Re: Breakthrough for the ao486 core announced - Cache
Posted: Tue Jul 07, 2020 7:06 pm
with the "last" release, the sound spits a little (doom for example)
OPL3 in OSD?
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Breakthrough for the ao486 core announced - Cache
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Re: Breakthrough for the ao486 core announced - Cache
Posted: Tue Jul 07, 2020 7:36 pm
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 4:11 am
Yes it would boost even further.NightShadowPT wrote: ↑Tue Jul 07, 2020 12:51 amWhat does this mean? That it will be possible to implement a more efficient L1 Cache to boost performance even further? Or just that in the FPGA implementation you don't need L1 and L2 caches?bbond007 wrote: ↑Mon Jul 06, 2020 10:00 pm This is a test of the latest where FPGAzumSpass has disabled the (faulty) ao486 level 1 cache for an additional boost!
--> https://youtu.be/y9CycqjfOxY
It is still not understood why enabling the Level 1 cache hangs up the core, but in either case it was kind of a slow cache anyway with 3 cycles latency from cache request to response.
L1 cache is more difficult than L2, as it must keep coherency, but i guess at some point we get it back or a new one.
However, don't expect a huge performance gain from it.. The best that could happen is 4-5 cycles less latency.
That may lead to something like additional 30% more performance, which is nice, but not the big jump anymore.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 4:19 am
First of all, thank you for your work on this core... it's great to see it getting some love.FPGAzumSpass wrote: ↑Wed Jul 08, 2020 4:11 amYes it would boost even further.NightShadowPT wrote: ↑Tue Jul 07, 2020 12:51 amWhat does this mean? That it will be possible to implement a more efficient L1 Cache to boost performance even further? Or just that in the FPGA implementation you don't need L1 and L2 caches?bbond007 wrote: ↑Mon Jul 06, 2020 10:00 pm This is a test of the latest where FPGAzumSpass has disabled the (faulty) ao486 level 1 cache for an additional boost!
--> https://youtu.be/y9CycqjfOxY
It is still not understood why enabling the Level 1 cache hangs up the core, but in either case it was kind of a slow cache anyway with 3 cycles latency from cache request to response.
L1 cache is more difficult than L2, as it must keep coherency, but i guess at some point we get it back or a new one.
However, don't expect a huge performance gain from it.. The best that could happen is 4-5 cycles less latency.
That may lead to something like additional 30% more performance, which is nice, but not the big jump anymore.
It has been a long time since I've been so excited at the progress on a core and the potential to achieve new heights.
I would argue that 30% is still a considerable speed boost (not when you compare it to 150%, but still), putting the core speed anywhere between a 33--50Mhz 486DX, allowing most MS-DOS games to be played.
Thanks again for all your work.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 4:22 am
The good news is that as the number of total cycles per instruction goes down (for example due to L2 cache), each additional cycle of gain has an increasing percentage impact...
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 9:45 am
OPL2 or OPL3 both have no Sound Blaster music, but do have sound effects with test version 3 - to be clear the exact VHD and settings work with offical version with music and sound effects.
Here are my boot config files - maybe I have something set wrong?
autoexec.bat
Code: Select all
@ECHO OFF
set BLASTER=A220 I5 D1 T2
PATH=C:\;C:\DOS;C:\QEMM
GOTO %CONFIG%
:QEMM
C:\QEMM\LOADHI /R:2 /RES=4272 /SQT=FC00-FCFF DOSKEY
GOTO END
:QEMM_SOFTMPU
C:\QEMM\LOADHI /R:1 C:\SOFTMPU /MPU:330 /OUTPUT:COM1
C:\QEMM\LOADHI /R:2 /RES=4272 /SQT=FC00-FCFF DOSKEY
GOTO END
:QEMM_IRQ_SOFTMPU
C:\QEMM\LOADHI /R:1 C:\SOFTMPU /SB:220 /IRQ:5 /MPU:330 /OUTPUT:COM1
C:\QEMM\LOADHI /R:2 /RES=4272 /SQT=FC00-FCFF DOSKEY
GOTO END
:HIMEM
:HIMEM_EMM386
DOSKEY
:ENDCode: Select all
[MENU]
MENUITEM=HIMEM
MENUITEM=HIMEM_EMM386
MENUITEM=QEMM
MENUITEM=QEMM_SOFTMPU
MENUITEM=QEMM_IRQ_SOFTMPU
[HIMEM]
DEVICE=C:\DOS\HIMEM.SYS /TESTMEM:OFF
[HIMEM_EMM386]
DEVICE=C:\DOS\HIMEM.SYS /TESTMEM:OFF
DEVICEHIGH=C:\DOS\EMM386.EXE NOEMS X=A000-C7FF I=C800-EFFF
[QEMM]
device=c:\qemm\dosdata.sys
device=c:\qemm\qemm386.sys ram aram=c800-dfff r:1
device=c:\qemm\dos-up.sys @c:\qemm\dos-up.dat
[QEMM_SOFTMPU]
device=c:\qemm\dosdata.sys
device=c:\qemm\qemm386.sys ram aram=c800-dfff r:1
device=c:\qemm\dos-up.sys @c:\qemm\dos-up.dat
[QEMM_IRQ_SOFTMPU]
device=c:\qemm\dosdata.sys
device=c:\qemm\qemm386.sys ram aram=c800-dfff r:1
device=c:\qemm\dos-up.sys @c:\qemm\dos-up.dat
[COMMON]
DOS=HIGH
FILES=50
BUFFERS=50
LASTDRIVE=Z
DEVICE=C:\DOS\MOUSE.SYS
rem SHELL=C:\COMMAND.COM C:\ /PRe: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 10:11 am
please try these :
SET BLASTER = A220 I5 D1 H5 P330
in autoexec.bat
SET BLASTER = A220 I5 D1 H5 P330
in autoexec.bat
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 10:50 am
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 6:53 pm
Doom seems to have lost its FM sound in the version that enabled 32bit cache access, but worked with the first build with cache.
However, other games still seem to work with FM...
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 7:23 pm
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 7:40 pm
There are known bugs with the cache version and known bugs from earlier.
That's known and we work on it. (well, mainly Sorgelig)
Please use the testversions that float around with caution and only for a little preview.
That's known and we work on it. (well, mainly Sorgelig)
Please use the testversions that float around with caution and only for a little preview.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Wed Jul 08, 2020 8:24 pm
The improvement of the core is already great!FPGAzumSpass wrote: ↑Wed Jul 08, 2020 7:40 pm There are known bugs with the cache version and known bugs from earlier.
That's known and we work on it. (well, mainly Sorgelig)
Please use the testversions that float around with caution and only for a little preview.
We are not going to complain !!
Re: Breakthrough for the ao486 core announced - Cache
Posted: Thu Jul 09, 2020 9:18 am
I have the ao486_Cache2.zip running fine with sound. Anything that improves on 3 or 4 worth changing the running system?
Re: Breakthrough for the ao486 core announced - Cache
Posted: Thu Jul 09, 2020 11:10 am
Re: Breakthrough for the ao486 core announced - Cache
Posted: Thu Jul 09, 2020 12:21 pm
AS mentioned, I have sound running in Doom with ao486_Cache2.zip
Re: Breakthrough for the ao486 core announced - Cache
Posted: Thu Jul 09, 2020 1:28 pm
This is great. I hope more people keep working on PC cores and cards (VGA has still some little bugs).
I could not test ao486_Cache2.zip because it did not recognize my VHD images.
I could not test ao486_Cache2.zip because it did not recognize my VHD images.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Thu Jul 09, 2020 3:50 pm
Agreed, it's great to see the ao486 core getting updates.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Thu Jul 09, 2020 8:05 pm
I'm curious, ao486 was based on Bochs CPU C++ emulation correct? Is it C++ converted to run in VHDL? Would logic analyzing the actual CPU be better?
I was looking at an Intel project from 2006 where they programmed a Pentium in a Virtex-4 FPGA and used the FGPA as an actual chip replacement in an x86 computer and it resulted in a 27x performance boost over software implementations using very little resources. Closed source project for sure, but is that an end goal with the core? To replace that C++ cpu emulation piece by piece and create a full fledged 486 cpu in fpga?
I was looking at an Intel project from 2006 where they programmed a Pentium in a Virtex-4 FPGA and used the FGPA as an actual chip replacement in an x86 computer and it resulted in a 27x performance boost over software implementations using very little resources. Closed source project for sure, but is that an end goal with the core? To replace that C++ cpu emulation piece by piece and create a full fledged 486 cpu in fpga?
Re: Breakthrough for the ao486 core announced - Cache
Posted: Thu Jul 09, 2020 8:17 pm
To take it a step further, things like pipelines and branch prediction could be implemented to further improve the CPU implementation. Nothing says it has to exactly be a 486. It just needs to be able to run the x86 instruction set correctly and this can be improved on just like it was with 386 to 486 to Pentium, etc.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Fri Jul 10, 2020 3:04 am
In a way it's true to form, considering that back in the day there was no one single "PC" but rather a range of compatible machines made with slightly different hardware. So this would still be a "PC compatible", with its own performance optimizations, not constrained to one specific implementation (unlike consoles that are much more standardized). It's exciting to follow the development of this! 
Re: Breakthrough for the ao486 core announced - Cache
Posted: Fri Jul 10, 2020 4:41 am
@Newsdee, fully agree with you, On the other hands, even in the PC world, some computers were not 100% PC compatible like the Tandy series, the Olivetti M series etc. My favorite program that I used a lot back in the day is DESKMATE from Tandy. So far, this program does not work on the AO486 core due to graphic problems. I guess that this is due to the exotic graphic card used in the Tandy computers. Could be interesting to have the most optimized core for most of the programs/games and some option to downgrade it to match with PC8088 & Tandy 1000 for instance. It will be a dream for me aslo to have the implementation of the Hercule/MDA card. I expect too much I know Anyway as you said, this is very exciting to follow this development and the amazing huge work which has been doing on this core. AO486 is one of the reasons for which I bought the Mister and thanks to the developer, already at this stage, I do not regret it.
Anyway as you said, this is very exciting to follow this development and the amazing huge work which has been doing on this core. AO486 is one of the reasons for which I bought the Mister and thanks to the developer, already at this stage, I do not regret it.Re: Breakthrough for the ao486 core announced - Cache
Posted: Fri Jul 10, 2020 6:30 am
While GeoWorks Ensemble works on the AO486 core.. yea there are some graphical glitches that need to be addressed .. im sure its similar issues to the other posts where people talk about VGA problems .. GeoWorks was not a really "radical" application (it was a GUI alternative to Windows) .. As its an outdated productivity program I haven't really posted a lot about the visual problems, but since someone previously mentioned some issues with VGA I just thought I would throw it out there for anyone interested.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Sat Jul 11, 2020 2:09 pm
That would be awesome, I dream about something like that. But developers will have to add several Graphic cards and cpus for that to work, (and several system speeds). In the end I guess it will be easier to keep this core to be a 386/486 core, and create another for slower machines like tandy or others (8088/8086/286 cpu).
Re: Breakthrough for the ao486 core announced - Cache
Posted: Sun Jul 12, 2020 12:54 am
Will there be a way to disable the cache if needed? (to make games like Wing Commander 1 run at the proper speed?)
Re: Breakthrough for the ao486 core announced - Cache
Posted: Sun Jul 12, 2020 2:52 am
Maybe not exactly disable the cache, but they are looking at options for different speed settings.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Sun Jul 12, 2020 2:53 am
And it keeps on going... 3X the performance. Wow!
Seems a new L1 Cache is being implemented.
Seems a new L1 Cache is being implemented.
- EcqzmzzWAAIrKR7.png (145.6 KiB) Viewed 11023 times
Re: Breakthrough for the ao486 core announced - Cache
Posted: Sun Jul 12, 2020 4:00 am
So, as a last recourse, I'm posting here.
The core will not recognize VHDs regardless of what I do. It will boot from a floppy, but it will not read a VHD no matter what I try. I've gone as far as checking with inotify if the files are being accessed, and they are. I'm out of ideas, obviously I'm doing something wrong.
The core will not recognize VHDs regardless of what I do. It will boot from a floppy, but it will not read a VHD no matter what I try. I've gone as far as checking with inotify if the files are being accessed, and they are. I'm out of ideas, obviously I'm doing something wrong.
Re: Breakthrough for the ao486 core announced - Cache
Posted: Sun Jul 12, 2020 7:19 am
How about telling us how you created the vhd? Mbr or gpt?
Re: Breakthrough for the ao486 core announced - Cache
Posted: Sun Jul 12, 2020 7:39 am
hwinfo 6.1.1 doesn't run on ao486 core (fatal error)
in the status bar "Check Potomac"
in the status bar "Check Potomac"
Re: Breakthrough for the ao486 core announced - Cache
Posted: Sun Jul 12, 2020 8:49 am
Which version of the Core are you referring to as the L1 Cache version? Is it the ao486_Cache4.zip ?NightShadowPT wrote: ↑Sun Jul 12, 2020 2:53 am And it keeps on going... 3X the performance. Wow!
Seems a new L1 Cache is being implemented.
Thanks!