Should the Elk have been a 'full' Beeb?

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Re: Should the Elk have been a 'full' Beeb?

Postby algenon_iii » Wed Apr 12, 2017 3:05 pm

Mark - that's pretty what I'd imagine the A+ or A-lectron :wink: to be. Only thing I'd drop is the RGB port (the model A didn't have one as standard I think) and just have TV and colour composite video - more than enough for a home computer.

I suspect that Acorn decided that they wanted a £150 machine (32k is half way between 16k and 48k so price halfway between the £125 and £175 spectrum prices in '82???). I do wonder whether they ever costed an A+ style machine, found they could never get it down to £150 or thereabouts and decided to start from scratch. Perhaps if they'd known it'd be £199 at release they might have taken the A+ route, hindsight...

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Re: Should the Elk have been a 'full' Beeb?

Postby 1024MAK » Wed Apr 12, 2017 5:40 pm

Myself, I would include the RGB video output, as the ULA outputs the three colour signals anyway. All that is needed is for three transistors and some resistors to buffer the signal. At current prices, transistors cost less than 10p each...

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Re: Should the Elk have been a 'full' Beeb?

Postby B3_B3_B3 » Thu Apr 13, 2017 10:43 am

As using the BBC/Apple style of CRTC/CPU interleaved memory access which requires double the memory bandwidth (ie 4Mhz for the 2Mhz beeb): I wonder whether it was less suited to the electrons 4bit RAM-------

Supposing instead the 'CRTC' ULA used the Spectrum 'video ULA as master of shared video ram area style':----

The CPU access speed to uncontended memory below the current video ram area could run at full speed (ie equivalent to 2Mhz on bbc): the important zero page, stack, and program area would all be at this full speed. Access to video ram might require a processor halt unless programmer deliberately writes during flyback period (don't games often do that anyway to avoid flicker?).

better suited as well as simpler to implement?

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Re: Should the Elk have been a 'full' Beeb?

Postby Coeus » Thu Apr 13, 2017 1:49 pm

On the question of having 4 64kx1 memory chips to give 32Kbytes why are dynamic RAMs typically one bit wide whereas ROMs are 8 bits wide?

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Re: Should the Elk have been a 'full' Beeb?

Postby Rich Talbot-Watkins » Thu Apr 13, 2017 4:57 pm

Yes, my 'fantasy' alternative hardware spec for the Beeb/Electron was always to have the screen memory in a bank from &8000-&C000 (so a 16k 25 line screen). Not like any other sideways RAM bank, but something special which the video ULA has preferential access to, with contended CPU access. It would free up the whole of the 32k of RAM below, and would presumably save having to clock the RAM so fast.

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Re: Should the Elk have been a 'full' Beeb?

Postby B3_B3_B3 » Sun Apr 16, 2017 12:02 pm

It seems you could get BBC BASIC for the 64:
http://mdfs.net/Software/BBCBasic/C64/
:)

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Re: Should the Elk have been a 'full' Beeb?

Postby B3_B3_B3 » Sun Apr 16, 2017 12:42 pm

1024MAK wrote:One thing to add: a cut down BBC with extremely limited on-board expansion and so a PCB half the size. Say a 32k model A equivalent as far as software is conserved (see below) called a A+. And a less powerful and less expensive power supply. It could have been able to have been brought to market a lot quicker than designing a new computer like the Electron.....

Yes, I agree:

Keeping the BBC case (or atom case) would allow the keyboard layout to remain the same
(good for swapping between school Beebs and home), although perhaps the shift lock* key could become a FUNC key so that the orange function keys could move to the electron position (cost saving), and perhaps use better cursor arrow key layout.
If the same case and exactly the same keyboard layout as BBC B was used, you could upgrade by swapping the PCB and fiting internal PSU, changing Badge to BBC.....

*Well I never used it :)

Perhaps as cheap as possible for the minimal required features would have been a better aim rather than aiming to match the Spectrum price no matter what.

Either all modes 0..6, or if mode 0 caused trouble with ULA timings (Steve Furber mentioned it did on the real elk ULA), then just drop it.

I wonder if an optional upgrade to shadow RAM would be more useful/perhaps simpler than mode 7 support: and would perhaps have encouraged an earlier B+ model..... With shadow RAM some limited colours mode 7 emulation could be done by OS.

Seek other compromises rather than 4 bit RAM.
Eg a CRTC ULA that abandoned BBCs interleaved CPU/CRTC access which required double speed 4Mhz memory bandwidth for the more usual low cost computer style of contended CPU to video RAM access (unless during flyback) which would only need 2Mhz access.

For sound, either full beeb compatibility (preferred) or go for cheapness, even if only a 1 bit beeper, as other features more important in a computer whose main feature is BBC BASIC, compatible graphic modes...

As, most would be only ever connected to a TV, don't waste money fitting monitor components, just bring raw monitor signal connections out on an edge connector expansion or similar if at all.

EDIT some digital input /output lines for apprentice programmers to read /wiggle might be useful
but if too expensive could be a cheap module (optically isolated?) for cartridge port).
I think I've got that all off my chest now :)

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Re: Should the Elk have been a 'full' Beeb?

Postby B3_B3_B3 » Fri Apr 28, 2017 6:07 pm

I looked up Simons' BASIC for C64:

quite BBC like but no cassette or graphics compatibility so an Acorn BBC BASIC cartridge for C64 that included a bbc compatible cassette port and some mapping of 1024*1280 beeb virtual coords to C64 screen might have suited schoolwork while allowing C54 games when off....

I wonder if the profit margin percentage on such a cartridge would be higher than an actual Elk?

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Elk: surely Mode 7 could have been software simulated in monocolour?

Postby B3_B3_B3 » Fri Apr 28, 2017 6:38 pm

I know the Electron just substituted mode 6 for mode 7 and showed garbage for semi-graphic chars etc:

but surely with a separate character set in MOS ROM, a monocolour mode 6- based* software simulation could have been built-in to the MOS?
NB I don't think not supporting Double Height characters or flashing support would be that important.

*Mode 6 but with teletext rather than the usual Ascii character set: Mode 006 and a half?

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Re: Elk: surely Mode 7 could have been software simulated in monocolour?

Postby danielj » Fri Apr 28, 2017 6:51 pm

OK, there's getting to be a bit of a proliferation of these "wouldn't x have been better" "why didn't they do x" "where's the x" threads now. This clearly belongs in the "Elk full beeb" thread. I'm going to move anything in this thread to there once I get a moment. Discussion's great, but a proliferation of similar threads really isn't.

d.

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Re: Should the Elk have been a 'full' Beeb?

Postby paulb » Sat Apr 29, 2017 11:23 am

1024MAK wrote:One thing to add: a cut down BBC with extremely limited on-board expansion and so a PCB half the size. Say a 32k model A equivalent as far as software is conserved (see below) called a A+. And a less powerful and less expensive power supply. It could have been able to have been brought to market a lot quicker than designing a new computer like the Electron.....


The problem is that as soon as you start cost-optimising the Beeb, you start to reproduce something like the Electron. It would be an interesting exercise to consider now, just to see what the possibilities are, and it was said (and I think I did mention) that Acorn were criticised for not reducing the chip count and shrinking the board aggressively enough, which were identified as decent optimisations. The Master does simplify some things, I guess, but it's still pretty complicated, and you could argue that the Compact is really the result of this "optimise the Beeb" project, anyway.

B3_B3_B3 wrote:Yes, I agree:

Keeping the BBC case (or atom case) would allow the keyboard layout to remain the same


The Atom case would have been a reasonable choice. I imagine that the Beeb case was considered far too large for casual home use. You also suggested making the keyboard technology cheaper, which if you review the coverage of the Electron and other computers from the publications of the era will seem like a bad idea indeed: despite the Electron's weaknesses, a membrane keyboard would have made the product completely non-viable because it would have been completely trashed in the reviews, such was the perceived importance of proper keyboards, especially for machines that were likely to be used for more than just games.

B3_B3_B3 wrote:Seek other compromises rather than 4 bit RAM.


You do realise that probably the principal cost optimisation involved, maybe apart from the increased integration and board size reduction, was the choice of cheaper RAM? While Acorn were always miserly with RAM, there was a justification for going with cheaper RAM, just as the Spectrum had done.

B3_B3_B3 wrote:Eg a CRTC ULA that abandoned BBCs interleaved CPU/CRTC access which required double speed 4Mhz memory bandwidth for the more usual low cost computer style of contended CPU to video RAM access (unless during flyback) which would only need 2Mhz access.


I think you mentioned that games only ever write to the screen in the flyback period, which is really not the case because there's not enough bandwidth. And computers with poorly-optimised screen access tended to get heavily criticised and sold badly. I think it was the Camputers Lynx that had apparently impressive video until one realises that the bandwidth for programs to access the screen was the thing that was severely compromised and just ruined the general experience.

B3_B3_B3 wrote:For sound, either full beeb compatibility (preferred) or go for cheapness, even if only a 1 bit beeper, as other features more important in a computer whose main feature is BBC BASIC, compatible graphic modes...


At some point, why bother doing an Electron at all? By the time you've pruned away all the features, you've got a computer that would have needed to be priced somewhat below £100 to sell. Acorn would have almost been better off just continuing to offer the Atom to people wanting a cheap computer with a degree of Beeb compatibility and video capabilities comparable to previous-generation machines. And since Sinclair and Commodore were having a price war, I doubt that this would have been a good idea, either.

The end of this particular decision-making route is to just not bother with the home market and to focus on business applications and the different education markets instead, which is what Acorn actually did, arguably in a belated and unconvincing manner (with regard to the business and higher education markets) until they could deliver ARM-based systems, and even then they never really took full advantage of what they had on offer.

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Re: Elk: surely Mode 7 could have been software simulated in monocolour?

Postby Richard Russell » Sat Apr 29, 2017 11:44 am

danielj wrote:OK, there's getting to be a bit of a proliferation of these "wouldn't x have been better" "why didn't they do x" "where's the x" threads now.

Please no! I can't remember a more frustrating and pointless thread than this one. I've had enough of being told that the BBC and Acorn (and by association I) did such a poor job back in the early 1980s.

Richard.

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The dangers of hindsight...

Postby 1024MAK » Sat Apr 29, 2017 12:22 pm

Richard Russell wrote:Please no! I can't remember a more frustrating and pointless thread than this one. I've had enough of being told that the BBC and Acorn (and by association I) did such a poor job back in the early 1980s.

Richard, I don't agree.

Acorn did a wonderful job with the BBC Micro machines. Compared to the expected demand, Acorn sold many more than they had ever hoped for. If there had not been problems with the production of the Electron, it may have been very successful.

The BBC inspired both programming and the take up of home computers in this country. Which created a market that had previously been almost non-existent, which gave pleasure to many, helped educate others and provided jobs.

And BBC BASIC may be falling out of favour now, but it IS one of the best ever versions =D>. In the 1980s the only real rival was the QL's SuperBASIC. Since then, the only BASIC like language that is better, is OPL on Psion machines.

At some point, all the U.K. home computer companies had problems. For a new and dynamic market with lots of competition, price wars, and memory prices changing all the time, it's hardly surprising many companies did not get it right. Acorn were one of the better companies.

And to put threads like this in perspective, similar threads have popped up on forums for various other 1980s home computers. People just love playing "what if". But rarely do they consider everything that was relevant at the time that the people of Acorn made their decisions.

These threads are good to discuss such speculation. As some answers can be given. Of course, these threads are heavy coloured by the benefits of hindsight. At the time period that we are talking about, the Internet as we know it did not exist. Data sheets for chips were sometimes hard to get hold of. And that assumed that you had discovered that particular chip...

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Re: The dangers of hindsight

Postby Coeus » Sat Apr 29, 2017 1:18 pm

I don't mind the "What if things has been done differently?" but then, as I wasn't involed in the decision making, I don't feel like I am being attacked. Doing this kind of "What if?" exploration may even be educational.

For me, every person who was involved and whom I have listened to or read has come cross as bright, well educated and supremely competent. If one looks back and a particular choice is puzzling it will be for one of the following reasons:

1. There was some aspect of the times concerned that was familar to those involved but which is not something we tend to think about now.
2. We now have the benefit of information that was not available at the time.

and I think, despite hindsight being a wonderful thing, we're finding more of the first than the second.

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Re: Should the Elk have been a 'full' Beeb?

Postby Elminster » Sat Apr 29, 2017 2:02 pm

The only person in the 80s who seemed to have a crystal ball was Alan Sugar, he seemed to managed to always get it right (or righter than anyone else), you have to wonder what the scene would have looked like if he had got in a couple of years earlier.

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Re: Should the Elk have been a 'full' Beeb?

Postby Commie_User » Sat Apr 29, 2017 2:55 pm

Well I don't know about that. Good as Sugar was - he has my lifetime homage for our old house's VCR 4700 alone - he didn't have the mind of a technician. He knew what to build up and sell and had that canny sense to the point of genius, so I suspect he would have had the instinct to not even commission the Elk at all.


Image
That design is the 1980s wrent physical.

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Re: Should the Elk have been a 'full' Beeb?

Postby 1024MAK » Sat Apr 29, 2017 3:46 pm

Elminster wrote:The only person in the 80s who seemed to have a crystal ball was Alan Sugar, he seemed to managed to always get it right (or righter than anyone else), you have to wonder what the scene would have looked like if he had got in a couple of years earlier.

Sometimes he got it right. Amstrads range of VCR machines sold well. The original CPC464 and CPC6128 were very successful. He bought Sinclair's ZX Spectrum range and updated it. They also sold well. The original PCW range and his IBM compatible PC range (the PC1512 and the follow ups) all sold very well. The Sinclair branded home PC (the Sinclair PC200) did not sell that well.
The CPC plus range was not very successful. The Amstrad GX4000 video game console bombed. Other failures were
the Amstrad Mega PC and the PenPad (a PDA).
Expansion into the set top box market was successful, with many homes having Sky satellite decoder boxes.
The E-mailer (E-m@iler) was not a runaway success.

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Re: Should the Elk have been a 'full' Beeb?

Postby 1024MAK » Sat Apr 29, 2017 4:35 pm

Interesting, Viglen was bought by Amstrad. And it's still trading. See Wikipedia's page.

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Re: Should the Elk have been a 'full' Beeb?

Postby Elminster » Sat Apr 29, 2017 6:32 pm

1024MAK wrote:Interesting, Viglen was bought by Amstrad. And it's still trading. See Wikipedia's page.

Mark


Yep, he was canny at making money. Not everything did well but he didn't end up in the mess that all the other 8bit/16bit manufacturers did. Sometimes making money even resulted in a decent machine.

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Re: Elk: surely Mode 7 could have been software simulated in monocolour?

Postby B3_B3_B3 » Sat Apr 29, 2017 8:31 pm

Richard Russell wrote:Please no! I can't remember a more frustrating and pointless thread than this one. I've had enough of being told that the BBC and Acorn (and by association I) did such a poor job back in the early 1980s.
Richard.

I just enjoy wondering why some things were done etc , on a retro thread.

As mentioned earlier my bbc was useful to me for much longer than its competitors. :)

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Re: Should the Elk have been a 'full' Beeb?

Postby B3_B3_B3 » Sat Apr 29, 2017 8:39 pm

1024MAK wrote:One thing to add: a cut down BBC with extremely limited on-board expansion and so a PCB half the size. Say a 32k model A equivalent as far as software is conserved (see below) called a A+. And a less powerful and less expensive power supply. It could have been able to have been brought to market a lot quicker than designing a new computer like the Electron.....

paulb wrote:The problem is that as soon as you start cost-optimising the Beeb, you start to reproduce something like the Electron.

Surely the point of all the above suggestions was to gain a lower cost entry to BBC BASIC
(selling point due to school use*) while avoiding the ULA complication which lead to the electron missing it deadline. By simply using a subset of BBC B parts, the possibility of a very complex ULA missing a deadline is avoided, the design is quicker and the Acorn tech persons, having provided a more affordable entry for the masses, can sooner return to newer tech...

*So that children could work on a more affordable compatible-enough machine at home (and transfer cassette files if desired). All the other BBC B 'goody' bits were just extra cost making a bigger more expensive pcb. My ADC port was underused, its serial port, never used, 1 Mhz bus never used, RGB monitor/composite monitor ports: never used....
But they add to the cost of the machine.
paulb wrote:The Atom case would have been a reasonable choice.... You also suggested making the keyboard technology cheaper,

I only suggested cheaper by way of fewer keys: but still proper moving keys (I don't know if the Electrons keys actually worked switches or an underlying membrane like the compact which was still supposed to be OK).

paulb wrote:You do realise that probably the principal cost optimisation involved, maybe apart from the increased integration and board size reduction, was the choice of cheaper RAM? While Acorn were always miserly with RAM, there was a justification for going with cheaper RAM, just as the Spectrum had done.

I am suggesting it might have not been worth it as it made the electron dependant on a new complicated ULA which was then late.... Also, how much extra would be unacceptable, especially if 8 bit RAM meant 64K?

Why fit monitor outputs and sockets to a computer most of which will only be attached to a TV: why bring RGB lines out on an edge connector and spend money saved from fitting those components on more RAM.

paulb wrote:I think you mentioned that games only ever write to the screen in the flyback period, which is really not the case because there's not enough bandwidth.

OK, but you could just use the Spectrum style, force CPU to wait if CPU accesses video RAM area at same time as processor (other RAM full speed). I know 48K Spectrum games tend to avoid using the 16K holding the (smaller than that) graphics RAM for speed critical code because the Speccy ULA has priority in that bit. That would half the RAM bandwidth required compared to a BBC assuming 8 bit memory. But of course is now different hardware.

B3_B3_B3 wrote:For sound, either full beeb compatibility (preferred) or go for cheapness, even if only a 1 bit beeper, as other features more important in a computer whose main feature is BBC BASIC, compatible graphic modes...

paulb wrote:At some point, why bother doing an Electron at all? By the time you've pruned away ....

Because you have provided a computer with BBC BASIC and cassette compatibility and enough graphics compatibilty for BBC B schoolwork to be worked on at home. Games are a bonus (but not the unique selling point): Spectrum level games performance should be OK. And the price for that should be as cheap as possible whilst being profitable rather than the fixed target of 149 (except that the Electron was eventually launched at 199: Perhaps a target of what can we build for 149 to 249 would have been better?).

Steve Furber stated he preferred to design to a specification while being cost effective rather than to a fixed price.

paulb wrote:The end of this particular decision-making route is to just not bother with the home market .....

I think this includes some misunderstandings hopefully clarified above.
I think a cheaper machine was useful: but that it competing directly with the Spectrum on price was a mistake: BBC BASIC etc was a unique selling point, so a price premium for that was reasonable as long as still in 'perceived affordable' range of Spectrum,,,, ie I'll just save a bit more because thats worth it etc

NB I did earlier wonder if Acorn could have just avoided entering the low cost jungle by releasing a BBC BASIC cartridge(with cassette interface) for low cost computers, a similar idea to the atom BBC BASIC board... :)

Anyway, I don't seem to be going to find much more out now :)

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Re: Should the Elk have been a 'full' Beeb?

Postby paulb » Sat Apr 29, 2017 10:03 pm

B3_B3_B3 wrote:
1024MAK wrote:One thing to add: a cut down BBC with extremely limited on-board expansion and so a PCB half the size. Say a 32k model A equivalent as far as software is conserved (see below) called a A+. And a less powerful and less expensive power supply. It could have been able to have been brought to market a lot quicker than designing a new computer like the Electron.....

paulb wrote:The problem is that as soon as you start cost-optimising the Beeb, you start to reproduce something like the Electron.

Surely the point of all the above suggestions was to gain a lower cost entry to BBC BASIC
(selling point due to school use*) while avoiding the ULA complication which lead to the electron missing it deadline. By simply using a subset of BBC B parts, the possibility of a very complex ULA missing a deadline is avoided, the design is quicker and the Acorn tech persons, having provided a more affordable entry for the masses, can sooner return to newer tech...


It sounds like a great plan, so why didn't they do it? The Model A already had lots of things "deleted" for reinstatement at extra cost and still had only 16K RAM, so what you're suggesting is that they should have simplified the design but added more RAM. But had the (projected) cost of the RAM been dominant, they wouldn't have saved a great deal in cost.

(Note that I don't disagree that the Electron ULA was a problem and maybe they even anticipated it as being a potential problem, given that there are ULAs in the Beeb as well, but they could have offloaded some functionality and reduced the risk. I previously suggested them offloading the cassette functionality because it is clearly done by other means in other computers, although I haven't studied their designs. I think you interpreted that as meaning that I didn't think the Electron should have had cassette I/O, which isn't what I meant.)

B3_B3_B3 wrote:*So that children could work on a more affordable compatible-enough machine at home (and transfer cassette files if desired). All the other BBC B 'goody' bits were just extra cost making a bigger more expensive pcb. My ADC port was underused, its serial port, never used, 1 Mhz bus never used, RGB monitor/composite monitor ports: never used....
But they add to the cost of the machine.


Well, the Beeb had what it had, and the Electron didn't provide ADC, serial, 1MHz bus ports as standard, so they were already economising. I imagine that Acorn perhaps envisaged the Electron for use in other areas and thus kept the other display ports. They added cost, but probably minimal cost compared to the computing functionality.

B3_B3_B3 wrote:
paulb wrote:The Atom case would have been a reasonable choice.... You also suggested making the keyboard technology cheaper,

I only suggested cheaper by way of fewer keys: but still proper moving keys (I don't know if the Electrons keys actually worked switches or an underlying membrane like the compact which was still supposed to be OK).


OK. I interpreted use of a membrane as something like that used by the Spectrum, but I imagine that Acorn didn't want to mess around too much with a fairly successful formula. Reducing the keyboard layout was something that was actually advocated for what eventually emerged as the A3000, to take another example, but that still had a numeric keypad in the end. For the Electron, probably the biggest concern would have been the size of the thing. Indeed, the launch coverage seemed to dwell on the non-intimidating size of the machine (being the size of a tissue box).

B3_B3_B3 wrote:
paulb wrote:You do realise that probably the principal cost optimisation involved, maybe apart from the increased integration and board size reduction, was the choice of cheaper RAM? While Acorn were always miserly with RAM, there was a justification for going with cheaper RAM, just as the Spectrum had done.

I am suggesting it might have not been worth it as it made the electron dependant on a new complicated ULA which was then late.... Also, how much extra would be unacceptable, especially if 8 bit RAM meant 64K?


The problem is that they were aiming at what would have been a reasonable price window in 1983, being £150 or so with 32K RAM. Using the Beeb's architecture and more expensive RAM might have pushed the price up to £250, maybe even more. Also, it would have competed with the Model B for many people's money, yet Acorn had to sell that at £400 to have a decent margin. This might have caused an excess of Model B units instead of the excess of Electron units that actually occurred.

B3_B3_B3 wrote:Why fit monitor outputs and sockets to a computer most of which will only be attached to a TV: why bring RGB lines out on an edge connector and spend money saved from fitting those components on more RAM.


You mean why not bring them out on an edge connector? It's a good point, but I still think it's not a significant cost optimisation: a socket and three resistors, maybe a couple of other things for the RGB port.

B3_B3_B3 wrote:
paulb wrote:I think you mentioned that games only ever write to the screen in the flyback period, which is really not the case because there's not enough bandwidth.

OK, but you could just use the Spectrum style, force CPU to wait if CPU accesses video RAM area at same time as processor (other RAM full speed). I know 48K Spectrum games tend to avoid using the 16K holding the (smaller than that) graphics RAM for speed critical code because the Speccy ULA has priority in that bit. That would half the RAM bandwidth required compared to a BBC assuming 8 bit memory. But of course is now different hardware.


Well, everyone criticised the Electron's speed relative to the Beeb, so we could instead consider the speed compared to the Electron. Giving the ULA (or whatever) full access to the RAM during visible display areas is exactly what happens in modes 0 to 3. I think you may have mentioned having exclusive CPU-accessible RAM for zero page and lower memory, and this is exactly what the turbo upgrade does. Acorn were apparently aware of this, but maybe too late to incorporate it into the Electron's design.

Making every mode as slow as modes 0 to 3 wouldn't have been very popular, but if running BASIC programs is all that matters, I guess it would have been sufficient for those who would prioritise this activity. It's a bit frustrating to have your BASIC programs run a lot slower, though.

B3_B3_B3 wrote:For sound, either full beeb compatibility (preferred) or go for cheapness, even if only a 1 bit beeper, as other features more important in a computer whose main feature is BBC BASIC, compatible graphic modes...
paulb wrote:At some point, why bother doing an Electron at all? By the time you've pruned away ....

Because you have provided a computer with BBC BASIC and cassette compatibility and enough graphics compatibilty for BBC B schoolwork to be worked on at home. Games are a bonus (but not the unique selling point): Spectrum level games performance should be OK. And the price for that should be as cheap as possible whilst being profitable rather than the fixed target of 149 (except that the Electron was eventually launched at 199: Perhaps a target of what can we build for 149 to 249 would have been better?).

Steve Furber stated he preferred to design to a specification while being cost effective rather than to a fixed price.


The problem is that merely delivering a BBC BASIC experience with somewhat similar graphics was not the only factor. There was Clive Sinclair claiming that his ever-cheaper product delivered a good-enough BASIC experience. Commodore was introducing a machine with twice the RAM that would probably halve in price over the coming two or three years. And home users also wanted to do more than write BASIC, as we all acknowledge with varying degrees of guilt.

Things like beepers don't appeal to those also wanting nice games or to be able to play music. There were things like MSX which actually emphasised features like audio prominently and would have been of serious concern to UK and US manufacturers. I really don't think that slimming down the features was ever going to be a viable path.

B3_B3_B3 wrote:
paulb wrote:The end of this particular decision-making route is to just not bother with the home market .....

I think this includes some misunderstandings hopefully clarified above.
I think a cheaper machine was useful: but that it competing directly with the Spectrum on price was a mistake: BBC BASIC etc was a unique selling point, so a price premium for that was reasonable as long as still in 'perceived affordable' range of Spectrum,,,, ie I'll just save a bit more because thats worth it etc


BBC BASIC was maybe a unique selling point against the Spectrum and C64 but then the Amstrad CPC range arrived. Amstrad effectively iterated on the Beeb, right down to adopting very similar elements of the hardware and software design, and then brought production advantages to bear against the competition as well. Alan Sugar and company effectively learned and applied most of the lessons that were dished out in the first few years of the 1980s.

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Re: Elk: surely Mode 7 could have been software simulated in monocolour?

Postby Commie_User » Sat Apr 29, 2017 10:12 pm

B3_B3_B3 wrote:
Richard Russell wrote:Please no! I can't remember a more frustrating and pointless thread than this one. I've had enough of being told that the BBC and Acorn (and by association I) did such a poor job back in the early 1980s.
Richard.

I just enjoy wondering why some things were done etc , on a retro thread.

As mentioned earlier my bbc was useful to me for much longer than its competitors. :)


That's the nature of the Internet. To whatever extent, we like to give something a kick, see what falls off, then criticise it. I've been chewed a bit here for thinking programming in schools ought to remain as niche as it is, so we all have a nibble.

They didn't do a bad job in production, more they all worked to their briefs - or tried to set standards which may or may not have stuck. Trying to get Rolls-Royce experiences from Minis and Austins will always be weightless conjecture 35 years on, anyway.

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Re: Should the Elk have been a 'full' Beeb?

Postby Commie_User » Sat Apr 29, 2017 10:39 pm

paulb wrote:And home users also wanted to do more than write BASIC, as we all acknowledge with varying degrees of guilt.


There's a nub. I think as an invading Commie/Atarian here, I ran aground against the more academic nature of BBC users. The likes of myself and Speckies were in it mostly for the games - and games presented damn well, which meant bought on tape as opposed to typing in and learning too much. So a BBC aimed at us would always have been an itchy fit.

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Re: Should the Elk have been a 'full' Beeb?

Postby B3_B3_B3 » Sun Apr 30, 2017 1:41 pm

paulb wrote:It sounds like a great plan, so why didn't they do it? The Model A already had lots of things "deleted" for reinstatement at extra cost and still had only 16K RAM, so what you're suggesting is that they should have simplified the design but added more RAM. But had the (projected) cost of the RAM been dominant, they wouldn't have saved a great deal in cost.

But using a smaller PCB, cheaper case, dropping teletext, cheaper PSU etc would have saved money.
But checking my March 1983 1st issue of Micro User: Mike Cook reckoned 16K of beeb 4816 RAM chips was 2.80*8=22.4pounds or less to a single consumer. So even if four 4bit by 1 RAM chips were free to Acorn, 32K of beeb style ram would have been rather less than 45 pounds extra to Acorn.

paulb wrote:The problem is that they were aiming at what would have been a reasonable price window in 1983, being £150 or so with 32K RAM. Using the Beeb's architecture and more expensive RAM might have pushed the price up to £250, maybe even more. Also, it would have competed with the Model B for many people's money, yet Acorn had to sell that at £400 to have a decent margin. This might have caused an excess of Model B units instead of the excess of Electron units that actually occurred.

I would expect £250 to be the absolute upper limit: at 399 for a full B not a worthwhile project above that. But does it matter how much of which they sell as long as they make enough profit.
(A non beeb badged model means no license fee to Beeb so more profit for Acorn...)
paulb wrote:You mean why not bring them out on an edge connector? It's a good point, but I still think it's not a significant cost optimisation: a socket and three resistors, maybe a couple of other things for the RGB port.

I thought proper DIN/phono etc connectors/switches etc can actually be rather expensive compared to ICs etc, and if fitted by hand, again extra unwanted production expense. I also thought at the lower cost level, every saving on a non-essential feature must be grabbed. Also, I was also including the saving in fitted the composite phono connector and components. I thought the complication of 4 bit RAM worth avoiding so would trade them against those upmarket connectors.....whllst leaving the option of RGB via an edge connector.

paulb wrote:Well, everyone criticised the Electron's speed relative to the Beeb, so we could instead consider the speed compared to the Electron. Giving the ULA (or whatever) full access to the RAM during visible display areas is exactly what happens in modes 0 to 3. I think you may have mentioned having exclusive CPU-accessible RAM for zero page and lower (non graphics) memory,....

Yes, I did: as the Electron was already slow(er), I didn't think it would matter if it was differently slow :) I thought a lot of Electron games still used Mode 2. The gamers friend the C64 is only a 1Mhz 6502...so a 2Mhz one with some contention on 8 bit video RAM access would run at 2Mhz except when accessing video RAM when would be approx ((64-20)/64))*2= 0.75Mhz for a bit?
I was also presuming using 8bit wide Ram would help cancel out the slowing effect.
Halving the bandwidth meaning slower RAM is suitable might offset the 8bit vs 4bit RAM cost a bit.

NB on graphics during flyback the Speccy side scroller, Cobra, got smooth 1 pixel scrolling by copying, during flyback, an entire section of new screen from a copy 'of one It prepared earlier' but had to use the most efficient instructions: which turned out to be using the stack pointer :shock: Of course the Speccys much smaller Video RAM probably helped: so probably irrelevent to this thread :) .
http://www.retrovideogamer.co.uk/index.php?option=com_content&view=article&id=268:cobraspeccy&catid=109&Itemid=319
https://sites.google.com/site/kevinphair/home/jonathan-smith---a-tribute/frobush/Cobra/5-thescroller

paulb wrote: I think you interpreted that as meaning that I didn't think the Electron should have had cassette I/O, which isn't what I meant.)

Thats what it looked like although sounding strange (cartridges only?): if the ULA didn't do cassette presumably a collection of standard ICs or a microcontroller would be needed?
~~~~~~~

Lastly, If BBC BASIC/environment wasn't a unique enough selling point for a low cost Acorn computer: then the Electron looks a bit of a dubious venture, although, I still think a lower cost 32K(or more :) ) entry than a BBC B was useful, hence my wonderings about BBC_BASIC-cartridges (with BBC cassette interfaces) for other computers etc etc. Perhaps avoiding the Electron but making a much earlier IP-correct but cost optimised B+/Proton+ pair would have been better (Proton+ taking the place of the A: minus some BBC required components and badge hence no license fee?) . NB I would have preferred the Master to be more of a superset of such a B+, rather than being less compatible.

Did the BBC itself own BBC BASIC? I wonder if Amstrad CPC464 (or other machine) could have just made Locomotive(or whatever) BASIC rom very BBC BASIC compatible with no fall out from Acorn? BBC cassette compatibility is presumably legally easy. If other manufacturers, had installed BBC BASICs, and Acorn had thus avoided the Electron, might that ironically been better for them. Who knows :)

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Re: Should the Elk have been a 'full' Beeb?

Postby 1024MAK » Sun Apr 30, 2017 2:40 pm

The Sinclair Cambridge Computer Z88 notebook used the Z80 version of BBC BASIC. As did the Amstrad NC100 and NC200 notebooks.

Mark
For a "Complete BBC Games Archive" visit www.bbcmicro.co.uk NOW!
BeebWiki‬ - for answers to many questions...

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Re: Should the Elk have been a 'full' Beeb?

Postby paulb » Sun Apr 30, 2017 3:38 pm

B3_B3_B3 wrote:
paulb wrote:It sounds like a great plan, so why didn't they do it? The Model A already had lots of things "deleted" for reinstatement at extra cost and still had only 16K RAM, so what you're suggesting is that they should have simplified the design but added more RAM. But had the (projected) cost of the RAM been dominant, they wouldn't have saved a great deal in cost.

But using a smaller PCB, cheaper case, dropping teletext, cheaper PSU etc would have saved money.
But checking my March 1983 1st issue of Micro User: Mike Cook reckoned 16K of beeb 4816 RAM chips was 2.80*8=22.4pounds or less to a single consumer. So even if four 4bit by 1 RAM chips were free to Acorn, 32K of beeb style ram would have been rather less than 45 pounds extra to Acorn.


That's in this article:

When these memory chips were first introduced they cost £25 each. Today, do not pay more than £3 for them.

Unfortunately you will need eight of them, but if you have three friends it will be worth your while sending off for them together as you can get a price reduction: £2.80 off 8 ICs is typical for quantities over 25 and even more in 100-off quantities.


So, the £2.80 figure actually sounds like the discount, but it's also in the price range he initially mentioned. Eight of these supposedly provide 16K, so as you say, 32K would have been £45 at that time. One issue is whether anyone expected the price to be this low by then. Remember that companies were hoarding dynamic RAM due to a shortage that eventually turned into a glut.

Using 4816 ICs certainly would have given better performance, and if you gave the ULA complete access to the memory when it needed it, just offering 2MHz access to RAM in the other periods would have virtually made up for abandoning those cycles that the Electron does use in modes 4 to 6 between the ULA's accesses:

Code: Select all

256 lines with 48 access cycles, 56 lines with 128 access cycles, 2MHz RAM access: 19456 bytes
312 lines with 64 access cycles, 1MHz RAM access: 19968 bytes


In modes 0 to 3, the performance would, of course, be better:

Code: Select all

256 lines with 48 access cycles, 56 lines with 128 access cycles, 2MHz RAM access: 19456 bytes (again)
256 lines with 24 access cycles, 56 lines with 64 access cycles, 1MHz RAM access: 9728 bytes


To summarise the problem, then, Acorn needed to decide whether memory was going to remain expensive and, having assumed that it would, concluded that it was economical to devise a method of using cheaper memory. Obviously, this decision needed to occur a year or two before the machine's release. There was also the matter of how many ICs would be required to provide the memory, which would have had an impact on board and product size.

B3_B3_B3 wrote:
paulb wrote:The problem is that they were aiming at what would have been a reasonable price window in 1983, being £150 or so with 32K RAM. Using the Beeb's architecture and more expensive RAM might have pushed the price up to £250, maybe even more. Also, it would have competed with the Model B for many people's money, yet Acorn had to sell that at £400 to have a decent margin. This might have caused an excess of Model B units instead of the excess of Electron units that actually occurred.

I would expect £250 to be the absolute upper limit: at 399 for a full B not a worthwhile project above that. But does it matter how much of which they sell as long as they make enough profit.
(A non beeb badged model means no license fee to Beeb so more profit for Acorn...)


True enough. I don't remember if there were obligations for Acorn such as sales targets (must ship a certain number) or product longevity (must offer the product over an extended period of time). Or whether Acorn were not allowed to offer the same machines under their own brand, at least in the UK.

B3_B3_B3 wrote:
paulb wrote:You mean why not bring them out on an edge connector? It's a good point, but I still think it's not a significant cost optimisation: a socket and three resistors, maybe a couple of other things for the RGB port.

I thought proper DIN/phono etc connectors/switches etc can actually be rather expensive compared to ICs etc, and if fitted by hand, again extra unwanted production expense. I also thought at the lower cost level, every saving on a non-essential feature must be grabbed. Also, I was also including the saving in fitted the composite phono connector and components. I thought the complication of 4 bit RAM worth avoiding so would trade them against those upmarket connectors.....whllst leaving the option of RGB via an edge connector.


I really don't know what costs the connectors incur in terms of component pricing and assembly complexity. I rather think that some buyers might have traded the RGB and composite ports for, say, joystick ports, but I suspect that two ports (cassette and UHF) plus edge connector would have made the machine look too frugal and potentially unappealing to people with no clear idea of what they would use their computer for. Which was most people.

B3_B3_B3 wrote:Yes, I did: as the Electron was already slow(er), I didn't think it would matter if it was differently slow :) I thought a lot of Electron games still used Mode 2.


Did you have an Electron or a Beeb? It became very predictable, especially later in the 1980s, that Electron games would be mode 5 affairs, or mode 4 for ones which needed more resolution. An interesting example is Palace of Magic, which followed on from Citadel - a mode 2 game - but which ran in mode 5. It is also interesting that someone did a remake for the Electron in mode 2, and it is impressive, but I would argue that this builds on a lot of the knowledge about optimisation that was unlikely to be applied in rushing to get a game converted and released in the 1980s. In general, people converting games would realise that mode 2 would be too slow on the Electron and did the easiest thing to get their job done.

B3_B3_B3 wrote:The gamers friend the C64 is only a 1Mhz 6502...so a 2Mhz one with some contention on 8 bit video RAM access would run at 2Mhz except when accessing video RAM when would be approx ((64-20)/64))*2= 0.75Mhz for a bit?
I was also presuming using 8bit wide Ram would help cancel out the slowing effect.
Halving the bandwidth meaning slower RAM is suitable might offset the 8bit vs 4bit RAM cost a bit.


Yes, as noted above, if you just use 2MHz-capable RAM instead of 4MHz-capable (100ns) RAM, the cost of 4816 RAM might have been less. For 1MHz access the Electron's TM4164EC4-15 parts have row access times of 150ns and column access times of 90ns. (Of course, the C64 had extra graphics hardware, and games probably steered away from operations that would have been necessary on the Acorn machines.)

B3_B3_B3 wrote:Lastly, If BBC BASIC/environment wasn't a unique enough selling point for a low cost Acorn computer: then the Electron looks a bit of a dubious venture, although, I still think a lower cost 32K(or more :) ) entry than a BBC B was useful, hence my wonderings about BBC_BASIC-cartridges (with BBC cassette interfaces) for other computers etc etc. Perhaps avoiding the Electron but making a much earlier IP-correct but cost optimised B+/Proton+ pair would have been better (Proton+ taking the place of the A: minus some BBC required components and badge hence no license fee?) . NB I would have preferred the Master to be more of a superset of such a B+, rather than being less compatible.


I think contractual obligations complicate what Acorn might have done with the Proton. As for the Electron, apart from trying to force Sinclair out of the market, it's possible that the principal motivation was a cheaper version of the "school computer". But with the compromises made and with the broader public looking for versatility in justifying their purchase (kids want games, adults want serious things, but the kids usually get their way), one wonders whether Acorn wouldn't have been better off selling the Electron in some form into schools so that they would get more for their money. But again, that might have upset some important people.

B3_B3_B3 wrote:Did the BBC itself own BBC BASIC? I wonder if Amstrad CPC464 (or other machine) could have just made Locomotive(or whatever) BASIC rom very BBC BASIC compatible with no fall out from Acorn? BBC cassette compatibility is presumably legally easy. If other manufacturers, had installed BBC BASICs, and Acorn had thus avoided the Electron, might that ironically been better for them. Who knows :)


Other people can talk about BBC BASIC. The cassette I/O was an informal standard already.

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Re: Should the Elk have been a 'full' Beeb?

Postby B3_B3_B3 » Sun Apr 30, 2017 7:00 pm

paul b wrote:'I thought a lot of Electron games still used Mode 2.'
Did you have an Electron or a Beeb? It became very predictable, especially later in the 1980s, that Electron games would be mode 5 affairs, or mode 4 for ones which needed more resolution. ....but...

Yes, I did have a beeb: I must remember wrong :oops: perhaps mislead by the few (eg Snapper) that did or perhaps the adverts showed beeb version then said also for electron or I just remember wrong...

If most games ran in mode 4 or 5, perhaps all the ULA trouble/delay could have been avoided by only supporting modes 4,5,(6).... Poor Acorn :(

No more questions [edit]left from me on this subject[/edit] :)
Last edited by B3_B3_B3 on Sun Apr 30, 2017 10:40 pm, edited 3 times in total.

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Re: Should the Elk have been a 'full' Beeb?

Postby paulb » Sun Apr 30, 2017 7:54 pm

B3_B3_B3 wrote:Yes, I did have a beeb: I must remember wrong :oops: perhaps mislead by the few (eg Snapper) that did or perhaps the adverts showed beeb version then said also for electron or I just remember wrong...


Like when Electron User would just print the Beeb review from the Micro User and do a search-and-replace. I guess they didn't think that Electron owners might actually know Beeb owners.

B3_B3_B3 wrote:If most games ran in mode 4 or 5, perhaps all the ULA trouble/delay could have been avoided by only supporting modes 4,5,(6).... Poor Acorn :(


Well, games were still possible in mode 2. Magic Mushrooms is an example of a nice mode 2 game that seems to be the mostly the same on the Electron as on the Beeb.

B3_B3_B3 wrote:No more questions :)


Well, it's been a good discussion, but I don't see any reason why people shouldn't analyse the sequence of events that led to certain things being done in a certain way. You've probably seen them already, but here is one of many articles reviewing the history through adverts of the time.

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Re: Should the Elk have been a 'full' Beeb?

Postby Coeus » Sun Apr 30, 2017 9:03 pm

B3_B3_B3 wrote:...or perhaps the adverts showed beeb version then said also for electron or I just remember wrong...


Probably there would be a note somewhere in 4pt type. A bit like the TV adverts for games, even now, where there is a message along the bottom say "not actual game footage". Why not? Presumably because a movie studio rendering farm can produce better output than the game can, so it is a deliberate attempt to make customers think it is better than it is, despite the disclaimer.

You have to assume advertisers are out to trick you. "80% of women said the product did X (sample size 130)" = oh yes, run an independent trial, wih proper random selection and enough participants for a meaningful result and I'll believe you. "Nothing works faster!" or in other words "There are other products that work just as fast, but they cost less because then you're not paying for this advertising".


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