intel iMacs. That ate a graphics card under warranty, the a connector failed to the backlight in one corner. Apple fix £600 new display. My fix, 2 hours, some microsurgery with scalpel and tweezers, a dod of solder and voila! Eventually the second graphixs card failed just like the first. Bad solder under a BGA. No spares available. So along came the iMac in front of me.

David
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Old 23rd May 2020, 12:58 pm   #56
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I had a Sinclair Spectrum when I started high school. It would have been capable as a word processor but nobody ever used it as such.
EERRRRP!! Wrong, I'm afraid. The Spectrum, like virtually every other computer ever, had its 'power users'. Those of us who had microdrives (and managed to keep them working for long enough) ran productivity software like TASWORD which even generated its own high resolution font.

All my written correspondence in that period was composed on the Spectrum and laboriously eaked out in 'Letter Quality' mode on whatever dot-matrix printer I had at the time. There were programs which would print out a text file as a graphics image so it looked exactly like typewritten output. Very slow, but unlike me, typing, it didn't make any mistakes.
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Old 23rd May 2020, 1:36 pm   #57
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Why did people buy early-ish personal computers?


At HP i started doing real work on an HP 9810 desk top programmable calculator (inc thermal printer like a cash register width) It was on a trolley with a telescopic whip and flag so you could look around the lab and find it.

9820 was a step up. THe 9825 was getting good. Others hogged the 9835 for one project but I did get the use of a 9845 from time to time. I was writing stuff for control theory, analysing PLLs and doing circuit design. I wrote my own 'Matrix Masher' for the 9845.
I prefer the HP9810 to the HP9820 (I have both, still operational) but then I prefer a stack-based calculator even though the HP9810 is like the HP9100 and doesn't have automatic lift and drop.

The real 'step up' in the family is the HP9830. Same processor [1] but with BASIC in ROM, a full QWERTY keyboard and 32-character alphanumeric display). OK, a fairly minimal BASIC (no strings, for example) but still BASIC. And there were add-on ROM modules to add strings, matrices, extended I/O commands, plotter commands, etc. In many ways it's a strong contender for the title 'first personal computer'

[1] 4 PCBs of TTL and PROMs (80 ICs total or thereabouts) making a bit-serial 16bit processor.
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Old 23rd May 2020, 7:54 pm   #58
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These features mean you can write 'position independant code' -- a program that can run without changes wherever you put it in memory. This in turns means a multitasking operating system is very practical on that processor,
I did exactly that when I worked for an Automatic Test Equipment manufacturer in Chichester, I wrote a multitasking operating system for the 6809. It could run 10 differents tasks and switched between them on interupt - hardware or timer. It used some fancy manipulation of the stack to achieve it.
I was very proud of it but it was soon replaced by the 68000.

Peter
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Old 23rd May 2020, 10:33 pm   #59
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I am much like some others here. I could not see the point of taking something analogue and converting it to digital then back again (CD players), and those little early things meant nothing to me. In 1989, my circumstances changed, and I had to find a job. Mostly simple audio stuff, but there were many of these things needing repairs as well. C64s, BBCs, Spectrums etc.. Fortunately I was working with a guy who was bright, and UNDERSTOOD computers. He used to read the "BOOK" on the 6502 whatever that was, and having worked for Amstrad, was fully conversant with all their stuff. He taught me how to locate faulty RAM (though I did not really know what it was). He taught me stuff like "Print, POKE etc" by which he could say WHICH RAM chip was faulty (I wrote it down, never understood it) and so it went on for 8 months, then circumstances forced me to leave and back to the UK. Before I left, the Boss had given me a Commodore PLUS4. A better replacement for the Commodore 64 that never caught on, so it was worthless new old stock. It had a built in word processor, and I managed to pick up both a floppy disc and a printer (7 pin DM type) and with that, I wrote a few articles for John Reddihough in TV mag.
Later I picked up an IBM XT with DOS and Wordstar, making the Plus4 redundant. Since then, I regularly updated what I had, but ONLY to use. The hardware side I mastered, but never the software.
Next I found myself having to repair CDs, and finally understood the apparent nonsense of taking an analogue signal, converting it to an 8 bit, then converting that into a 14 bit version. What a palaver that seemed, but in due course i "got it", with the result that we got back to the analogue world after all at the 'speakers.
I later returned to the Isle of Man and the same employers, now computer stuff only, building something less than two thousand PCs, but studiously avoiding the software wherever possible.
Now I use various software programmes to do my bidding, all courtesy of a Linux operating system. I have learned a few command line routines (but all copy and paste), still not understanding any of it.
Les.

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Old 23rd May 2020, 11:04 pm   #60
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Default Re: Early personal computers - what for?

At primary school and my early at secondary I used BBC Micros, which were always a good machine for introducing someone to computing.

My parents bought an Acorn Electron for Christmas which when not used for playing games was easy to write simple programmes for.

Later my school got some Acorn 3000s which seemed a bit jump in computing power but still fairly user friendly.

At the same time my parents bought an IBM PS/1, which was a mixed bag, being DOS based but having Works pre-installed, which helped building up my word processing and spreadsheet skills. It was still working OK in 2004 when I was on parental orders to get rid of it. I still have the hard drive & mouse from it somewhere.
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