CPU 68080

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Derek_Stewart
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Re: CPU 68080

Post by Derek_Stewart »

Hi,

I doubt any search engines will find me or the Q68, but that remains to be scene.

I was gonna create a web site for the Q68, Q60, and other things I am struggling to make. But I have not had time to do this.

Orders for the Q68 are taken via the QL Forum either by registering interest in the Q68 Message thread in the Hardware section
viewtopic.php?f=2&t=2203#p20071

or sending Private Messgage.

I will try to respond to forum messages and PMs immediately.

But bear in mind there is a fault in the QL Forum PM message setup somewhere, where the system does not send an email notification of a received PM. And yes, before eberyone jumps on me to say have to set the correct setting in the USER Profile... yes of course.

The answers to your questions:
Brane2 wrote:Is it cheap and open source ?
I am not sure what is cheap, the price for a Q68 board is £150 and had ever inreased in price since I built the first batch. The EU have tried to incurr extra costs for Import Tax, but I usually pay that and do not pass this on to the end user.

WIth regards to Open Source, the only part of the Q68 that is closed is the FPGA code and the PCB design details.

The operating system: SMSq/E, Minerva are Open Source, Applications Software are all supplied with source code (where available)
Brane2 wrote:Can I play with the code ?
You can re-programme the FPGA with your own code, but since the Q68 FPGA code, which I only have a JEDEC file, is closed, I do not know how you would get the Q68 back without returning the Q68 to me for re-programming the FPGA.

The Q68 FPGA code implements a 68000 CPU, which like Motorola/FreeScale do not issue the core code of the 68000 CPU in the QL.

What implementations are you planning?

Please note, I am not creating an update job here, in general, I will reprogramme the FPGA with updated core code for minimal cost. I can hear you say, but I want it all for nothing...
Brane2 wrote:Can I readilly dapt or modify the HW ?
If you buy the hardware you are free to modify it how you want. Since I do not know our skill level, I can not comment on your ability to perform the modifications.
Brane2 wrote:If I run the original QL program, I want original experience.
Yes, the Q68 can run SMSQ/E and Minerva operating system, so can run the majority of all QL software.

But where the application software accesses the QL hardware directly, there is a problem. But on saying all that software written for the QL should use the operating system to access the hardware.
Brane2 wrote:I want microdrives ( minus their unreliability) and want compact machine of the time.
Why?

Microdrives can store 100K of data, which is more like 80K on a good day.

If must use a Microdrive, you can create a network connection to the QL with Microdrives, using SerNET, EtherNET, QLUB

Personally, I stopped using microdrives in 1989, when I got a Trump card. It made a good computer computer an excellent computer.

Maybe an Q68 enhancment would be vDRIVEql, but the Q68 has dual SDHC card access of SDHC cards upto 32Gb

The SDHC card I supply is 4Gb, with SMSQ/E and all the QL software available in one place.also includes Black Phoenix, QL/E if you can set up your own environment. Where I supply sample boot files.
Brane2 wrote:One of great QL's appeal is that the user was always close to "the metal" and soldering iron.
The Q68, is the same as a QL, there is an expansion port, I2C header, Serial port for possible expansion.
Brane2 wrote:I wasn't prevented or afraid to experiment with it in crazy ways.
If I managed to release the smoke out of something, it was easy to fix.
Yes I can usually fix most things.
Brane2 wrote: Outside of that, we are in "compete with PC" territory.
And I can see none of them coming even close to competing with PC.
Well this is the problem, ask your self, how many people have a PC, how many can programme the PC, either Windows or Linux, how many use a Mac and can programme it.

Relate this back to the QL community, I think the number of QL programmers are very few, as I do not see much new application software coming out.

Only in the last 10 years has most of all QL operating systems, applications software, games become freely available due the efforts of a few people.which I am eternally grateful.

Personally I have 5 working PCs running Linux or Windows, a couple of MACs - do not like operating system. And other retro computer in storage.

The QL seems to take presence...

Right back to sleep.


Regards,

Derek
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Re: CPU 68080

Post by Nasta »

Apparently there are several mask sets for the 68060 and the accelerators that can run at 100-105MHz require a 'version 6' 060 (mask code 71E41J). Some have reported up to 133MHz overclockability. I have tried to find out how RC, LC, EC version differences correspond to overclockability but was not very cuccessful. I would expect that EC should be more overclockable given that there was an EC 75MHz version when only 66MHz was available for RC and LC, and only near end of life did the 75MHz rating appear for the RC and LC.


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Peter
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Re: CPU 68080

Post by Peter »

Nasta wrote:Apparently there are several mask sets for the 68060 and the accelerators that can run at 100-105MHz require a 'version 6' 060 (mask code 71E41J). Some have reported up to 133MHz overclockability.
Overclockability statements regarding machines run only with Atari/Amiga OS should be seen with lots of caution. I could heavily overclock the Q60 under SMSQ/E and QDOS also. But for example compiling GCC or Linux tasks heavily using the FPU could still result in instabilities.
Nasta wrote:I would expect that EC should be more overclockable given that there was an EC 75MHz version when only 66MHz was available for RC and LC
I'd expect the same.
Nasta wrote:and only near end of life did the 75MHz rating appear for the RC and LC.
As far as I know, the full blown 68060 never appeared with 75 MHz, except fakes. That's why the Q60/80 used the LC version.


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XorA
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Re: CPU 68080

Post by XorA »

Overclockability statements regarding machines run only with Atari/Amiga OS should be seen with lots of caution. I could heavily overclock the Q60 under SMSQ/E and QDOS also. But for example compiling GCC or Linux tasks heavily using the FPU could still result in instabilities.
This is very true, almost everyone on Amiga scene I see has 2 crystals, the fast one for running demos and the slow (not oveclocked one) for running serious stuff.


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Peter
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Re: CPU 68080

Post by Peter »

Brane2 wrote:Ethernet is not bad, but for much everything else, I want the opposite - access to modern monitors and old periphery.
I don't like widescreen monitors for retro computing at all. If anything is taking away the old time feeling, it's a 16:9 screen.
I prefer VGA because it is very easily converted to HDMI if needed, but still allows decent 4:3 monitors.
The Qzero supports HDMI, so the knowhow is here. But I still don't like it for QL purposes.

It's all a matter of taste - but I doubt that going back to microdrives on one hand, while rejecting anything below HDMI on the other hand, is a very common taste...


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NormanDunbar
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Re: CPU 68080

Post by NormanDunbar »

Brane2 wrote:BTW, search engine has trouble finding right Derek either.
Derek Stewart. He's on this forum. The thread you are searching for is this one..

viewtopic.php?f=2&t=2203


Cheers,
Norm.


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XorA
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Re: CPU 68080

Post by XorA »

Brane2 wrote:
Peter wrote: It's all a matter of taste - but I doubt that going back to microdrives on one hand, while rejecting anything below HDMI on the other hand, is a very common taste...
Microdrive is small and unobtrusive. It's also the essence of what QL is - using stuff in unintended ways to achieve the goal with unexpected efficiency.
Lose it and you lose part of its soul. While having it, no one forces you to use it 100% of the time.
Nothing else can really replace it. If you use unit with SD card, for example, you've just lost that essence.
You would be ruining that basic principle on the head and using far more capable hardware and cripple it to fit your form.

And this wouldn't be really computing, but more like playing with retro stuff to soothe your soul.

With monitor, it is different. It is big, it needs some space and it better be used, whether you use with QL or not.
So it burdens your QL stuff. Your card stops being like Raspberry Pi that you can carry around in your pocket and lose
it in any drawer and starts demanding its own ecosystem - bunch of stuff that you have to have around.

At that point, you aren't doing anything useful with it.

Yes, you can tear down any part of it and replace it with far more capable hardware, used with far lower efficiency.
But along with it you are tearing fundamental principles of the machine.

I don't see original team redoing QL with parts for Q68 in the same way with the same tech.
This would be like watching Daemon Hill driving a golf cart during golfing game - boring.

For me, essential parts of QL experience is LEARNING.
Sure, looking at Microdrive from pure customer perspective, it's punny.
Why would anyone care for piece of tape with 80-100 kB on it ?

But if you want to know how stuff is done, its treasure of knowledge. It's practically encapsulation of whole R&D cycle in one small product.
Microdrive might be old, but magnetic recording is not ?
Want to know how it's done and how could it be done?
What better way than opening a magic box, learning from it and redoing it yourself ?

Same goes for many other fundamental principles that are glued within it.
I really don't care to have machine patched with a million mindless patches while losing its soul.

Yes, 68000 can eat cycles like a pig. But I don't care about someone patching it with stuff from the future.
That's not how one is supposed to rely on his wits. I care about how one could use that experience to learn from it and
improve it in competitive way.
So all those 68000 implementations that are just throwing extra shovels of Verilog code and virtual gates at the problem are meaningless to me.
Had Sinclair's team had access to them, would they use them in the same lame way ?
I think not.

Having a QL as a machine that one is just supposed to use without understanding or caring about fundamentals is not how I see it.
What's there to especvialy like on that machine as ordinary user ?
Microdrives ? Speed ? Software ? Simplicity ?

I'll give it multitasking, but even that was lacking. There wasn't much that 68008's CPU time could be spread over.
And what would you use it for, anyway ? There weren't that many decent programs.
And those few that were available, were soon bested by competition.

For me, all that is left, is fundamental principle - using what's available and carefully combining it in unintended ways to achieve unexpected effects.
I must say I agree with Peter here. Part of the interest for me in the QL is actually how much of a capable machine it is even though it was a design nightmare. Really enjoying brushing up on my old school C seeing as I work for a team that designs CPU’s with hundreds of cores and insane clock speeds.


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M68008
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Re: CPU 68080

Post by M68008 »

Brane2 wrote:
Peter wrote: BTW, would they care to share the data on how exactly does 68000 fetch instruction opeerands ( order and timings)?
Here is a good doc:
http://nemesis.hacking-cult.org/MegaDri ... /Yacht.txt

Some info about pre-fetching:
http://pasti.fxatari.com/68kdocs/68kPrefetch.html

Mister FPGA can run the fx68k core (https://github.com/ijor/fx68k) which is cycle accurate, including bus accesses. It seems to be the most accurate 68K core around, based on reverse engineering the IC and using the original microcode.


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Peter
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Re: CPU 68080

Post by Peter »

XorA wrote:Part of the interest for me in the QL is actually how much of a capable machine it is even though it was a design nightmare.
The QL was really not a good hardware design. And not all of that can be blamed on Sir Clive's influence and time pressure.
I'd love to know how the QL hardware would look if hardware genius Richard Altwasser had stayed with Sinclair.
Still it was the only affordable 68K machine with preemptive multitasking at the time. That made it technically interesting for me.


Derek_Stewart
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Re: CPU 68080

Post by Derek_Stewart »

HI,

A more interesting point would be, if Alan Sugar had not cancelled the QL and developed it like the Spectrum 128. The QL would had a 3" Disk Drive, instead of Microdrives.

I think the heart and soul of any computer system us the operating system.


Regards,

Derek
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