Personal computing discussed
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thx1138r wrote:Back to the original question.
The motorola 68008 was essentially a 68000 with an 8-bit data bus. So you could call it a 8-bit computer although you would probably be better to call it a 8/16/32 hybrid and it came with either a 20 or 22 bit address bus. It did see one major usage in a small computer, the not very successful sinclair QL: https://en.wikipedia.org/wiki/Sinclair_QL
whm1974 wrote: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.
Aranarth wrote:My 8086 based Compaq DeskPro (1983) ran at 7 or 8 MHz. It was like having your own IBM360 once you added the 8087 math coprocessor and the MS FORTRAN compiler. I upgraded the CPU to the Japanese clone, an NEC V30 that ran at 10MHz. I had 640K ram and 2MB of extended memory in each of two Tall Tree Systems JRam cards. So, I had 4MB of extended memory and 704K of DOS memory. Both DoubleDos and DesqView could use this memory for task switching. At the time, that was flying!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.
whm1974 wrote:I wonder if it had any better success elsewhere such as the embedded market it was intend for?
thx1138r wrote:It had some at least, I remember when the sinclair QL came out, a few of it's detractors pointed out that the 68008 was used in some of the more upmarket washing machines of the day.
Topinio wrote:thx1138r wrote:It had some at least, I remember when the sinclair QL came out, a few of it's detractors pointed out that the 68008 was used in some of the more upmarket washing machines of the day.
Thanks, I just went looking for info on modern washing machines, having been reading for 5 years or more about smart ones so suspecting they probably use 3+ core CPUs, a good chunk of RAM and a Linux distro nowadays, and found all sorts of silliness and rise of the machines fun, but no actual hard details (yet). Anyone got any good info they can link?
The video at the end of that second link is great (IMO), how amazing that the touchscreen computer built into the fridge door can even show you what's inside!!!
just brew it! wrote:Zilog also produced a 16-bit follow-on to the Z80, the Z8000. It never caught on.
Takeshi7 wrote:I'm pretty sure the Z80 or MOS 6502 were the undisputed champs of 8-bit CPUs. The 6502 was clocked slower, but it had around 4x the IPC of the Z80, so they ended up pretty close in performance.
whm1974 wrote:Takeshi7 wrote:I'm pretty sure the Z80 or MOS 6502 were the undisputed champs of 8-bit CPUs. The 6502 was clocked slower, but it had around 4x the IPC of the Z80, so they ended up pretty close in performance.
Too bad the WDC 65816 wasn't more successful then it was. I still think that both Atari and Commodore should have released systems around the CPU to provide an upgrade path for users of their 8-bit lines. Yes I know the Apple IIgs was one of Apples best selling computers for awhile, but still.
derFunkenstein wrote:whm1974 wrote:Takeshi7 wrote:I'm pretty sure the Z80 or MOS 6502 were the undisputed champs of 8-bit CPUs. The 6502 was clocked slower, but it had around 4x the IPC of the Z80, so they ended up pretty close in performance.
Too bad the WDC 65816 wasn't more successful then it was. I still think that both Atari and Commodore should have released systems around the CPU to provide an upgrade path for users of their 8-bit lines. Yes I know the Apple IIgs was one of Apples best selling computers for awhile, but still.
One other 6502 descendant was much more popular. The Ricoh 5A22 was the heart of the Super Nintendo, for example, and that sold WAY more units than any 8-bit computer.
Non-x86 16-bit computers, for whatever reason, just gravitated towards the Motorola 68000. The Mac and the Amiga are the two most popular examples but Atari's ST used a 68000, too. The 68000 was also at the heart of arcade boards from Sega, Capcom, Konami, SNK (the Neo Geo) and plenty of others. The most famous arcade games of the late 80s and 1990s used some combination of a 68000, a Z80, and some special video and sound chips.
whm1974 wrote:Yeah but the Motorola 68000 was actually was a 32-bit CPU with a 16-bit data path and 24-bit address bus.
srg86 wrote:whm1974 wrote:Yeah but the Motorola 68000 was actually was a 32-bit CPU with a 16-bit data path and 24-bit address bus.
The Motorola 68000 was an otherwise 16-bit CPU (16-bit ALU and databus), just with 32-bit registers for forwards compatibility.
whm1974 wrote:srg86 wrote:whm1974 wrote:Yeah but the Motorola 68000 was actually was a 32-bit CPU with a 16-bit data path and 24-bit address bus.
The Motorola 68000 was an otherwise 16-bit CPU (16-bit ALU and databus), just with 32-bit registers for forwards compatibility.
Didn't know it had 16 bit ALU.
Takeshi7 wrote:I'm pretty sure the Z80 or MOS 6502 were the undisputed champs of 8-bit CPUs. The 6502 was clocked slower, but it had around 4x the IPC of the Z80, so they ended up pretty close in performance.
demolition wrote:The question is then whether the 6502 qualifies as an 80's CPU? Yes, it was used quite a lot in 80's computers, but the CPU itself was launched in 1975.
defaultluser wrote: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
[Jamie] has implemented the entire set of 80186 instructions in Verilog, and included some of the undocumented instructions too.
Not content to simply simulate a CPU, all the necessary peripherals for a complete working system have been worked into the design as well. There’s RAM, a UART, as well as CGA graphics and a PS/2 controller that is necessary if you’d like to actually use any sort of human input device.
blindsorrow wrote:Hudson Soft HuC6280 8-bit microprocessor operating at 1.79 MHz and 7.16 MHz. It features integrated bank-switching hardware (driving a 21-bit external address bus from a 6502-compatible 16-bit address bus), an integrated general-purpose I/O port, a timer, block transfer instructions, and dedicated move instructions for communicating with the HuC6270A VDC. P.us, it had an embedded 6-channel wavetable sound synthesizer that alternatively could output PCM samples at 5-bit resolution, or greater resolution by ganging sound channels. About 6 million produced for home market.
whm1974 wrote:blindsorrow wrote:Hudson Soft HuC6280 8-bit microprocessor operating at 1.79 MHz and 7.16 MHz. It features integrated bank-switching hardware (driving a 21-bit external address bus from a 6502-compatible 16-bit address bus), an integrated general-purpose I/O port, a timer, block transfer instructions, and dedicated move instructions for communicating with the HuC6270A VDC. P.us, it had an embedded 6-channel wavetable sound synthesizer that alternatively could output PCM samples at 5-bit resolution, or greater resolution by ganging sound channels. About 6 million produced for home market.
So can this 8-bit CPU directly access more then 1MG of RAM or is it still stuck with a mere 64K without resorting to Bank Switching?
bthylafh wrote:Sort of related, Alan Cox of Linux kernel fame is developing a Unix-like operating system aimed at these old computers, called Fuzix:
https://github.com/EtchedPixels/FUZIX
http://www.fuzix.org/
One target is the RC2014 modular computer:
https://rc2014.co.uk/