Problematic Demos. - Page 26

StingRay · 23 December 2013, 14:30

Quote:

Originally Posted by Toni Wilen

I finally found the real reason, very early part (landscape that has the blitter bug that prevented it from working for years..) corrupts one word in music pattern data. I know how to fix it but it isn't simple fix.

That sounds like an interesting bug, out of curiosity, how come this doesn't happen on a real Amiga?

Toni Wilen · 23 December 2013, 14:55

Quote:

Originally Posted by StingRay

That sounds like an interesting bug, out of curiosity, how come this doesn't happen on a real Amiga?

"First" bug: http://eab.abime.net/showpost.php?p=579713&postcount=17 (Lots of demos do accidental blitter register modifications while it is active but this is probably the only that self-destructs if it isn't emulated exactly. All others simply have some random graphics garbage)

Second bug is even trickier, D channel starts from $40A40, then D channel pointer is changed to 0 (move.l #0,$dff054) and because 68000 is 16-bit, high word is cleared first and D becomes 00000Axx temporarily and blitter uses this address for one D write (because cycle mode is -D-D-D), after the D-write low word gets cleared too.

Of course this does not happen on real hardware and reason is most likely already known Agnus DMA feature, DMA fetch exactly 1 cycle after channel's DMA pointer modification gets either ignored or DMA uses old address and new address become valid after DMA fetch. (EDIT: also high and low address pointers seem to work slightly differently, this needs confirmation first)

Bitplane and sprite pointers have similar behavior and there are demos that only work correctly if write is ignored..

This also explains why there is no same channel DMA fetches back to back, Agnus probably has some kind of 2 stage pipeline for DMA accesses.

EDIT: Confirmed. Write goes nowhere, both low and high address writes are totally ignored by Agnus. This actually means there are two blitter side-effects that both "protects" this demo from crashing. Write to DPTL or DPTH: nothing happens, blitter keeps writing to original address, no self-destruct. Then write to BLTCON0 stops the blitter from doing D writes at all.

amilo3438 · 23 December 2013, 16:02

Continuation from:
http://eab.abime.net/showpost.php?p=...&postcount=496
http://eab.abime.net/showpost.php?p=...&postcount=497

A Small Intro (Intro) by Tww

A500 OCS/ECS (most common) ... strange, as on the link picture it looks different ... pic.1 !!!

Toni Wilen · 23 December 2013, 17:02

Quote:

Originally Posted by amilo3438

Copper Intro (Intro) by Tracheen

A500 OCS/ECS KS1.2/1.3 ... glitches ... pic.1 !!!

Another BBS Intro (Intro) by Tragedy

A500 OCS/ECS ... Exception 3 !!!

Rebirth (Demo) by Tribe

A500 OCS/ECS ... most likely CPU timing -> pic.2 !!! (Note: It doesnt happen if 68020 is used, but anyway -> how it behaves on a real ECS Amiga ?!)

Axes High (Demo) by Triflex & Bad

A500 OCS/ECS ... pic.3 !!!

The End (Demo) by Trilobit & Flo

A500 ECS 1mb ... just wondering, does the glitches on scrolltext appears also on a real Amiga ... pic.4 ?!

Anti-Consider-Demo (Intro) by Triplex

This is a joke, right ?!

Multipart Demo (Demo) by Tronix

A500 OCS/ECS (most common) ... strange lines before scrolling text ... pic.5 !!!

All A500 confirmed.

Toni Wilen · 23 December 2013, 18:42

Quote:

Originally Posted by amilo3438

Work For Nothing (Demo) by Turnips

A500 ECS 1mb ... some glitches pic.1, pic.2 , and strange line pic.3 !!!
(Note: It happens the same also on AGA 1200 ... hm, maybe the dms is damaged ?!)

A500 confirmed. Yeah, most likely damaged file.

Quote:

Psycho Medium 4 (Intro) by Turnips

A500 ECS ... glitches ... pic.4 !!!

This is emulation bug, copper emulation timing is wrong (it is too slow in this situation). Needs some logic analyzer testing..

EDIT: It is caused by weird copper feature, special/dummy copjmp second cycle disappears if it would cross scanlines (=it would be positioned immediately after first strobe/refresh slot)

Quote:

Lotus Esprit Turbo Challenge 2 (Crack Intro) by Two Live Crew

A500 OCS/ECS ... BLITTER issue or not ?! ... pic.5 !!!

It is.

Quote:

Originally Posted by amilo3438

Continuation from:
http://eab.abime.net/showpost.php?p=...&postcount=496
http://eab.abime.net/showpost.php?p=...&postcount=497

A Small Intro (Intro) by Tww

A500 OCS/ECS (most common) ... strange, as on the link picture it looks different ... pic.1 !!!

It does not set color register number 15 and apparently it is full white after power up, at least if Denise is ECS version. A1000 (8362R6 Denise) shows it as black so A500 OCS Denise most likely does the same. (Color registers are inside Denise chip)

It is demo bug, chipset register contents after power up are not be guaranteed, but I still "fix" it.

Of course color is also wrong if any program, for example demo pack menu is run and it uses color 15.

amilo3438 · 23 December 2013, 19:29

JFI: Interesting, on MSVC 2013 SSE2 version no problem -> http://eab.abime.net/showpost.php?p=...&postcount=499

Bliss-Out (Demo) by Ukonx

A500 ECS 1mb ... pic.1 !!!

Digital Stagnation (Demo) by United Lamers

A500 OCS/ECS (most common) ... on demo part called - see pic.2 - something strange appear - see pic.3 !!!

Megademo (Megademo) by United Lamers

A500 OCS/ECS (most common) ... a little strange: F1 part1 ... pic.4 ?!

Roxette (Demo) by United Lamers

A500 OCS/ECS (most common) ... pic.5 !!!

amilo3438 · 24 December 2013, 00:54

FYI ... Hi Freaks (Intro) by Supplex & The Silents -> http://eab.abime.net/showpost.php?p=...&postcount=184

Just noticed on latest (todays) winuae.zip the above demo problem returned back ... the last version where it was working fine is winuae.zip 2013-12-21 15:12 !!!

Toni Wilen · 24 December 2013, 09:01

Quote:

Originally Posted by amilo3438

FYI ... Hi Freaks (Intro) by Supplex & The Silents -> http://eab.abime.net/showpost.php?p=...&postcount=184

Just noticed on latest (todays) winuae.zip the above demo problem returned back ... the last version where it was working fine is winuae.zip 2013-12-21 15:12 !!!

Should work again (but it had nothing to do with recent changes, they only showed yet another older problem)

Quote:

Its a little strange, but official is compiled with VC10 and test version VC 13, right ?! ... maybe something there causing the problem !!!

This can wait until real beta comes which will use heavier optimization settings.

Quote:

Originally Posted by amilo3438

And also from Demos with "most likely CPU emulator timing" issues:
Rampage (Trackmo) by The Electronic Knights ... the music doesnt missing now on "naked lady" part !!!

This is now fully fixed. (Remember that corruption happens when "landscape" part starts, do not attempt to test it by loading statefile saved later)

Toni Wilen · 24 December 2013, 10:22

EDIT: Turnips-PsychoMedium4 now works better but left side of the box is wrong.

Quote:

Originally Posted by amilo3438

JBliss-Out (Demo) by Ukonx

A500 ECS 1mb ... pic.1 !!!

A500 confirmed. (I'd really like to say something about technical quality of this demo but it is christmas

)

Quote:

Digital Stagnation (Demo) by United Lamers

A500 OCS/ECS (most common) ... on demo part called - see pic.2 - something strange appear - see pic.3 !!!

Confirmed.

Quote:

Megademo (Megademo) by United Lamers

A500 OCS/ECS (most common) ... a little strange: F1 part1 ... pic.4 ?!

Confirmed.

Quote:

Roxette (Demo) by United Lamers

A500 OCS/ECS (most common) ... pic.5 !!!

And again confirmed. (All other glitches in above 3 also matches..)

1time · 24 December 2013, 11:31

Toni: Your work is amazing! Merry Christmas.

amilo3438 · 24 December 2013, 12:35

Quote:

Originally Posted by Toni Wilen

This is now fully fixed. (Remember that corruption happens when "landscape" part starts, do not attempt to test it by loading statefile saved later)

Fully fixed, confirmed ... so it was a blitter and not a cpu timing issue.

Now only one problem remains in "most likely CPU emulator timing" issues ... thats really great !!!

Quote:

Originally Posted by Toni Wilen

EDIT: Turnips-PsychoMedium4 now works better but left side of the box is wrong.

Yes, I also now noticed on left side box something is wrong.

p.s. Hope will manage to finish verifying all planed demos/intros for this year (now only letters V,W,X,Y,Z remains) ... so will continue for two days.

Merry Christmas !!!

EDIT:
To Moderator,
it is reached character limit on page 1 post 2 ... could be created another empty page 3 below page 2 to continue with updating. TIA

amilo3438 · 24 December 2013, 19:59

Just noticed that from "Demos with "sprite related" issues":

Laurent & Anna (Demo) by Saturne & Trilogy -> http://eab.abime.net/showpost.php?p=...&postcount=384

no anymore vertical line appears in middle of the screen ... hm, does this has been fixed or it happens by accident ?!

(p.s. It seems to be "fixed" from winuae.zip test version 2013-12-15.)

EDIT:
It applies also for "Demos with "scanline emulation optimization" issues":

Blue Venture (Demo) by Anxious -> http://eab.abime.net/showpost.php?p=...&postcount=400

(p.s. It seems to be "fixed" from winuae.zip test version 2013-12-22.)

But cant find anywhere written confirmation that above 2 demos has really been fixed or that is a side effect from some other fix.

prowler · 25 December 2013, 00:55

Quote:

Originally Posted by amilo3438

To Moderator,
it is reached character limit on page 1 post 2 ... could be created another empty page 3 below page 2 to continue with updating. TIA

@amilo3438: I have inserted a blank post #3 in the thread following the first two posts for you to continue adding links.

Toni Wilen · 25 December 2013, 19:03

Quote:

Originally Posted by amilo3438

But cant find anywhere written confirmation that above 2 demos has really been fixed or that is a side effect from some other fix.

It does not need confirmation, if it works now, it is fixed (related problem) or something else hide the problem. Looking for possible hidden problems from working programs is not worth the trouble

amilo3438 · 25 December 2013, 20:07

Yeah, now look and work good so no need for fixing anything.

P.s. There is one motto ... If it aint broke, don't fix it.

amilo3438 · 26 December 2013, 19:23

Conformism (Trackmo) by Vega

A500 ECS (most common) ... part title screen (pic.1) -> some holes on a dots flag screen -> pic.2 !!!

First Intro (Demo) by Violent Wave

A500 OCS/ECS (most common) ... dash & dots ... pic.3 !!!

Instant Thing (Intro) by Visdom

A500 OCS/ECS (most common) ... scrolltext twitching on ECS !!!

Vertical Pulse (Demo) by Visdom

A500 OCS/ECS (most common) ... pic.4 !!!

Ace Ball (Crack Intro) by Wanted Team

A500 OCS/ECS (most common) ... rotating cube occasionally disappears from screen in CE mode !!! (It doesnt happen if CE=OFF.)

First Attempt (Demo) by Wave

A500 OCS/ECS (most common) ... end scroller ... pic.5 !!!

amilo3438 · 27 December 2013, 14:42

First Intro (Intro) by Weird Science 2662

A500 OCS KS1.2/1.3 512 chip ... red dash ... pic.1 !!!

Aegis Sonix v1.3 - import (Crack Intro) by Wizards

A500 OCS KS1.2 512 chip ... it doesnt work ?! (Note: Its released 1987.)

Toni Wilen · 27 December 2013, 17:59

Quote:

Originally Posted by Toni Wilen

EDIT: Turnips-PsychoMedium4 now works better but left side of the box is wrong.

Fully fixed. (But it could break other programs, I tested few demos that use similar horizontal scaling method and they still worked)

This was really good test case. There is small delay before BPLCON1 write and before output changes. Image is correct only if delay is exactly right.

Toni Wilen · 27 December 2013, 18:31

Quote:

Originally Posted by amilo3438

First Intro (Intro) by Weird Science 2662

A500 OCS KS1.2/1.3 512 chip ... red dash ... pic.1 !!!

A500 and A1000 confirmed.

Quote:

Aegis Sonix v1.3 - import (Crack Intro) by Wizards

A500 OCS KS1.2 512 chip ... it doesnt work ?! (Note: Its released 1987.)

KS 1.1 only! This is how it replaces system copper list:

Code:

MOVE.L #my_copper_list,$000025c0

(Apparently opening graphics.library is too work)

Toni Wilen · 27 December 2013, 20:02

Quote:

Originally Posted by amilo3438

Conformism (Trackmo) by Vega

A500 ECS (most common) ... part title screen (pic.1) -> some holes on a dots flag screen -> pic.2 !!!

A500 confirmed.

Quote:

First Intro (Demo) by Violent Wave

A500 OCS/ECS (most common) ... dash & dots ... pic.3 !!!

A500 confirmed.

Quote:

Instant Thing (Intro) by Visdom

A500 OCS/ECS (most common) ... scrolltext twitching on ECS !!!

A500 confirmed. Sets ECS-only display position bits as usual.

Quote:

Vertical Pulse (Demo) by Visdom

A500 OCS/ECS (most common) ... pic.4 !!!

A500 confirmed.

Quote:

Ace Ball (Crack Intro) by Wanted Team

A500 OCS/ECS (most common) ... rotating cube occasionally disappears from screen in CE mode !!! (It doesnt happen if CE=OFF.)

Flickering and other glitches A500 confirmed. Probably never tested with A500.

Quote:

First Attempt
(Demo) by Wave

A500 OCS/ECS (most common) ... end scroller ... pic.5 !!!

A500 confirmed.

I think I can finally say that chipset and 68000 CPU is now practically 100% (minus stupid bugs) cycle-exact and biggest remaining problems are: blitter register modifications while active and reading write-only registers that isn't correctly emulated yet.

Thanks for finding HUGE amounts of test cases (the more there is similar test cases, the easier it is to solve).

(Of course next problem you find is something unexpected..)

23 December 2013, 16:02	#503
amilo3438 Amiga 500 User Join Date: Jun 2013 Location: EU Posts: 1,502	Continuation from: http://eab.abime.net/showpost.php?p=...&postcount=496 http://eab.abime.net/showpost.php?p=...&postcount=497 A Small Intro (Intro) by Tww A500 OCS/ECS (most common) ... strange, as on the link picture it looks different ... pic.1 !!! Attached Thumbnails Last edited by amilo3438; 23 December 2013 at 16:13.

23 December 2013, 19:29	#506
amilo3438 Amiga 500 User Join Date: Jun 2013 Location: EU Posts: 1,502	JFI: Interesting, on MSVC 2013 SSE2 version no problem -> http://eab.abime.net/showpost.php?p=...&postcount=499 Bliss-Out (Demo) by Ukonx A500 ECS 1mb ... pic.1 !!! Digital Stagnation (Demo) by United Lamers A500 OCS/ECS (most common) ... on demo part called - see pic.2 - something strange appear - see pic.3 !!! Megademo (Megademo) by United Lamers A500 OCS/ECS (most common) ... a little strange: F1 part1 ... pic.4 ?! Roxette (Demo) by United Lamers A500 OCS/ECS (most common) ... pic.5 !!! Attached Thumbnails Last edited by amilo3438; 23 December 2013 at 21:56.

24 December 2013, 19:59	#512
amilo3438 Amiga 500 User Join Date: Jun 2013 Location: EU Posts: 1,502	Just noticed that from "Demos with "sprite related" issues": Laurent & Anna (Demo) by Saturne & Trilogy -> http://eab.abime.net/showpost.php?p=...&postcount=384 no anymore vertical line appears in middle of the screen ... hm, does this has been fixed or it happens by accident ?! (p.s. It seems to be "fixed" from winuae.zip test version 2013-12-15.) EDIT: It applies also for "Demos with "scanline emulation optimization" issues": Blue Venture (Demo) by Anxious -> http://eab.abime.net/showpost.php?p=...&postcount=400 (p.s. It seems to be "fixed" from winuae.zip test version 2013-12-22.) But cant find anywhere written confirmation that above 2 demos has really been fixed or that is a side effect from some other fix. Last edited by amilo3438; 24 December 2013 at 20:18.

25 December 2013, 20:07	#515
amilo3438 Amiga 500 User Join Date: Jun 2013 Location: EU Posts: 1,502	Yeah, now look and work good so no need for fixing anything. P.s. There is one motto ... If it aint broke, don't fix it. Last edited by amilo3438; 25 December 2013 at 20:31.

26 December 2013, 19:23	#516
amilo3438 Amiga 500 User Join Date: Jun 2013 Location: EU Posts: 1,502	Conformism (Trackmo) by Vega A500 ECS (most common) ... part title screen (pic.1) -> some holes on a dots flag screen -> pic.2 !!! First Intro (Demo) by Violent Wave A500 OCS/ECS (most common) ... dash & dots ... pic.3 !!! Instant Thing (Intro) by Visdom A500 OCS/ECS (most common) ... scrolltext twitching on ECS !!! Vertical Pulse (Demo) by Visdom A500 OCS/ECS (most common) ... pic.4 !!! Ace Ball (Crack Intro) by Wanted Team A500 OCS/ECS (most common) ... rotating cube occasionally disappears from screen in CE mode !!! (It doesnt happen if CE=OFF.) First Attempt (Demo) by Wave A500 OCS/ECS (most common) ... end scroller ... pic.5 !!! Attached Thumbnails Last edited by amilo3438; 27 December 2013 at 14:17.

24 December 2013, 00:54	#507
amilo3438 Amiga 500 User Join Date: Jun 2013 Location: EU Posts: 1,502	FYI ... Hi Freaks (Intro) by Supplex & The Silents -> http://eab.abime.net/showpost.php?p=...&postcount=184 Just noticed on latest (todays) winuae.zip the above demo problem returned back ... the last version where it was working fine is winuae.zip 2013-12-21 15:12 !!!

24 December 2013, 11:31	#510
1time Amiga Lover Join Date: Jan 2010 Location: Stockholm / Sweden Age: 46 Posts: 612	Toni: Your work is amazing! Merry Christmas.

27 December 2013, 14:42	#517
amilo3438 Amiga 500 User Join Date: Jun 2013 Location: EU Posts: 1,502	First Intro (Intro) by Weird Science 2662 A500 OCS KS1.2/1.3 512 chip ... red dash ... pic.1 !!! Aegis Sonix v1.3 - import (Crack Intro) by Wizards A500 OCS KS1.2 512 chip ... it doesnt work ?! (Note: Its released 1987.) Attached Thumbnails Last edited by amilo3438; 27 December 2013 at 16:11.

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