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whm1974
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the most advanced 80's 8-bit CPUs?

Thu Oct 26, 2017 7:53 pm

OK I was thinking about the 8-bit computers and their CPUs I've used since the early 80's. And come to think of it, I've never seen an IBM PC or it's clones in action(outside of offices) or used one until 90' or 91'. My stepfather had a 800XL and I used an Apple IIe in school, and my best friend's family at the time used the Commodore 64. I first computer I owned was the Texas Instruments Ti94/A4(IIRC) which I used for playing Parsec and learning BASIC.

The 80's Microcomputers I'm most familiar with are the 800XL, Commodore 64 and the Apple IIe. I've used the Atari 800XL with Paperclip to write school papers until late High school when I switched to the Tandy 1000/TL2 and WordPerfect.

This was just to provide some background.

Now my questions are what were the most advanced 8-bit CPUs and 8-bit home computers available during the 80's? The only one I've seen in person was the Tandy color computer(III?) which I played a few games on the demo unit at the Local Radio Shack. Which used the Motorola 6809 CPU.

Were there any 8-bit processors back then with wider address buses then 16-bit, like 20 or even 24?
 
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Re: the most advanced 80's 8-bit CPUs?

Thu Oct 26, 2017 8:52 pm

Most of the 8 bit CPUs are actually 70s designs that became prominent in the 80s. By the time the mid-to-late 80s rolled around, 16 and even 32bit CPUs were being introduced by virtually everyone (including "CPU companies" everyone has almost forgotten about, like Xerox and National Semiconductor). Decades are funny that way. The quintessential New Wave song "Heart of Glass" is actually a song from the 70s; "Pretty Hate Machine" is actually an album from the 80s. Tail-fins started getting put on cars in the 40s; some of us were sending email in the 80s. Things sometimes take long enough to become popular that they get associated with a decade later than their birth.

Of the classic 8-bit CPUs, the most prominent was 6502, which is in most of the non-Radio Shack "personal computers" of the day -- most notably the Apple ][, Commodore PET/64/Vic-20, and Atari models in all their variants, as well as lot of less-famous machines from TI, Acorn, etc, not to mention the first gen of consoles such as the Atari VCS aka 2600 and NES. The 6502 actually had some pretty sophisticated (for its era) addressing modes... that virtually nobody used because they were too slow. But the CPU itself was nearly ubiquitous, and coders learned to wring everything out of it (and then some).

The Z80 found in the various TRS machines wasn't one I particularly liked from a coding standpoint but its influence lives on, as it was an advance on the 8080 which itself became the 8086/8088 in the first IBM PCs, so the folks who cut their teeth on Z80 assembly had the world open up around them. The 8088 ironically was a bit of a throwback in that it was kind of a stunted 8/16bit processor in an 80s decade that was already going fully 16bit, but it was compatible with the full non-stunted 8086 and later 80286 etc. Which themselves were full of unfortunate design decisions (segments! separate IO address space! broken supervisor modes!) but came to rule the world anyway.

The Tandy Color Computer and a few others used the Motorola 6809, an iteration of the 6800. The 6800 later grew more directly into the 68000, an 80s 16/~32 bit CPU found in the first Macs (famously introduced in a certain year in the 80s). The 68000, which could also be found in workstations of the day from Sun, Apollo, and SGI, was maybe the most powerful widely-available processor of its era (at least I thought so at the time, though I don't entirely trust the judgement of 80s-me in retrospect. That guy was a little too enamored of theoretical notions like of ISA orthognality). At least it was top dog in the early 80s; by the late 80s you had the 80386 and 80486 to argue about.

Supposedly Wozniak considered using the original 6800 in his Apple I design but decided on the 6502 because it was cheaper -- probably the same decision made at many companies, which explains why the 6502 had so many design wins and the 6800 is relatively poorly-remembered. It's interesting to imagine what would've happened had Woz decided differently, and the subsequent Mac was able to run widely available Apple ][ software, particularly in schools (albeit only if there had been a way for Macs to read 5.25" floppies). But Woz was Woz, and if he was willing to live with the absurd video memory layout in the Apple ][ to save a few cents, he certainly wasn't going to pick a more expensive CPU.

My favorite CPU of the 80s, at least of the ones I used and coded against, was the crazy heart of the Xerox Alto. Nevermind it was a 16bit CPU at a time when that was rare, and was actually built out of multiple MSI 74181 bit-slice ALUs (among other things). The coolest thing about it was that it could be reconfigured with user-defined microcode. Put the right boot disk in, and it would come up as a hardware LISP machine. Don't like the instruction set architecture? Design your own!
 
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Re: the most advanced 80's 8-bit CPUs?

Thu Oct 26, 2017 10:21 pm

As I recall from reading DOS books from the early to mid 90's giving a brief history of DOS and CP/M, Gary "what his name" the developer of CP/M at first wouldn't bother supporting the Intel 8086 with it's 20bit address space when it was released because he thought that no would be able even use 1024K of memory at all. That was a stupider idea then the one whoever at IBM had that no one will never need more then 640K when designing the IBM PC. I wonder what Gary and the IBM design team thought of the 68000 with it's 24-bit address bus?

I wonder what kind of 8-bit CPU if the designers back in the late 70's could come up if they had some of the knowledge that was learned later and better FABs with much smaller processes?
 
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Re: the most advanced 80's 8-bit CPUs?

Thu Oct 26, 2017 10:27 pm

UberGerbil wrote:
The 6800 later grew more directly into the 68000


This is a myth actually. The 68K was a clean sheet design. The 6800 peripheral chip compatibility it initially had was tacked on and was removed fairly early on.
 
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Re: the most advanced 80's 8-bit CPUs?

Thu Oct 26, 2017 10:53 pm

Western Digital was even in the CPU business early on. They produced an LSI-11 clone that formed the basis of the Alpha Micro AM-100 system (a 16-bit system that leveraged the then-popular S-100 bus, which was originally developed for the 8080). For a while WD also sold systems based on a custom CPU which executed UCSD Pascal bytecode natively in hardware.

Zilog also produced a 16-bit follow-on to the Z80, the Z8000. It never caught on.

There were a lot of competing architectures back in the day, and even up until the start of the 32-bit era. The total dominance of x86 and ARM today feels a little weird to those of us who lived through the early days of the tech revolution. Sure, other architectures are still around (MIPS, POWER, SPARC...) but they are small niche players.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 12:13 am

Well hey...decent thread topic WHM (and a couple informative responses already). I've probably used 6502 and Z80-based devices countless times, but this was before I had any real understanding of the internals (and it was mostly to play games). As has been mentioned, most of the newly released CPUs were 16-bit or better by the 80's, so limiting it to a decade doesn't work well.

A better phrasing might be: What were the most powerful 8-bit CPUs to see meaningful usage?

I'd ask the same thing of 16-bit, but it seems there were many more players by that time, and quantifying how powerful they were might be difficult in some cases.
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 1:42 am

The Egg wrote:
Well hey...decent thread topic WHM (and a couple informative responses already). I've probably used 6502 and Z80-based devices countless times, but this was before I had any real understanding of the internals (and it was mostly to play games). As has been mentioned, most of the newly released CPUs were 16-bit or better by the 80's, so limiting it to a decade doesn't work well.

A better phrasing might be: What were the most powerful 8-bit CPUs to see meaningful usage?

I'd ask the same thing of 16-bit, but it seems there were many more players by that time, and quantifying how powerful they were might be difficult in some cases.

Yeah but Apple, Atari, Commodore, and a few others were still selling 8-bit machines until the early 90's. As I recall, both Atari and Commodore's 8-bit lines were the lowest cost computers by the late 80's. I think the last time I've used an 8-bit system was an Apple IIe machine in one of the school labs when I left High school in 1993.
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 4:34 am

The 80s also included some pretty decent 32-bit CPUs like the Motorola 68030.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 5:07 am

JustAnEngineer wrote:
The 80s also included some pretty decent 32-bit CPUs like the Motorola 68030.

True, but I am wondering just how far you could push an CPU with a 8-bit ISA. Is possible to design and produced a multi-core 8-bit processor with the same performance as a Goldmont Atom or even better?
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 6:28 am

You could certainly get the same (or better) IPC. Problem is, each of those instructions does a lot less because data needs to be operated on 8 bits at a time. Just multiplying a pair of 32-bit numbers together would take many instructions. The 8-bit memory bus would also be a major bottleneck.

To get equivalent overall performance on similar applications the CPU would probably need to be clocked at 50+ GHz, with the memory operating at the speed of (hypothetical) DDR7.

I remember someone predicting (back around 1978 or so) that in 10 years we'd have Z80s running at 500 Mhz, using gallium arsenide instead of silicon. :lol:
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 6:33 am

whm1974 wrote:
JustAnEngineer wrote:
The 80s also included some pretty decent 32-bit CPUs like the Motorola 68030.

True, but I am wondering just how far you could push an CPU with a 8-bit ISA. Is possible to design and produced a multi-core 8-bit processor with the same performance as a Goldmont Atom or even better?


A bunch of modern special-purpose applications are using 8 bit operations in situations where the higher precision isn't needed. Some (not all) neural networks can operate with very low precision weighting values and 16-bit or even 8-bit operations can do the job more efficiently simply because it takes less hardware to perform the calculations. Of course, the actual hardware that is performing these operations is light years away from a Z80 or other 8-bit 80's era processor. Furthermore, just because the mathematical operation is on a 16 or 8 bit value doesn't mean that the rest of the architecture is similarly constrained when it comes to moving data around (i.e. these parts have massive bandwidth and don't rely on an 8-bit bus).
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 6:59 am

The 6502 derivative in the Turbografx-16 could address up to 2MB, apparently.
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 7:46 am

just brew it! wrote:
You could certainly get the same (or better) IPC. Problem is, each of those instructions does a lot less because data needs to be operated on 8 bits at a time. Just multiplying a pair of 32-bit numbers together would take many instructions. The 8-bit memory bus would also be a major bottleneck.

To get equivalent overall performance on similar applications the CPU would probably need to be clocked at 50+ GHz, with the memory operating at the speed of (hypothetical) DDR7.

I remember someone predicting (back around 1978 or so) that in 10 years we'd have Z80s running at 500 Mhz, using gallium arsenide instead of silicon. :lol:

Use PCIe and 64-bit address space maybe? At least be able to use PCIe 1x slots anyway and DDR3 memory anyway. I have no idea if a 8-bit CPU can even make full use of 2 to 4 GB of memory however. Maybe something with 32 cores at 1 to 3 Ghz perhaps?
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 7:49 am

I had a Commodore 64 and did some assembly language programming on it. The biggest problem I had was the lack of registers A, X and Y. To hinder things even more, the X and Y registers were really for indexing the A register's access to memory.

The Commodore 64 actually had a 6510 which was a 6502 with an I/O port. The I/O port was used for memory bank switching so if you were writing in assembly language then you could drop the BASIC ROM out of memory and replace it with RAM. If you were doing graphics you could similarly drop the character bank out and gain RAM there. It actually had a full 64k of RAM but a large chunk of it was covered with ROMs and interface chips (VIC for video, SID for sound).
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 7:55 am

notfred wrote:
I had a Commodore 64 and did some assembly language programming on it. The biggest problem I had was the lack of registers A, X and Y. To hinder things even more, the X and Y registers were really for indexing the A register's access to memory.

The Commodore 64 actually had a 6510 which was a 6502 with an I/O port. The I/O port was used for memory bank switching so if you were writing in assembly language then you could drop the BASIC ROM out of memory and replace it with RAM. If you were doing graphics you could similarly drop the character bank out and gain RAM there. It actually had a full 64k of RAM but a large chunk of it was covered with ROMs and interface chips (VIC for video, SID for sound).

OK put 32 8-bit registers in the CPU design I'm thinking of.
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 8:34 am

whm1974 wrote:
OK put 32 8-bit registers in the CPU design I'm thinking of.


On the CPU front (not the memory) it sounds like you're aiming for something very much like the Atmel (now Microchip) AVR.

These micro-controllers have 8-bit RISC cores with 32 GPRs. Some have hardware multiply (though I don't think they have divide). And the nice think about them (compared to the PIC) is that for data memory address space they have a clean 64KB with no bank switching. The XMegas are more 8/16-bit hybrid I think.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 8:40 am

whm1974 wrote:
just brew it! wrote:
You could certainly get the same (or better) IPC. Problem is, each of those instructions does a lot less because data needs to be operated on 8 bits at a time. Just multiplying a pair of 32-bit numbers together would take many instructions. The 8-bit memory bus would also be a major bottleneck.

To get equivalent overall performance on similar applications the CPU would probably need to be clocked at 50+ GHz, with the memory operating at the speed of (hypothetical) DDR7.

I remember someone predicting (back around 1978 or so) that in 10 years we'd have Z80s running at 500 Mhz, using gallium arsenide instead of silicon. :lol:

Use PCIe and 64-bit address space maybe? At least be able to use PCIe 1x slots anyway and DDR3 memory anyway. I have no idea if a 8-bit CPU can even make full use of 2 to 4 GB of memory however. Maybe something with 32 cores at 1 to 3 Ghz perhaps?

You can do something screwy like the 8086/8088 segment registers to address more memory. But that hurts performance too since you're constantly reloading the segment registers to access the extra address space.

Unless you've got wider ALUs to do the address calculations and wider address and data buses, dealing with lots of RAM is going to be messy and/or inefficient, pretty much by definition. And once you've got the wider ALUs and buses, you're not an 8-bit ISA any more.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 8:49 am

just brew it! wrote:
whm1974 wrote:
just brew it! wrote:
You could certainly get the same (or better) IPC. Problem is, each of those instructions does a lot less because data needs to be operated on 8 bits at a time. Just multiplying a pair of 32-bit numbers together would take many instructions. The 8-bit memory bus would also be a major bottleneck.

To get equivalent overall performance on similar applications the CPU would probably need to be clocked at 50+ GHz, with the memory operating at the speed of (hypothetical) DDR7.

I remember someone predicting (back around 1978 or so) that in 10 years we'd have Z80s running at 500 Mhz, using gallium arsenide instead of silicon. :lol:

Use PCIe and 64-bit address space maybe? At least be able to use PCIe 1x slots anyway and DDR3 memory anyway. I have no idea if a 8-bit CPU can even make full use of 2 to 4 GB of memory however. Maybe something with 32 cores at 1 to 3 Ghz perhaps?

You can do something screwy like the 8086/8088 segment registers to address more memory. But that hurts performance too since you're constantly reloading the segment registers to access the extra address space.

Unless you've got wider ALUs to do the address calculations and wider address and data buses, dealing with lots of RAM is going to be messy and/or inefficient, pretty much by definition. And once you've got the wider ALUs and buses, you're not an 8-bit ISA any more.


Out of curiosity, do you consider the 68000 a 16-bit or 32-bit CPU. A lot of people think of it as a 32-bit CPU because of its 32-bit registers. But its ALU internally was only 16-bit and so was the data bus. Address bus was 24-bit.

The 68k line first received a 32-bit ALU with the 68020.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 8:50 am

duplicate, please delete.
Last edited by srg86 on Fri Oct 27, 2017 8:52 am, edited 1 time in total.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 8:51 am

The problem with this sort of question is there are several ways to look at it:

Performance: Processing power, memory access speed, bus speed etc.
Library: how much software was written for that processor
Market share: how many machines actually sold

Considering how many machines were created and how much software was available and then future impact I'd say the most powerful was the 8086 and it's weird brother the 8088.

In raw performance I think there is a z80 compatible chip that runs at 20mhz that was an absolute beast in comparison to other 8bit machines but it was produced in the mid 90's.

The 8086 could also be overclocked to 20mhz making it a really fast machine but that required some modification of the system board by replacing crystals and putting heat sinks on various components and this was also a 16bit chip not an 8bit one.

I believe the commodore 128 could also be overclocked to 4mhz? which might have made it the fastest real 80's 8bit computer.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 1:01 pm

srg86 wrote:
Out of curiosity, do you consider the 68000 a 16-bit or 32-bit CPU. A lot of people think of it as a 32-bit CPU because of its 32-bit registers. But its ALU internally was only 16-bit and so was the data bus. Address bus was 24-bit.

The 68k line first received a 32-bit ALU with the 68020.

I would consider the 68000 to be a hybrid 16/32 bit CPU, in much the same way that the 8088 was a hybrid of 8- and 16-bit.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 1:51 pm

The most powerful 8-bit CPU DESIGN in the BAD OLD DAYS was the 6809.

https://en.wikipedia.org/wiki/Motorola_6809

It quickly gained a following in demanding arcade machines.

It was pretty beefy, but got outshone by the 68000 released only a year later. The two weren't source-compatible, so the 6809 died off in no time.

I'm sure there are better 8-bit micro-controllers released since then, but this really was the Swan's Song for powerful 8-bit computing.

The 6502 had many more design wins because it was WAY cheaper. We're talking $25 for a processor, in a time when the Motorola 6800 and Intel 8080 cost several hundred dollars. It also had pretty good performance (despite the low price), but came with a lot of restrictions.

256-byte fixed stack (instead of 16-bit), ONE accumulator, and 8-bit index registers. Really primitive compared to most other architectures. But when you saw that $25 price, it suddenly made it all worth it :D
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 2:55 pm

The Egg wrote:
A better phrasing might be: What were the most powerful 8-bit CPUs to see meaningful usage?

I'd ask the same thing of 16-bit, but it seems there were many more players by that time, and quantifying how powerful they were might be difficult in some cases.


Well, clearly the Intel 8088, right? :)
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 3:52 pm

defaultluser wrote:
I'm sure there are better 8-bit micro-controllers released since then, but this really was the Swan's Song for powerful 8-bit computing.

With the proliferation of more powerful 16- and 32-bit designs, 8-bit has been relegated almost exclusively to the embedded control market. Microchip has produced thousands of variants of its 8-bit PIC microcontrollers, which saw (and still see) extensive use in automotive and appliance control applications. These are low pin count devices running at just a few MHz, costing less than 50 cents each in quantity.

Need an ultra-cheap 8-bit controller with only 384 bytes of program memory, 16 bytes of RAM, and 3 discrete I/O pins? They've got you covered. Need something beefier? They make 16-bit chips (with their own proprietary core design), and 32-bit (MIPS and ARM based) microcontroller chips too, with clock speeds up to 120 MHz.
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 4:53 pm

I love how the default quantity is 3000
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 6:22 pm

just brew it! wrote:
srg86 wrote:
Out of curiosity, do you consider the 68000 a 16-bit or 32-bit CPU. A lot of people think of it as a 32-bit CPU because of its 32-bit registers. But its ALU internally was only 16-bit and so was the data bus. Address bus was 24-bit.

The 68k line first received a 32-bit ALU with the 68020.

I would consider the 68000 to be a hybrid 16/32 bit CPU, in much the same way that the 8088 was a hybrid of 8- and 16-bit.

As do I. Just wondering, but could anybody even put a full blown 32-bit CPU on a Microcomputer board in the late 70's?
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 6:32 pm

just brew it! wrote:
whm1974 wrote:
just brew it! wrote:
You could certainly get the same (or better) IPC. Problem is, each of those instructions does a lot less because data needs to be operated on 8 bits at a time. Just multiplying a pair of 32-bit numbers together would take many instructions. The 8-bit memory bus would also be a major bottleneck.

To get equivalent overall performance on similar applications the CPU would probably need to be clocked at 50+ GHz, with the memory operating at the speed of (hypothetical) DDR7.

I remember someone predicting (back around 1978 or so) that in 10 years we'd have Z80s running at 500 Mhz, using gallium arsenide instead of silicon. :lol:

Use PCIe and 64-bit address space maybe? At least be able to use PCIe 1x slots anyway and DDR3 memory anyway. I have no idea if a 8-bit CPU can even make full use of 2 to 4 GB of memory however. Maybe something with 32 cores at 1 to 3 Ghz perhaps?

You can do something screwy like the 8086/8088 segment registers to address more memory. But that hurts performance too since you're constantly reloading the segment registers to access the extra address space.

Unless you've got wider ALUs to do the address calculations and wider address and data buses, dealing with lots of RAM is going to be messy and/or inefficient, pretty much by definition. And once you've got the wider ALUs and buses, you're not an 8-bit ISA any more.

As messy as having to use bank switching? As I recall some of the 8-bit machines by the late 80's could have up to 2MB of total memory. Surly a large flat address space has to be better then resorting to bank switching?
 
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 6:59 pm

whm1974 wrote:
Just wondering, but could anybody even put a full blown 32-bit CPU on a Microcomputer board in the late 70's?

The AM-100 (16-bit) was a pair of S-100 cards connected to each other via a ribbon cable, occupying 2 adjacent slots of an S-100 backplane. So I'd say the answer is "no". (The 5 large chips on the right side of the second board are the Western Digital WD16 CPU; so really a CPU chipset as opposed to a single CPU chip.)

To give you a sense of scale, S-100 cards were 5x10 inches.

whm1974 wrote:
As messy as having to use bank switching? As I recall some of the 8-bit machines by the late 80's could have up to 2MB of total memory. Surly a large flat address space has to be better then resorting to bank switching?

To handle a flat address space efficiently you need to be able to quickly perform address calculations on the full address range -- i.e., you need machine registers which are at least as wide as your addresses, and (ideally) ALUs of that width as well. So you're either doing something that resembles bank switching, or your CPU starts to have a lot of wider registers and data paths in it.

x86's segmented addresses were kind of like a form of bank switching where the banks were allowed to overlap on 16-byte boundaries. The effective address of a memory reference was equal to the contents of a 16-bit segment register multiplied by 16, plus a 16-bit offset, effectively giving you a 1 MB address space. You could also set all of the segment registers to the same value, effectively giving you a flat 64 K address space (this technique was commonly used to facilitate porting of assembly language code which was originally written for the 8080).
Nostalgia isn't what it used to be.
 
whm1974
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Re: the most advanced 80's 8-bit CPUs?

Fri Oct 27, 2017 7:40 pm

just brew it! wrote:
whm1974 wrote:
Just wondering, but could anybody even put a full blown 32-bit CPU on a Microcomputer board in the late 70's?

The AM-100 (16-bit) was a pair of S-100 cards connected to each other via a ribbon cable, occupying 2 adjacent slots of an S-100 backplane. So I'd say the answer is "no". (The 5 large chips on the right side of the second board are the Western Digital WD16 CPU; so really a CPU chipset as opposed to a single CPU chip.)

To give you a sense of scale, S-100 cards were 5x10 inches.

whm1974 wrote:
As messy as having to use bank switching? As I recall some of the 8-bit machines by the late 80's could have up to 2MB of total memory. Surly a large flat address space has to be better then resorting to bank switching?

To handle a flat address space efficiently you need to be able to quickly perform address calculations on the full address range -- i.e., you need machine registers which are at least as wide as your addresses, and (ideally) ALUs of that width as well. So you're either doing something that resembles bank switching, or your CPU starts to have a lot of wider registers and data paths in it.

I'm still wondering what could be done with a 8-bit CPU w/ wide address space and large number of registers designed around a cleaned up and modernized ISA. And it would be a multi-core design as well.

If I was some filthy rich dude, I would have some of those CPUs made and give to a bunch of homebrewers and have them design a personal computer with modern features around it. I would do this just to see what they could come up with.

How do rich people could ever get bored??? There is so much to do!!!
 
whm1974
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Re: the most advanced 80's 8-bit CPUs?

Sat Oct 28, 2017 12:18 am

Here is a guy who built a 16 core 8-bit computer using only 32K of SRAM memory and 512K of Flash. It has Ethernet and a VGA port.
https://www.engadget.com/2013/06/24/16- ... -computer/
And this is back in 2013, so I wonder what he has built now?

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