Prehistoric Isle 2 NE04LL-AES 2019 Dreamcast.

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aldair
Dreamcast Swirl
Posts: 525

Prehistoric Isle 2 NE04LL-AES 2019 Dreamcast.

Post#1 » Mon Aug 19, 2019 9:35 pm


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Ian Micheal
Developer
Posts: 2669
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Re: Prehistoric Isle 2 NE04LL-AES 2019 Dreamcast.

Post#2 » Mon Aug 19, 2019 9:42 pm

I like neo4all AES better then neo4all cd.. it's much more impressive if we was to make new prefech files pre files we could get other games working very well.. only about 15 pre files ever made you know.. you need a coders cable or a bba to make them..

the src is amazing to study KOS MMU using opengl only other MMU things are wince games
Only 23 pre files they make a huge speedup

22 one is by me
prefetch.rar
(101.98 KiB) Downloaded 135 times

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aldair
Dreamcast Swirl
Posts: 525

Re: Prehistoric Isle 2 NE04LL-AES 2019 Dreamcast.

Post#3 » Mon Aug 19, 2019 9:53 pm

Ian Micheal wrote:I like neo4all AES better then neo4all cd.. it's much more impressive if we was to make new prefech files pre files we could get other games working very well.. only about 15 pre files ever made you know.. you need a coders cable or a bba to make them..

the src is amazing to study KOS MMU using opengl only other MMU things are wince games
Only 23 pre files they make a huge speedup

22 one is by me
prefetch.rar

Link: http://slipgate.org/ports/wip/gngeo/gngeo-0.7/romrc

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Ian Micheal
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Re: Prehistoric Isle 2 NE04LL-AES 2019 Dreamcast.

Post#4 » Mon Aug 19, 2019 10:19 pm

Pre files have to be made on the dreamcast not the pc thru the bba. i dont have one anymore or i make some for you guys there SH4 mmu memory map files pre they can only be made using a coders cable or a bba to get other games working we can mod the romrc yes :) they have no pre files.
http://www.dcemu.co.uk/archive/index.php/t-15275.html
chui
December 13th, 2005, 01:44
We need help to create prefetch files for NEO4ALL/AES emulator for Dreamcast.

Download package HERE (http://chui.dcemu.co.uk/releases/neo4all_prefetch.rar) and follow next steps:


----------------------------------------------------------------------

HOW TO CREATE INITIAL NEO4ALL/AES PREFETCHS


This is a little guide about how to create initial prefetch files for NEO4ALL/AES emulator. You need a BBA or coders cable for sending prefetch information from Dreamcast to PC.
In next steps, i suppose that you have a BBA, for coders cable is very similar.

1.- Create a normal CD with NEO4ALL directory+files and put your convert ROMS (.AES) to any directory too.

2.- Run DC-TOOL loader tool under Dreamcast.

3.- Swap CD with your prepared CD (step 1).

4.- Go to GNU/Linux or Windows command line and launch binary redirecting standard output, example: 'dc-tool -x aes4all.bin > prefetch'

5.- Choose any ROM without touch emulator params.

6.- Play normally and try to avoid large presentations. When MMU cache will be full emulator will stop itself.

7.- If you had played a lot of time (>30min), go to exit option menu.

8.- Send me prefetch file (stadard output redirect): sdl_gp32@yahoo.es

9.- Also you can test your prefetch, edit prefech file and cut lines between '_MMU_HANDLE_DUMP_MEMACESS_ -------' and '-------_MMU_HANDLE_DUMP_MEMACESS_', only data without tags ..._MMU_... using wordpad.

10.- Copy cut file as prefetch/name_of_aes.pre under convertneo directory and rebuild .AES file.

----------------------------------------------------------------------


Thanks to all !

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aldair
Dreamcast Swirl
Posts: 525

Re: Prehistoric Isle 2 NE04LL-AES 2019 Dreamcast.

Post#5 » Tue Aug 20, 2019 12:02 am

Ian Micheal wrote:Pre files have to be made on the dreamcast not the pc thru the bba. i dont have one anymore or i make some for you guys there SH4 mmu memory map files pre they can only be made using a coders cable or a bba to get other games working we can mod the romrc yes :) they have no pre files.
http://www.dcemu.co.uk/archive/index.php/t-15275.html
chui
December 13th, 2005, 01:44
We need help to create prefetch files for NEO4ALL/AES emulator for Dreamcast.

Download package HERE (http://chui.dcemu.co.uk/releases/neo4all_prefetch.rar) and follow next steps:


----------------------------------------------------------------------

HOW TO CREATE INITIAL NEO4ALL/AES PREFETCHS


This is a little guide about how to create initial prefetch files for NEO4ALL/AES emulator. You need a BBA or coders cable for sending prefetch information from Dreamcast to PC.
In next steps, i suppose that you have a BBA, for coders cable is very similar.

1.- Create a normal CD with NEO4ALL directory+files and put your convert ROMS (.AES) to any directory too.

2.- Run DC-TOOL loader tool under Dreamcast.

3.- Swap CD with your prepared CD (step 1).

4.- Go to GNU/Linux or Windows command line and launch binary redirecting standard output, example: 'dc-tool -x aes4all.bin > prefetch'

5.- Choose any ROM without touch emulator params.

6.- Play normally and try to avoid large presentations. When MMU cache will be full emulator will stop itself.

7.- If you had played a lot of time (>30min), go to exit option menu.

8.- Send me prefetch file (stadard output redirect): sdl_gp32@yahoo.es

9.- Also you can test your prefetch, edit prefech file and cut lines between '_MMU_HANDLE_DUMP_MEMACESS_ -------' and '-------_MMU_HANDLE_DUMP_MEMACESS_', only data without tags ..._MMU_... using wordpad.

10.- Copy cut file as prefetch/name_of_aes.pre under convertneo directory and rebuild .AES file.

----------------------------------------------------------------------


Thanks to all !

Prefetch files were only effective for cd-r use. IDE and GDEMU works much better without the prefetch files.

User avatar
Ian Micheal
Developer
Posts: 2669
Contact:

Re: Prehistoric Isle 2 NE04LL-AES 2019 Dreamcast.

Post#6 » Tue Aug 20, 2019 4:45 am

Pre files are SH4 memory maps for MMU mode for the emulator that not wrtten for CDR use only. GDEMU is a just a CDR emulator

Thats not 100% true, it should be effective for both MMU should not care if it's CDR or not
GDEMU is only emulating a CDR or GDROM drive it Still should be limted by the same thing with out MMU ..
Why would you think that ? .. I think the GDEMU is not working with pre files.. because the software does not allow MMU page mode

On the Dreamcast the MMU is not activated by default, this means that all programs executed are done so in priviledged mode(16meg) rather than user mode. The only exception here would be games written using WinCE, operating system.(also kos using mmu mode Chui wrote the mmu mapping for aes4all)

When running in priviledged mode, the application has access to all of the memory areas(512meg of vitual memory). If an application is running in user mode, then it is limatited in what it can access.

If an applicion is running in user mode, then the MMU must be enabled. So, if the MMU is enabled, then some sort of memory mapping must be provided.
AES4ALL using MMU mode pre files are SH4 MEMORY MAPS

Without using the pre file it cant use the MMU efectively thats got nothing to do with if your using a GDEMU emulator.


The emulator is running in usermod pre empt so no pre file it has no MMU sh4 map

[list=]The SH4 CPU has a 29-bit physical memory space, so the range of addresses are 0x00000000 - 0x1FFFFFFF; thus it is capable of addressing 512 Mb of physical memory. This 512 Mb is split up into eight 64 Mb areas. Table 1 shows how the SH4 sees the physical memory.

Table 1: SH4 memory areas
Start End Area
0x00000000 0x03FFFFFF 0
0x04000000 0x07FFFFFF 1
0x08000000 0x0BFFFFFF 2
0x0C000000 0x0FFFFFFF 3
0x10000000 0x13FFFFFF 4
0x14000000 0x17FFFFFF 5
0x18000000 0x1BFFFFFF 6
0x1C000000 0x1FFFFFFF 7 (Reserved)
The Dreamcast splits this memory up thus:

Table 2: Dreamcast memory map
Start End Description Area
0x00000000
0x00200000
0x00240000 0x001FFFFF
0x0023FFFF
0x03FFFFFF Boot ROM (2 Mb)
Flash ROM (256 Kb)
System devices/Hardware registers 0
0x04000000
0x04800000 0x047FFFFF
0x07FFFFFF Video/Texture memory (8 Mb)
Unused 1
0x08000000 0x0BFFFFFF Unused 2
0x0C000000



0x0D000000 0x0CFFFFFF



0x0FFFFFFF System memory (16 Mb)
Repeated at:
0x8C000000 - 0x8CFFFFFF (MMU is enabled)
0xAC000000 - 0xAFFFFFFF (Cache is enabled)
Unused 3
0x10000000
0x10800000
0x12000000 0x107FFFFF
0x11FFFFFF
0x13FFFFFF Tile Accelerator (write only)
Texture memory (write only) I'm not sure about this one
Unused 4
0x14000000 0x17FFFFFF G2 devices 5
0x18000000 0x1BFFFFFF Unused 6
0x1C000000 0x1FFFFFFF SH4 control registers 7 (Reserved)
When looking at source code from other projects you may see registers starting at address 0xA05F8000, this may cause some confusion. As the SH4 has a 29-bit address space, the top 3 bits have specific meanings.

So, if we clear the top 3 bits we get, 0x005F8000 and as we can see from tables 1 & 2, this address is in area 0.

On the Dreamcast the MMU is not activated by default, this means that all programs executed are done so in priviledged mode rather than user mode. The only exception here would be games written using WinCE, as this is a real (yeah, right!) operating system.

When running in priviledged mode, the application has access to all of the memory areas. If an application is running in user mode, then it is limatited in what it can access.

If an applicion is running in user mode, then the MMU must be enabled. So, if the MMU is enabled, then some sort of memory mapping must be provided.
[/list]

MMU does not care if it's a Gdemu or a cdr when you dont have a pre file your not using it

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