M68K for DC

[quzar]

By the fact that you just called it 'the new Sh4', at least i can infer that you have no actual basis for those statements other than loose conjecture of what you think things mean.

Not to say that it may not be true, its just that you arn't the one in a position to be making statements like that.

edit: damn, i posted this like an hour ago, but forgot to hit send :-X alex beat me to it =P.

[DemoniusX]

well geez sorry if I gave coders what a "FAN" of emulation would like. its true though, if a new sms plus came out I honestly wouldn't care for it.the reason is because its perfect enough for me to enjoy, I don't care for FM sound cuz sms sound has too much HIGH PITCH in it., but having played the actual sms I don't see a difference. I care if a nester version comes out because the control lag was bad and the button setup sucked for games like "track and field" or "american gladiators" not to say those are find titles but I play them now and again cuz hey, I love the gray box. Neo cd is nice if we had sound fx in it, I would be happy but like you guys say Coders want what coders want. oh well that said back to playing mega man and bass on my GBA SP.

[fox68k]

Since looks like everybody is talking about the speed of the cores, i took a moment to do a speed test. 8)

First, you have to take in account the core is not completed, and i have not done any optimization yet, so consider it as VERY PRELIMINARY, only to have a light idea about performance.

The program chosen is the following. It is a simple program to calculate prime numbers:

main MOVE.L #10,D0 ; first number to analize
cont ADD.L #1,D0
BSR prime ; jump to prime routine
CMP.B #$FF,D4 ; if D4=FFh -> prime number
BNE cont ; if not prime number, jump to next number

isprim MOVE.L D0,D5 ; result from routine to D5
CMP.L #60000,D0 ; if result is greater than 60000 exit program
BLT cont ; if not, continue

final BRA.S final


************************************************** ******************
* prime - Returns if the number is prime or not
* D0 - number to analize (parameter)
* Returns D4 equal to FFh if prime, otherwise it is not prime
************************************************** ******************

prime MOVE.L #1,D1 ; D1=1

loop ADD.L #1,D1 ; increment D1
MOVE.L D0,D3 ; move number to analize to D3
DIVU D1,D3 ; divide numbers
ASR.l #8,D3
ASR.l #8,D3
CMP.l #0,D3 ; look if remainder is equal to zero
BNE loop ; if not, continue
CMP D0,D1
SEQ D4
RTS

END

Cycle slicing sent to the "emulate" function is 400 (the longer the better because increases throughput).

I put it inside a for loop and i timed the job with the KOS function timer_ms_gettime.

The result was a roughly 100 MHz 68000 emulated CPU.

Anyway emulation speed depends upon several factors and this result could change notably in other circunstances (other instructions, other cycle slicing, etc).

I read some lines from Stef D saying it could be possible to make a Z80 emulator running at 40/50 MHz in C. I know Z80 and 68K are different, but, again, consider this info carefully to evalute performance.

Cheers.

[Hola]

So your 68 runs at 100 and stef's ran at what?

[Stef]

I believe C68K speed was ~ 50 Mhz (a bit more) ... so Fox68k ASM core seems to be 2 times faster here.
But as Fox68k mentionned, comparaison depends on severals factors (here the loop test contains a DIV instruction which eat many cycles on a 68000 CPU)... we should wait for a reals conditions test to be sure about performance... 2 times faster than C68K would be really nice

[ron]

Hi. There was a long time without pass over here. Actually I have a little bit of time more and this is my idea. ;D ;D

I need somebody Â*8) helping me porting a common ATARI ST emu to the DC. Â*;D

As I mentioned time ago, the castaway means a nice bet for porting due to the SDL implementation. All GP-32 owners are very happy running the emu with games and progs. Why can't we have a port too ?
OK the original project is here: http://castaway.sourceforge.net/st.html

And also a lot of references and docs about the Atari ST.

My Idea is: Make a port called DCaSTaway, but the most important challenge is to use the cores developed in this thread. Our team had not success because all of our were really busy, so, this is a great opportunity for a nice autum, running ATARI ST on DC with your M68K CORES.

Also there are more opensource ATARI ST emus that can be easily ported to the DC, our conclusions between HATARI, ARANYM, CASTAWAY, STonX, PacifiST, STeem, WindSTon, and others was castaway due to the SDL. Most of them uses Open68K core, thats the key of the project. I have readed that your cores can accurate 100 Mhz.

Tech DATA:

The ATARI 520 ST. CPU M68000 at 7,8336 Mhz.
RAM 512 Kb + 192 Kb ROM
Video: 640 X 400. Monochrome 320 X 200. 16 colours. 640 X 200. 4 Colours
Sound. AY-3-8910 3 Channel FM
3 1/2 " Floppy Disk Drive , 320 & 720 Kb
Expansion : Midi In / Out. Centronics, Serial, Floppy, HD, Mouse and Joystick

NAME Â* 520 / 1040 STf / STfm
MANUFACTURER Â* Atari
TYPE Â* Home Computer
ORIGIN Â* U.S.A.
YEAR Â* 1986
KEYBOARD Â* Full stroke keyboard with numeric keypad, editing keypad and 10 function keys
CPU Â* Motorola MC 68000
SPEED Â* 8 mHz
RAM Â* 512 KB (up to 4 MB)
ROM Â* 32 KB with TOS on disk / 192 KB with TOS on ROM
TEXT MODES Â* 40 or 80 chars. x 25 lines (bitmapped graphics)
GRAPHIC MODES Â* 16 colors among 512 (320 x 200) / 4 colors among 512 (640 x 200) / monochrome (640 x 400) this last mode needs a special monitor.
COLORS Â* max. 512
SOUND Â* 3 voices + 1 noise channel, 8 octaves (Yamaha YM-2149)
I/O PORTS Â* Cartridge, Midi (in, out), Centronics, RS232c, Hard Disk, Floppy disk, RGB, Joystick, mouse
BUILT IN MEDIA Â* 3.5'' disk-drive
OS Â* TOS + GEM


More info: Â* http://linuxgazette.net/issue73/arndt.html
http://www.lowendmac.com/clones/atari.html
http://www.atarimuseum.com/computers...nu/atarist.htm
http://www.atari-st.lovely.net/

THANK YOU

[ron]

ATARI ST DOCUMENTATION

http://www.atari-st.lovely.net/atari-st-docs/index.html

[quzar]

iirc 138 is already working on a port of CaSTaway.

what ever happened to the m68k core you were working on?

[ron]

The idea didn't go ahead , we had not enough time and were very busy, actually i'm impressed about the work you have done. I'm glad to see that iirc138 is working on the castaway port, anyway congratulations for maintaining this thread with lots of hours of great works and thank you .

Can you please give us more information about that port of onethirtyeight ? Your info is really appreciated

[ron]

Congratulations Stef, I know your core is just AMAZING !!!!! should be nice to have your core running on a computer emu for DC.