A cassette recorder would've been great and a plug to bung on the end of the power supply - even if the plug was handed to you as you bought it or wired on by the instore technician and tested.
I think these days a plug is already fitted to everything (EU regulations?) but I do appreciate what you mean about one being in "the box" if nothing else if it was a UK model there would be little doubt about its type, I do not think those three pin "round" sockets were still in use back then ?
Its funny tape players were mentioned as I was actually thinking about that the other day when looking at a few. Given that Acorn and CBM machines had one it would of been sensible to have a Sinclair branded one as an optional extra. I actually had one of the Acorn ones for my Speccy in the early 90's as Greenweld Electronics (IIRC) were selling new old stock ones cheaply, it worked fine with a suitable lead.
! Standby alert !
“There are four lights!”
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb!
Looking forward to summer in Somerset later in the year :)
The Acorn ones were just badged normal "computer" tape decks.
Mark
Yes I recall seeing a Silver one I cannot remember the brand. They appeared to be reasonably well constructed though and had the PSU transformer inside the main case rather than a 'brick'
Should it have come with a different CPU?
Given that a lot of Commodore fans bang on about the 6502 being, clock for clock faster than Zilogs wee beastie would a 6502 powered Speccy be faster than a Z80 powered one or is the Speccy design fixed around the Zilog chip?
I ask in all ignorance not being all that techy minded where CPUs are concerned.
Should it have come with a different CPU?
Given that a lot of Commodore fans bang on about the 6502 being, clock for clock faster than Zilogs wee beastie would a 6502 powered Speccy be faster than a Z80 powered one or is the Speccy design fixed around the Zilog chip?
I ask in all ignorance not being all that techy minded where CPUs are concerned.
The 6502 was a cheap version of the Motorola 6800 - it was a much simpler chip than the Z80. It had (I recall) one accumulator and two index registers, and a weaker instruction set. The Z80 had 8- and 16-bit registers and a better (if arcane) instruction set, with things like LDIR (although savvy programmers used a POP routine to push graphics around even faster).
In terms of speed, I think that the 6502 could handle more instructions per clock cycle, and access to memory and video could really steal clock cycles from the Z80 - you ended up getting wait states that caused on-screen flicker, unless the programmer knew their t-states intimately (I'm looking at you, Simon Brattel).
But the Z80 had better stack handling. The 6502 had a fixed 256 byte stack, whilst the Z80 had a 16-bit stack pointer that could be set anywhere in the address space.
I actually think the Z80 was used in the Game Boy and the Megadrive! So it was a capable chip.
Been waiting for someone to say her, Sam Fox or some other lady from the Sun.
Well, there was Maria Whittaker, Sam Fox, Corinne Russell from the Vixen poster, and whoever was on the Psycho Pigs UXB ad. But then there was that snap with a C5 in the back page of Sinclair User (an old edition, think it had a pirate on the front). Jo Guest, perhaps? I think that was probably my first 'exposure' to such material too, the filthy lot...
Commodore fans often just compare different CPUs at the same clock speed, without considering how those clock signals are used inside the CPU. The 6502 uses the edges of the clocks for timing, while the Z80 divides the external clock signal down to provide a "state machine" system, hence why with the Z80 memory cycles are not the same as machine cycles.
But overall, the throughput of each of these CPUs at the manufacturers recommended CPU frequency, is more or less the same for general purpose computing. Of course, in some specific areas, one is slightly stronger that the other, but this goes both ways.
One slight advantage that the Z80 has over the 6502, is that due to the greater number of Z80 instructions and hence operations, code doing the same job can sometimes take up less memory space.
But the memory bus arrangement of the 6502 means it is easier to interface to a memory mapped display without memory contention.
It was easier to use DRAM with a Z80, due to this CPUs built in DRAM refresh circuits.
This list could go on and on and on, but I think you get the picture. They are different, but neither is significantly better than the other.
If anything, possibly the best 8 bit CPU is the 6809. But it only made it into a relatively small number of models of home computers. However, I have not played with this CPU so I am only going on the paper specs... so could be wrong...
! Standby alert !
“There are four lights!”
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb!
Looking forward to summer in Somerset later in the year :)
Many thanks for the clear explanations guys regarding CPUs,very grateful. :)
I don't quite agree with some of the above. The 6502 is clearly slower than either the z80 or 6809.
Superficial discussion in favour of the 6502 or 6809 centers around fewer clock cycles per instruction. This also means the clock period has to be extended to accommodate the slowest one-cycle operation on the chip, making instructions slower in comparison to one that breaks an operation into several shorter cycles.
The faster clock of the z80 is not done just for the sake of it, it made interfacing to the rest of the circuit easier. Zilog was able to put dram refresh onto the chip and sophisticated interrupt modes which fit into the external bus cycles. This tended to make the system cost of z80 machines lower. It also had one very important result: the chip speed was more decoupled from ram speed. The gap between 6502/6809 clock speed and z80 clock speed increased with years because ram speed increased more slowly than logic speed. So you ended up with z80s being clocked initially 2x faster then that grew to 3x faster and higher than 6502/6809 contemporaries over time. So in the marketplace, z80 relative performance rose in comparison to these other chips. This is why the z80 was so dominant in the 8-bit market, perhaps by a couple of orders of magnitude until the 68xx saw a rebirth in the HC11 microcontroller line.
The coupling with ram speed aside, when comparing speed you have to compare chips made at the same technology level. This is because you can always make a chip faster simply by shrinking it. The amount of shrink possible depends on the current manufacturing technology. So a z80 made in 1976 was 4MHz but a z80 made in 1978(?) could be 6MHz, for example. For the z80/6502/6809 the same feature size means for comparison purposes the z80 should be clocked twice as high as the 6502/6809. To do any comparison of value you have to do benchmarks, that is writing real subroutines or programs using the same algorithms and then comparing things like speed and space occupation.
I would agree with a previous post that 6502 code size is larger than the z80 and the 6809 may be smaller than the z80.
In terms of cost, in the earlier days the z80 and 68xx were similar in price but the 6502 caused heart attacks at its introduction because it debuted at $20 a pop versus the 68xx's price tag of $200 a pop. They could do this because the 6502 was so small and could fit more chips onto a single die. The 6502 was a cut down 68xx so this directly threatened Motorola who tried to stop the 6502 from being made by claiming it infringed on its IP. This didn't work, except I think MOS had to change the assembly mnemonics to be more different from the 68xx (I think that's right?)
Anyway the reason why the 6502 saw so much adoption in home computers was this price differential. It allowed companies like Atari and Commodore to spend more money on other specialized chips for graphics and sound.
In terms of the Sinclair line, the z80 was essential for the zx80 and zx81 because their design required special features of the z80 to get the z80 to generate the video display on the cheap. No other 8-bit cpu could have been substituted. Along came the spectrum and it needed a z80 because the basic rom was mainly lifted from the zx81; a change would have meant rewriting the system software. I'm sure the difference in price between the 6502 and z80 would have been much less dramatic by the time the 80s rolled around so maybe the cost incentive to use a 6502 in a new design wouldn't have been so strong.
The 6809 is a nice chip, a bit of a latecomer, but I don't think it's as fast as 6809 aficionados like to think :) Certainly it couldn't keep up in speed in later years with the z80 because of the ram speed thing.
BTW, if it counts, the most sophisticated 8-bit cpu made was probably the z280, which was the z80 successor, and was delayed / nearly cancelled by zilog as they concentrated on their 16 and 32 bit cpus. It came out in the mid 80s and was a flop maybe because it was too sophisticated for an 8-bit. It had caches, mmu, dma controllers, etc. It is not 16-bit as its wikipedia page claims nor as its own datasheet claims :P The register set consists of the same 8-bit registers A through L and 16-bits are formed the same way by pairing.
Ok so for the purpose of this interesting discussion, I would say that if I was in charge of Sinclair at the time (and armed with hindsight) then I would have made these changes:
- All additional changes to the Spectrum would be implemented on a Spectrum+ model but the difference is that I would release this in parallel to the rubber keyed model as a premium top-end product in 1982. The 48K model was such a success because of its aggressive price point and so no changes could be made without this altering its market advantage.
I would also discontinue R&D on ZX Microdrive, QL and Interface I and II.
The QL was a hamstrung 16-bit system with no support, no backwards compatibility or standard business peripherals or interconnects. The Microdrive add-on was a waste of time and had taken most of 1983 to produce. Everything after the original Spectrum was a waste of resources (Except for the 128K model, but this was too little and too late). I personally wouldn't have released the ZX Microdrive, ZX Interface I/Interface II, QL, 16K Spectrum or the C5. If I could make a decision with hindsight then my immediate plan after the original ZX Spectrum would have been the release of the Spectrum+ model in 1982 side-by-side with the 48K model and I would have added these features for around £250 (to be in-line with the C64):
- Sold in two versions; one with a built-in datacorder like the +2, and one without like the 128K+
- Full QL QWERTY keyboard with function keys
- Power and reset buttons as previously suggested
- 80K RAM (64K of Upper RAM available) allowing 16K for ROM functions
- RGB monitor/composite video output and RF module
- 1 x Edge connector expansion slot
- DE-9 RS-232 interface located at rear for local area networking
- Implement a ROM cartridge slot at the side of the unit that could address 64K (original design addressed up to 16K)
- 2 x SJS Sinclair Joystick ports at the side of the casing next to the cartridge slot
- 1 x Kempston joystick port at the rear for use with a mouse/atari compatible input device
- Rear mic/ear combined audio jack and higher baud rate for tape loading
- Yamaha AY-3-8912 3-channel sound generator
- X80 Floating Point Maths Co-Processor
The X80 is a floating-point unit for Z80 based computers. It is a hardware implementation of the calculator library of the ZX Spectrum ROM written by Steve Vickers. Programs written for the ZX Spectrum will automatically use the standard functions without the need for recompiling and will speed up calculations for greater performance.
The datagear allows you to move around memory very quickly using a DMA. Around 17KB a frame or 850kb a second With its function being to speed up memory transfers. This fast burst data transfer significantly increases performance for the spectrum with most operations including allowing multicolour screen modes using a Z80 DMA Z84C1008 running at 8MHz. Maximum speed of data transfer is 17.3 kB (17727 bytes) / frame = 865.6 kB (886350 bytes) / second.
- 16K video memory buffer for use with DMA to increase screen draw performance
- Support for additional Timex Sinclair TS2068 Hi-Colour 8x1 screen modes for 256x192 and 512x192 resolutions
The Timex Sinclair 2068 (TS2068), released in November 1983, was arguably one of the first Sinclair clones to significantly improve on the original design and added a number of new features including an improved ULA with additional screen modes:
Timex resolutions @ 256x192 and 512x192. 256×192 mode with a colour resolution of 32×24, 256×192 pixels with colour resolution of 32×192 Hi-Colour 8x1 attributes and monochrome 512×192 mode.
This would have been offered with various software bundles that would target education, business, entertainment and creative fields. I would also rely heavily on third party peripherals so that Sinclair wouldn't have to invest in development and production of monitors, printers, mass storage etc.
The 48K rubber key model would be discontinued by 1984.
An optional purchase of a GUI OS supplied on ROM cartridge with a mouse would also have been a priority for me and would have been based on the original Apple OS. Here is an example of an 8-bit GUI OS - http://atari8.co.uk/gui/
This wouldn't have broken the bank in terms of R&D at all compared to what the QL cost and would have addressed most of the needs and criticisms that was levied on the original rubber keyed Speccy.
As for the mass storage solution, I would have partnered up with a number of third party manufacturers to produce a series of external floppy drive solutions at an additional cost to the user as a separate purchase. Despite the initial cost at the time for a drive, it was still necessary to offer a mass storage solution in order to promote the Spectrum as a professional product like Acorn had done so with the BBC Micro.
As for the 1984 product line-up and beyond, Sinclair should have offered 4 simple product categories to work with over the years.
The technology would be consolidated and would all be 100% compatible with each other.
- Consumer Computer (Home use, Hobbyist)
- Professional Computer (Educational, Home Professional, Small to Medium Business)
- Mobile (Z88 series)
- Entertainment (Unreleased project 'Janus' Sinclair Games Console)
The new consumer Spectrum would have replaced what would have been the failed QL product and would offer (for under £400):
- All of the previous features of the Spectrum+ model explained above.
- QL style casing but omitting the microdrives for a 3.5" floppy drive (similar to Amstrad +3) with Uni-DOS MGT filesystem
- 7MHz Z80H CPU (or Z180 with MMU depending on compatibility)
- 128K base RAM up to 512K internally expandable system RAM (with the option of an additional external RAM extended module mimicking the Sam Coupe's limitation of 4.5MB) The internal and expanded RAM options would be called ZXpand Modules.
- Philips SAA1099 6-channel, 8-Octave sound generator chip (released in 1984 and used in Sam Coupe, Creative Sound/Game Blaster and Silicon Graphics workstation)
- CP/M 2.2 DOS support
- ULA+ replacement supporting up to 256 colour palette in all resolutions
- New ULA and ROMs with extended BASIC. This would be based on Andrew Owen's OpenSE BASIC and ULA+
- Industry standard 9-pin and 25-pin Serial and Parallel port connections at rear for printing and local networking
- Rear mic/ear combined audio jack for backwards software compatibility
An optional third party Office Productivity package, GUI OS on ROM cartridge, mouse, RGB monitor and printer would be sold separately and also offered for the consumer and business Spectrum models in special package deals.
The QL originally retailed for around £399 and I believe Sinclair could have produced an improved consumer Spectrum for the same price or less with those aforementioned features.
There could also have been a separate blitter board expansion that connected at the rear and would essentially be a graphics chip offering new resolutions and more colours.
Comments
I aim to please, wouldn't want to disappoint, ;)
The 128k basic could have had:
A function to be run in IF2 mode,
some sprite support
even some type of assembler?
But that would have cost a bit of money, and delayed the release,
just to please a minority.
Download the latest version of Bomb Munchies Ver2210 4th July 2020
Its funny tape players were mentioned as I was actually thinking about that the other day when looking at a few. Given that Acorn and CBM machines had one it would of been sensible to have a Sinclair branded one as an optional extra. I actually had one of the Acorn ones for my Speccy in the early 90's as Greenweld Electronics (IIRC) were selling new old stock ones cheaply, it worked fine with a suitable lead.
Mark
Repair Guides. Spanish Hardware site.
WoS - can't download? Info here...
former Meulie Spectrum Archive but no longer available :-(
Spectranet: the TNFS directory thread
! Standby alert !
“There are four lights!”
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb!
Looking forward to summer in Somerset later in the year :)
Yes I recall seeing a Silver one I cannot remember the brand. They appeared to be reasonably well constructed though and had the PSU transformer inside the main case rather than a 'brick'
Oh and if we are to get sound though the telly, none of that awful background noise the 16 and 48k models made when you put them though an amplifier.
Given that a lot of Commodore fans bang on about the 6502 being, clock for clock faster than Zilogs wee beastie would a 6502 powered Speccy be faster than a Z80 powered one or is the Speccy design fixed around the Zilog chip?
I ask in all ignorance not being all that techy minded where CPUs are concerned.
The 6502 was a cheap version of the Motorola 6800 - it was a much simpler chip than the Z80. It had (I recall) one accumulator and two index registers, and a weaker instruction set. The Z80 had 8- and 16-bit registers and a better (if arcane) instruction set, with things like LDIR (although savvy programmers used a POP routine to push graphics around even faster).
In terms of speed, I think that the 6502 could handle more instructions per clock cycle, and access to memory and video could really steal clock cycles from the Z80 - you ended up getting wait states that caused on-screen flicker, unless the programmer knew their t-states intimately (I'm looking at you, Simon Brattel).
But the Z80 had better stack handling. The 6502 had a fixed 256 byte stack, whilst the Z80 had a 16-bit stack pointer that could be set anywhere in the address space.
I actually think the Z80 was used in the Game Boy and the Megadrive! So it was a capable chip.
Speaking of which...
http://flashbak.com/yugoslavian-computer-magazine-cover-girls-of-the-1980s-90s-370271/
- IONIAN-GAMES.com -
But overall, the throughput of each of these CPUs at the manufacturers recommended CPU frequency, is more or less the same for general purpose computing. Of course, in some specific areas, one is slightly stronger that the other, but this goes both ways.
One slight advantage that the Z80 has over the 6502, is that due to the greater number of Z80 instructions and hence operations, code doing the same job can sometimes take up less memory space.
But the memory bus arrangement of the 6502 means it is easier to interface to a memory mapped display without memory contention.
It was easier to use DRAM with a Z80, due to this CPUs built in DRAM refresh circuits.
This list could go on and on and on, but I think you get the picture. They are different, but neither is significantly better than the other.
If anything, possibly the best 8 bit CPU is the 6809. But it only made it into a relatively small number of models of home computers. However, I have not played with this CPU so I am only going on the paper specs... so could be wrong...
Mark
Repair Guides. Spanish Hardware site.
WoS - can't download? Info here...
former Meulie Spectrum Archive but no longer available :-(
Spectranet: the TNFS directory thread
! Standby alert !
“There are four lights!”
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb!
Looking forward to summer in Somerset later in the year :)
The fun level depends what year the vehicle was built. :)
@1024MAK
Many thanks for the clear explanations guys(and Joefish who I thanked accidentally. :D) regarding CPUs,very grateful. :)
I don't quite agree with some of the above. The 6502 is clearly slower than either the z80 or 6809.
Superficial discussion in favour of the 6502 or 6809 centers around fewer clock cycles per instruction. This also means the clock period has to be extended to accommodate the slowest one-cycle operation on the chip, making instructions slower in comparison to one that breaks an operation into several shorter cycles.
The faster clock of the z80 is not done just for the sake of it, it made interfacing to the rest of the circuit easier. Zilog was able to put dram refresh onto the chip and sophisticated interrupt modes which fit into the external bus cycles. This tended to make the system cost of z80 machines lower. It also had one very important result: the chip speed was more decoupled from ram speed. The gap between 6502/6809 clock speed and z80 clock speed increased with years because ram speed increased more slowly than logic speed. So you ended up with z80s being clocked initially 2x faster then that grew to 3x faster and higher than 6502/6809 contemporaries over time. So in the marketplace, z80 relative performance rose in comparison to these other chips. This is why the z80 was so dominant in the 8-bit market, perhaps by a couple of orders of magnitude until the 68xx saw a rebirth in the HC11 microcontroller line.
The coupling with ram speed aside, when comparing speed you have to compare chips made at the same technology level. This is because you can always make a chip faster simply by shrinking it. The amount of shrink possible depends on the current manufacturing technology. So a z80 made in 1976 was 4MHz but a z80 made in 1978(?) could be 6MHz, for example. For the z80/6502/6809 the same feature size means for comparison purposes the z80 should be clocked twice as high as the 6502/6809. To do any comparison of value you have to do benchmarks, that is writing real subroutines or programs using the same algorithms and then comparing things like speed and space occupation.
I would agree with a previous post that 6502 code size is larger than the z80 and the 6809 may be smaller than the z80.
In terms of cost, in the earlier days the z80 and 68xx were similar in price but the 6502 caused heart attacks at its introduction because it debuted at $20 a pop versus the 68xx's price tag of $200 a pop. They could do this because the 6502 was so small and could fit more chips onto a single die. The 6502 was a cut down 68xx so this directly threatened Motorola who tried to stop the 6502 from being made by claiming it infringed on its IP. This didn't work, except I think MOS had to change the assembly mnemonics to be more different from the 68xx (I think that's right?)
Anyway the reason why the 6502 saw so much adoption in home computers was this price differential. It allowed companies like Atari and Commodore to spend more money on other specialized chips for graphics and sound.
In terms of the Sinclair line, the z80 was essential for the zx80 and zx81 because their design required special features of the z80 to get the z80 to generate the video display on the cheap. No other 8-bit cpu could have been substituted. Along came the spectrum and it needed a z80 because the basic rom was mainly lifted from the zx81; a change would have meant rewriting the system software. I'm sure the difference in price between the 6502 and z80 would have been much less dramatic by the time the 80s rolled around so maybe the cost incentive to use a 6502 in a new design wouldn't have been so strong.
The 6809 is a nice chip, a bit of a latecomer, but I don't think it's as fast as 6809 aficionados like to think :) Certainly it couldn't keep up in speed in later years with the z80 because of the ram speed thing.
BTW, if it counts, the most sophisticated 8-bit cpu made was probably the z280, which was the z80 successor, and was delayed / nearly cancelled by zilog as they concentrated on their 16 and 32 bit cpus. It came out in the mid 80s and was a flop maybe because it was too sophisticated for an 8-bit. It had caches, mmu, dma controllers, etc. It is not 16-bit as its wikipedia page claims nor as its own datasheet claims :P The register set consists of the same 8-bit registers A through L and 16-bits are formed the same way by pairing.
Write games in C using Z88DK and SP1
- All additional changes to the Spectrum would be implemented on a Spectrum+ model but the difference is that I would release this in parallel to the rubber keyed model as a premium top-end product in 1982. The 48K model was such a success because of its aggressive price point and so no changes could be made without this altering its market advantage.
I would also discontinue R&D on ZX Microdrive, QL and Interface I and II.
The QL was a hamstrung 16-bit system with no support, no backwards compatibility or standard business peripherals or interconnects. The Microdrive add-on was a waste of time and had taken most of 1983 to produce. Everything after the original Spectrum was a waste of resources (Except for the 128K model, but this was too little and too late). I personally wouldn't have released the ZX Microdrive, ZX Interface I/Interface II, QL, 16K Spectrum or the C5. If I could make a decision with hindsight then my immediate plan after the original ZX Spectrum would have been the release of the Spectrum+ model in 1982 side-by-side with the 48K model and I would have added these features for around £250 (to be in-line with the C64):
- Sold in two versions; one with a built-in datacorder like the +2, and one without like the 128K+
- Full QL QWERTY keyboard with function keys
- Power and reset buttons as previously suggested
- 80K RAM (64K of Upper RAM available) allowing 16K for ROM functions
- RGB monitor/composite video output and RF module
- 1 x Edge connector expansion slot
- DE-9 RS-232 interface located at rear for local area networking
- Implement a ROM cartridge slot at the side of the unit that could address 64K (original design addressed up to 16K)
- 2 x SJS Sinclair Joystick ports at the side of the casing next to the cartridge slot
- 1 x Kempston joystick port at the rear for use with a mouse/atari compatible input device
- Rear mic/ear combined audio jack and higher baud rate for tape loading
- Yamaha AY-3-8912 3-channel sound generator
- X80 Floating Point Maths Co-Processor
The X80 is a floating-point unit for Z80 based computers. It is a hardware implementation of the calculator library of the ZX Spectrum ROM written by Steve Vickers. Programs written for the ZX Spectrum will automatically use the standard functions without the need for recompiling and will speed up calculations for greater performance.
- Datagear DMA (Direct Memory Access) MB02 Controller Interface
The datagear allows you to move around memory very quickly using a DMA. Around 17KB a frame or 850kb a second With its function being to speed up memory transfers. This fast burst data transfer significantly increases performance for the spectrum with most operations including allowing multicolour screen modes using a Z80 DMA Z84C1008 running at 8MHz. Maximum speed of data transfer is 17.3 kB (17727 bytes) / frame = 865.6 kB (886350 bytes) / second.
- 16K video memory buffer for use with DMA to increase screen draw performance
- Support for additional Timex Sinclair TS2068 Hi-Colour 8x1 screen modes for 256x192 and 512x192 resolutions
The Timex Sinclair 2068 (TS2068), released in November 1983, was arguably one of the first Sinclair clones to significantly improve on the original design and added a number of new features including an improved ULA with additional screen modes:
Timex resolutions @ 256x192 and 512x192. 256×192 mode with a colour resolution of 32×24, 256×192 pixels with colour resolution of 32×192 Hi-Colour 8x1 attributes and monochrome 512×192 mode.
This would have been offered with various software bundles that would target education, business, entertainment and creative fields. I would also rely heavily on third party peripherals so that Sinclair wouldn't have to invest in development and production of monitors, printers, mass storage etc.
The 48K rubber key model would be discontinued by 1984.
An optional purchase of a GUI OS supplied on ROM cartridge with a mouse would also have been a priority for me and would have been based on the original Apple OS. Here is an example of an 8-bit GUI OS - http://atari8.co.uk/gui/
This wouldn't have broken the bank in terms of R&D at all compared to what the QL cost and would have addressed most of the needs and criticisms that was levied on the original rubber keyed Speccy.
As for the mass storage solution, I would have partnered up with a number of third party manufacturers to produce a series of external floppy drive solutions at an additional cost to the user as a separate purchase. Despite the initial cost at the time for a drive, it was still necessary to offer a mass storage solution in order to promote the Spectrum as a professional product like Acorn had done so with the BBC Micro.
As for the 1984 product line-up and beyond, Sinclair should have offered 4 simple product categories to work with over the years.
The technology would be consolidated and would all be 100% compatible with each other.
- Consumer Computer (Home use, Hobbyist)
- Professional Computer (Educational, Home Professional, Small to Medium Business)
- Mobile (Z88 series)
- Entertainment (Unreleased project 'Janus' Sinclair Games Console)
The new consumer Spectrum would have replaced what would have been the failed QL product and would offer (for under £400):
- All of the previous features of the Spectrum+ model explained above.
- QL style casing but omitting the microdrives for a 3.5" floppy drive (similar to Amstrad +3) with Uni-DOS MGT filesystem
- 7MHz Z80H CPU (or Z180 with MMU depending on compatibility)
- 128K base RAM up to 512K internally expandable system RAM (with the option of an additional external RAM extended module mimicking the Sam Coupe's limitation of 4.5MB) The internal and expanded RAM options would be called ZXpand Modules.
- Philips SAA1099 6-channel, 8-Octave sound generator chip (released in 1984 and used in Sam Coupe, Creative Sound/Game Blaster and Silicon Graphics workstation)
- CP/M 2.2 DOS support
- ULA+ replacement supporting up to 256 colour palette in all resolutions
- New ULA and ROMs with extended BASIC. This would be based on Andrew Owen's OpenSE BASIC and ULA+
- Industry standard 9-pin and 25-pin Serial and Parallel port connections at rear for printing and local networking
- Rear mic/ear combined audio jack for backwards software compatibility
An optional third party Office Productivity package, GUI OS on ROM cartridge, mouse, RGB monitor and printer would be sold separately and also offered for the consumer and business Spectrum models in special package deals.
The QL originally retailed for around £399 and I believe Sinclair could have produced an improved consumer Spectrum for the same price or less with those aforementioned features.
There could also have been a separate blitter board expansion that connected at the rear and would essentially be a graphics chip offering new resolutions and more colours.