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some of you might remember I was working in a expansion port cartridge last year... I'm almost finishing my project, after some months during which I did have no time to work on. I manged to flash a rewritable flash cartridge (game cartridge with mask ROM replaced by a 29F800 16 bit Flash...

Here is a little fragment of my work on Genesis. As I already said some time ago, I'm working on a expansion cart, which boots up a BIOS ROM. I managed to boot 256Kb games. Now, I added an IDE conector, and I'm able to test read CF cards. I created a file system, and a PC software to write to...

About Pinchy's gens cart Have you seen Pinchy's DRAM cart.. I'm impressed. He's done great job with the saturn and now genesis. I wonder if anyone knows any details on the implementations. I'm trying to contact with Pinchy but he does not answer... :(

I’m tring to write a comparative between MC68000 and 65c816 performance. I always asumed that motorola’s was far more powerful than SNES CPU. But I begin to doubt. :huh According to MC68000 documentation, and 65c816 docs: For a 16 bits add with carry instruction: Register to register...

Hi I'm about to upload a web page with info about my genesis expansion port cart. But I had a problem two days ago. I'm trying to map some ports to it, to control an external device. But when I was doing debuging, my Genesis died. It was working. It was actually working when I was debugging...

I want to make a list of items for the user to choose. I have done a cursor, that you move with the direction pad, to go up and down. But I wonder how could I make the rest efficiently. I I write, let's say, 10 items in the list (that is not a problem), how can I do to refresh the items?? I...

I use the following routine to poll pad status GetPAD: clr.l d0 clr.l d1 move.b #$40,$A10003 move.b $A10003,d0 andi.b #$3F,d0 move.b #$00,$A10003 move.b $a10003,d1 andi.b #$30,d1 lsl.b #2,d1 or.b d1,d0 not.b d0...

Ok, I'm working on my expansion port cart (I'll post pictures and data soon). So far, it has a ROM mapped $000000-$03FFFF (256Kb) Now I want to map a device $040000-$3FFFFF But this I need to read and write. As I'll be using only low byte accesses, I'll do byte accesses to odd addresses...

If you do a move.W #$FF00, $200000, both /LWR and /UWR will assert, and 16 data bits will be driven. Low byte goes to $200000, and high byte goes to $200001 Ok, now, suppose you do move.W #$FF00, $200001 What happends there?? Low byte goes to $200001, and high byte goes to $200002? but how...

Hi! Back to my devcart building project, I wonder if all save-game-SRAM carts map the SRAM in the same area. If you want to make a universal cart, with SRAM support for back up save games, how should be done? I check all carts I have, and all map SRAM at $200000 Thanks!

After getting my expansion port cartridge to run perfectly, I would like to make a bigger cartridge to play backup and larger games. Flash ROM is slow when writting to it. SRAM prize is high. I heard of people proposing DRAM, as if Genesis could handle it, but I don't get this clear. DRAM...

Hello, I'm using plane B for main display, but when I added plane A I observed a strange behaivour. Window and plane A cannot overlap. Tiles on plane A over window just don't show up. But if I set windows to size 4x4 cells, and I write some text on it, even if it is longer than 4 cells, it...

I've been working on a rewritable ROM board that connects to expansion port to boot code from there at $000000 when CART isn't grounded, of course. I finally finisehd it, but it doesn't work. I connected two flash roms in parallel (8 data bits from one, 8 bits from the other), using the same...

Hello, I'm going trough some XGCC demos. I think I'm getting the point, but I wonder why sometime pointers are defined as volatile, other times as registers, other times both or neither of them. For example pointer to Genesis's control and data registers. uint *pw pw = (address of...

For console ROMs I'm used to take my fonts and palettes from binary files. I always used assembler in these kind of projects. Now I'm having a look at XGCC. As I see in some demos, all data like fonts, tiles, palette,.. must be defined as if it was to be assembled, not in pure binary format...

Hello, I'm just trying to make my first demo for Genesis. I finally decided to use XGCC. I downloaded some demos written with XGCC, but my problem for now is know how to compile all the stuff. I've got the compiler, and some other files. Sega.s and md.l I also got a demo which has a batch...

Hello, If a SegaCd is conected, and a cartridge is in, which one boots?? As far as I'm concerned, cartridge will, as it grounds /CART signal and disables expansion port?? I wonder how Sega CD Transfer Suite is used to dump a cartridge. As I just read, you have to tap the /CART pin in...

I want to build a dev cart to test roms. My first idea is to mod a original cart, take out ROM, solder 2, 8 bits flash ROM for 8Mbit (4+4). This requires lots of wires and soldering work. Do you find a better (easier) solution? Another way would be a PCB conected to expansion port. Wire...

Hello, I've already made some ROMs for NES,SNES and SMS, and would like to do something for Genesis. I use WLA for SMS and SNES, and I suppose it also works for Genesis. But, do you guys recomend another assembler for Genesis?? Thanks

Any progress here? or in the Cd burning contest?? I'm still waiting to get a logic analyzer to work on modchips, and try to make another way to boot up games. Maybe replace the BIOS would work (well, I think that it must work, with one exception : the CD board has an internal command that...