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Old 04 December 2017, 17:22   #101
mark_k
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Quote:
Originally Posted by JimDrew View Post
WHY do you have to disable caching for the VA2000CX? That really makes no sense (coming from someone who designed Zorro II hardware).
I think other RTG cards appear as two logical Zorro (II/III) AutoConfig boards. One logical board is in I/O space ($Exxxxx for Zorro II) for all the hardware registers, the other in "RAM space" ($200000 to $9FFFFF for ZII) for the framebuffer memory.

That's good because the Amiga hardware (or your accelerator board) always treats $Exxxxx space where the hardware registers are as uncacheable.

It seems the VA2000CX appears as one logical board in RAM space. Its hardware registers are in the first 64KB, followed by the framebuffer memory. The motherboard doesn't treat that memory space as uncacheable, so you have problems with the data cache and the board's hardware registers. E.g. with data cache enabled, program loops checking a certain register bit. Instead of actually reading the register each time, it gets the old/stale value from the data cache.

To work around that, you have to either disable the data cache globally, or mark the first 64KB of board space as uncacheable with the MMU.

Hopefully a future hardware/software revision might work as two logical Zorro boards. (That would also allow 19201080 8-bit to fit into 2MB address space. Whereas now, because of 64KB register space that doesn't fit.)
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Old 04 December 2017, 18:44   #102
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I see. I guess that makes sense then. I didn't look at how the autoconfig was setup, but you are correct - either boards were strictly in Z2 address space (as a single 64K window like the original Retina) or there were two autoconfig entries, one for registers and one for RAM.

I think it would be simple enough for Lukas to split the registers and RAM.
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Old 07 December 2017, 06:33   #103
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Question: I still use Dopus 4 (and unlikely to EVER change).
When reading a text file and having to scroll down a page, it is at an unbearable snails pace and wonder if i'm missing something in a setup somewhere or this is something thats to be fixed later, or maybe even part of the above cache issue? Can make a small youtube of it if you like, compared to my standard other Amigas, text will fly up the screen.
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Old 07 December 2017, 11:33   #104
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Nothing wrong in your setup I think, the card renders scrolling text very slowly.
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Old 07 December 2017, 17:19   #105
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Even without a hardware blitter there's probably some potential room for improvement of scrolling speed. I think the driver is written in C, and down-coding some "hot" routines to assembler (e.g. using MOVEM to "waste" less bus cycles on instruction fetches) could help a lot.

Also, with Zorro II bus bandwidth is limited to ~3.58MB/sec. Using a lower colour depth (8-bit instead of 16/24) should give faster scrolling.
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Old 08 December 2017, 15:09   #106
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I had a look at the driver code and some routines are pretty (very) unoptimised. There's a lot of room for improvement. Also, the blitter wait routine busy-waits. Reducing bus bandwidth with the same trick as the ROM WaitBlit() function could possibly help there. [That is, if blit is in progress TST.B (some_cia_address).L a couple of times before checking the blitter active register again.]

I don't know how much it's used, but the wait-for-vblank routine also busy-waits. Hopefully a future hardware rev could use an interrupt for that.

Last edited by mark_k; 08 December 2017 at 15:22.
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Old 11 December 2017, 23:50   #107
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Pardon my limited knowledge, but would it be possible to change in firmware so this card works in Zorro III mode ?
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Old 12 December 2017, 10:13   #108
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It does already support Zorro III.
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Old 12 December 2017, 10:17   #109
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Quote:
Originally Posted by attle View Post
It does already support Zorro III.
Ok, so it will run faster if that is available?

I know this ultimately depends on optimizations in the driver, but earlier post mentioned a little over 3mb/s for Zorro II, which doesn't sound like much.
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Old 12 December 2017, 10:47   #110
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Originally Posted by screemo View Post
Ok, so it will run faster if that is available?

I know this ultimately depends on optimizations in the driver, but earlier post mentioned a little over 3mb/s for Zorro II, which doesn't sound like much.
about 3.5MB/s is the maximum speed you will get out of Zorro2.

Zorro3 might get you ~10MB/s depending on the interface quality.
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Old 12 December 2017, 10:52   #111
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Originally Posted by Locutus View Post
about 3.5MB/s is the maximum speed you will get out of Zorro2.

Zorro3 might get you ~10MB/s depending on the interface quality.
I have this board in an A3000/030, and saw the slowness (also posted on first page of the support thread), especially on higher color depths.

But I guess that is still work in progress, so I hope someone will help optimize the driver code
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Old 13 December 2017, 07:49   #112
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When i first got the va2000, i had to force the card into zorro ii mode, i had alot of incompatibilities (big ram plus etc) that got fixed up, i recently realised, i don't think i changed it back to Zorro III mode, so i opned the case and looked blankly as i realised, how do i switch from zorro ii to zorro iii mode? I know i did it before .. felt like years ago, but was only 6 months ago and memory is playing games on me.

Thanks.
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Old 13 December 2017, 08:53   #113
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Quote:
Originally Posted by IvanEBC View Post
When i first got the va2000, i had to force the card into zorro ii mode, i had alot of incompatibilities (big ram plus etc) that got fixed up, i recently realised, i don't think i changed it back to Zorro III mode, so i opned the case and looked blankly as i realised, how do i switch from zorro ii to zorro iii mode? I know i did it before .. felt like years ago, but was only 6 months ago and memory is playing games on me.

Thanks.
Isn't that something the firmware in the card does automatically? - allocate itself into the appropriate memory area, etc?
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Old 13 December 2017, 12:33   #114
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Quote:
Originally Posted by screemo View Post
Isn't that something the firmware in the card does automatically? - allocate itself into the appropriate memory area, etc?
What i remember was, when i had it set as Zorro 3 mode, i had lots of issues, in zorro 2 mode, it was stable, but now the firmware has fixed all thew conflicts, i only just recalled today, oh oh, i can set it back but i have NO idea how i did it ... i can't see a jumper or anything, firmware was always installed just the same way i always have .....

Am i remembering something different?
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