Search found 434 matches

by ob1
Sun Apr 04, 2021 5:14 pm
Forum: Super 32X
Topic: Reset and VRES
Replies: 2
Views: 953

Re: Reset and VRES

Thank you Tmee for the answer. Moreover, Chilly Willy posted his toolchain here http://gendev.spritesmind.net/forum/viewtopic.php?f=7&t=3024, and in particular, there is the file examples/Yeti3D/platform/32X/sh2_crt0.s which states main_vres_irq: mov.l mvri_mars_adapter,r1 mov.w r0,@(0x14,r1) /* cle...
by ob1
Sat Apr 03, 2021 5:49 am
Forum: Super 32X
Topic: Reset and VRES
Replies: 2
Views: 953

Reset and VRES

Hello guys. The 32X doesn't have any reset input. It does have, though, a VRES interrupt, which is raised when the user presses the reset button on its Genesis. I am trying to make a proper reset method. I have tried to clear the register and have set PC = 0, but it doesn't seem to work (I'm testing...
by ob1
Thu Mar 25, 2021 7:43 am
Forum: Super 32X
Topic: Questions on emulating the 32X
Replies: 14
Views: 1669

Re: Questions on emulating the 32X

Hello Near, and thank you so much for your investment in this 32X emulator. If there is a wishlist, and it is still open, would you consider : - a debugger (a must. 'definitely would pay for it) - throwing DEI when DMA finishes (see bit CHCR0/1.IE and register VCRDMA0/1). It looks like no game made ...
by ob1
Thu Mar 18, 2021 6:29 am
Forum: Cartridge
Topic: Current state of Genny dev carts?
Replies: 5
Views: 3643

Re: Current state of Genny dev carts?

Thanks to themrcul who allowed me to copy paste an exchange we've had on PM : Hi Olivier, Thanks for your message. I am delighted with my x7 pro. Yes, you can send through roms from the computer to the Mega Drive through the USB port, and it is blazing fast. Therefore if you are making a game you ca...
by ob1
Sun Mar 14, 2021 8:33 am
Forum: Megadrive/Genesis
Topic: update on (palette loading problem (new to asm68K))
Replies: 2
Views: 870

Re: update on (palette loading problem (new to asm68K))

There. A bit outdated, as I wrote this forever years ago, but it could help

viewtopic.php?p=11893#p11893
by ob1
Sun Mar 14, 2021 7:25 am
Forum: Megadrive/Genesis
Topic: update on (palette loading problem (new to asm68K))
Replies: 2
Views: 870

Re: update on (palette loading problem (new to asm68K))

I think there might be an error with your header. The Genesis header is 0-100h : 68k vector exception 100-200h : Genesis header Here, it seems to me that 1. you've got instructions between the exceptions and the genesis header 2. I'm not sure the header is correctly aligned Again, you may check Sik ...
by ob1
Wed Mar 10, 2021 6:19 am
Forum: Super 32X
Topic: A Simple sprite Tutorial?
Replies: 1
Views: 597

Re: A Simple sprite Tutorial?

matthewnimmo wrote:
Tue Mar 09, 2021 11:19 pm
Is there a simple Sprite tutorial out there?
Not to my knowledge.
Plus I wouldn't expect to find it on a forum. More likely a website, like a tutorial.

NB : the 32X can't natively do sprites, it just has a frame buffer. I'd say the Hello World you're talking of is a good starting point.
by ob1
Thu Mar 04, 2021 1:08 pm
Forum: Video Display Processor
Topic: VDP 128Kb Extended VRAM mode
Replies: 44
Views: 41547

Re: VDP 128Kb Extended VRAM mode

I'm sorry ot resurrect - again - such an old topic, but I've been toying with this mode, and I have problem putting it in use. Let the code : ROM_SIZE equ $10000 GFX_CTRL equ $C00004 GFX_DATA equ $C00000 _dmaSrcDestLen: macro move.w #$9300+((\3)&$FF),GFX_CTRL move.w #$9400+((\3>>8)&$FF),GFX_CTRL mov...
by ob1
Wed Feb 24, 2021 2:07 pm
Forum: Megadrive/Genesis
Topic: palette loading problem (new to asm68K)
Replies: 1
Views: 489

Re: palette loading problem (new to asm68K)

Hello Cydeenwins.
Your code looks good, but since it states it starts at 0, I wonder if you put a valid header ...
by ob1
Tue Feb 23, 2021 4:56 pm
Forum: Super 32X
Topic: 32x "security code" reverse engineered
Replies: 26
Views: 19120

Re: 32x "security code" reverse engineered

OK I got it.
Quite new for me, but that explains a lot.
Thank you very much ^^
by ob1
Tue Feb 23, 2021 3:51 pm
Forum: Super 32X
Topic: 32x "security code" reverse engineered
Replies: 26
Views: 19120

Re: 32x "security code" reverse engineered

Hello @srg320, and thank you very much for you quick answer.
Are you telling me that the custom internal ROM ($00~$FF) is actually ... RAM ?
by ob1
Tue Feb 23, 2021 1:43 pm
Forum: Super 32X
Topic: 32x "security code" reverse engineered
Replies: 26
Views: 19120

Re: 32x "security code" reverse engineered

Sorry to relive a topic - again !, but there is one line of code that I find surprising. Just between SDER and TV Mode Check, we have move.l #$8802A2,$70 ; 21 FC 00 88 02 A2 00 70 If my 68k isn't too rusty, I translate this by "write the value 0x8802a2 ... in ROM ?!" First of all, how is it possible...
by ob1
Fri Feb 19, 2021 1:56 pm
Forum: Super 32X
Topic: Master SH2 BIOS
Replies: 12
Views: 9606

Re: Master SH2 BIOS

Sorry to resurrect such an old topic, but I thought the work I've recently done one the BIOS disassembly would be useful. Now, it compiles with asmsh /ol! DC.L resetPC ; Power-on reset PC DC.L $06040000 ;Power-on reset SP DC.L resetPC ; Manual reset PC DC.L $06040000 ;Manual reset SP DC.L ERR ;Gener...
by ob1
Mon Feb 15, 2021 6:39 am
Forum: Tools
Topic: 32x ASM
Replies: 3
Views: 8086

Re:

ob1 wrote:
Mon Mar 12, 2007 8:34 am
ASMSH adds a silly header and appends a byte to the binary. I've written this tool to fix it :
or you could, you know, use "/p"
by ob1
Thu Feb 11, 2021 2:54 pm
Forum: Super 32X
Topic: DMA DEI
Replies: 4
Views: 1357

Re: DMA DEI

Thank you. I have retrieved the DDK. Though it seems to use all the 32X resources, the SH2 DEI seems left untouched. Indeed, I found no trace of something like "MOV.*_DMAVECTORN0", _DMAVECTORN0 being the label of DMAVCR0. Plus, the only value for DMAOR I found excluded the IE bit. So, I guess it's f...