Use of MOVE16

[SpeedGeek]

Originally Posted by Karlos

System programmers, at least any worth the title, will just avoid it if they know it's a problem. Playing roulette with instructions that are potentially crash inducing is best up to application developers.

The problem is that Copymem improvement patches are applied to system functions not applications. Move16 is not the only instruction which is potentially crash inducing. Indeed the Amiga and the pre-68040 CPUs had been crashing years earlier before the 68040 was available.

Motorola documented the various errata conditions so system programmers could understand how to properly use Move16 (and other instructions) to avoid the crash. This means CPU library developers should not have played roulette either.

Originally Posted by Thomas Richter

Right. On a retro system. Right. Instead of avoiding just software using instable instructions. Right... Which 060 based turbo board would you recommend for my A2000 exactly?

There are no 060 based Turbo Boards which support Burst cycles to the Zorro2 bus so I'm afraid I can't recommend one which would make you a satisfied customer.

[patrik]

Originally Posted by SpeedGeek

There are no 060 based Turbo Boards which support Burst cycles to the Zorro2 bus so I'm afraid I can't recommend one which would make you a satisfied customer.

Can burst to the Zorro2 bus with a 060 card be implemented safely?

[SpeedGeek]

Originally Posted by Bruce Abbott

It should be treated like any other hardware issue, either with the OS hiding it from the application so it doesn't have to worry about it, or at least telling the app what it can safely do. An application should be designed to be as inclusive as possible, without requiring the user to make decisions about what the hardware is (maybe) capable of.

We are a small community now, and fracturing it further by developing code that only works on specific hardware just fractures it more. It's bad enough that many of us can't run some interesting applications because we don't have the right OS or CPU, but limiting it to particular revisions of certain hardware combinations is far worse - unless your aim is to deliberately limit the audience for your application - which is just mean.

Yes. The Amiga is a retro platform, so we should stick to the retro rules.

Rule #1: It shall be done as was proscribed back-in-the-day. Commodore said MOVE16 was a no-no so it should remain so. Developers of new hardware shouldn't have to worry about supporting it.

Rule #2: rules were made to be broken. Gould couldn't stop us doing whatever we liked with our hardware, and that still applies today!

As we are painfully aware, #2 caused no end of trouble. All those coders thinking they were so hot, when they were really just lazy. Real programmers figure out how to get stuff done within the rules. This is even more important today with the increasing variety of hardware combinations people have.

Commodore did not say MOVE16 was a no-no (Please read the RKRM). Mike Sinz said Move16 is not 100% supported and warned developers to be careful with Move16 (Please read the Enforcer documentation).

If and when I can find some time, I will try to make a safer version of CMQ&B040 which plays a little better with the rules. It won't be as fast and it won't be 100% safe either.

Motorola and Commodore provided choices for Amiga users, but they did not provide perfection.

Originally Posted by patrik

Can burst to the Zorro2 bus with a 060 card be implemented safely?

Nope. Did you not read the previous posts on this thread?

BTW, The Zorro2 bus is a 68000 protocol bus and the 68000 CPU absolutely does NOT support Burst.

[No.3]

phew, the effect of Move16 is very drastic!

Did some own tests => original CopyMem does ~13.7 MB/s, my own copy mem ~14,5 MB/s - that's the same as a 030 patch delivers, but a 060 copymem patch reaches ~18,9 MB/s !!

[Bruce Abbott]

Originally Posted by SpeedGeek

Commodore did not say MOVE16 was a no-no (Please read the RKRM).

Which 'RKRM' would that be, and what page do I read?

Mike Sinz said Move16 is not 100% supported and warned developers to be careful with Move16 (Please read the Enforcer documentation).

Ah, I see the problem now. I had assumed that since Michael Sinz was head of the Amiga OS group and the Enforcer was provided on the official developer disks that he was speaking for Commodore.

[Thomas Richter]

The RKRMs predate the support of the 68040 in AmigaOs, so it is not a miracle that nothing is said about MOVE16 or 68040 (leave alone 68060) specifics. They are essentially stuck at the state of Os 2.1.

[SpeedGeek]

Originally Posted by Bruce Abbott

Which 'RKRM' would that be, and what page do I read?

There is actually more than 1 page, but you can start here:

http://amigadev.elowar.com/read/ADCD.../node001B.html

http://amigadev.elowar.com/read/ADCD.../node033C.html

http://amigadev.elowar.com/read/ADCD.../node033B.html

Originally Posted by Bruce Abbott

Ah, I see the problem now. I had assumed that since Michael Sinz was head of the Amiga OS group and the Enforcer was provided on the official developer disks that he was speaking for Commodore.

No, he was not the head of the Amiga OS group. He was a software developer who worked a short time for Commodore, developing and debugging the 68040.library. He also took over the development of Enforcer. But the later versions of it were developed in his post Commodore days.

Originally Posted by Thomas Richter

The RKRMs predate the support of the 68040 in AmigaOs, so it is not a miracle that nothing is said about MOVE16 or 68040 (leave alone 68060) specifics. They are essentially stuck at the state of Os 2.1.

<sigh>

[Don_Adan]

I think that You are wrong. I wrote with Michael Sinz a few emails, when i was alive. He was "Senior Amiga Systems Engineer/OS Designer for Commodore-Amiga". He worked for Commodore from Amiga kick 2.0 to 3.1. Later he worked for Scala.


http://www.sinz.org/Michael.Sinz/Amiga/index.html

[SpeedGeek]

Originally Posted by Don_Adan

I think that You are wrong. I wrote with Michael Sinz a few emails, when i was alive. He was "Senior Amiga Systems Engineer/OS Designer for Commodore-Amiga". He worked for Commodore from Amiga kick 2.0 to 3.1. Later he worked for Scala.


http://www.sinz.org/Michael.Sinz/Amiga/index.html

It appears that some misunderstandings will occur when translating English to other languages. But the formal title does not put him in charge of the OS development group.

"Bryce Nesbitt managed the core OS subgroup and did an amazing job at making a very disciplined release."

You can read more about this topic here:
https://www.gregdonner.org/workbench...planation.html

BTW, Dave Haynie was the "Senior Hardware Engineer" at Commodore too, and if you read his "Definitive Buster" article you will see that he needed permission from management just to do the Rev. 11.

[Don_Adan]

Easy, if You have access to leaked Amiga OS 3.1 sources, then You can check logs for every Amiga OS module. You will be known which changes was done by every Amiga OS programmer.

[SpeedGeek]

Originally Posted by Don_Adan

Easy, if You have access to leaked Amiga OS 3.1 sources, then You can check logs for every Amiga OS module. You will be known which changes was done by every Amiga OS programmer.

Okay, thanks. I will keep that in mind the next time I need to congratulate or criticize a member of the Amiga OS development team.

Now, can we please get back on topic?

[Karlos]

Originally Posted by Don_Adan

I wrote with Michael Sinz a few emails, when i was alive.

Wow, the internet truly is amazing. I knew IPv6 really expanded the range of possible addresses but I didn't realise it did so into the afterlife