Search found 81 matches

by eteream
Sat Feb 06, 2010 8:11 pm
Forum: Cartridge
Topic: Some questions about cartridges...
Replies: 16
Views: 5381

Don't worry, it's done.

Thanks!
by eteream
Fri Feb 05, 2010 7:11 pm
Forum: Cartridge
Topic: Some questions about cartridges...
Replies: 16
Views: 5381

Years ago, when I made my emulator these things were taken into account in the very firsts steps, I'm surprised... The thing is that it completely depends on the way the original cartridge was designed and Mask ROMs(s) mapped, simulating mirroring might be accurate for some games but completely wron...
by eteream
Thu Feb 04, 2010 10:27 pm
Forum: Cartridge
Topic: Some questions about cartridges...
Replies: 16
Views: 5381

Chilly, I understand what you say, as the program does not access the mirrored memory, is not necessary to take this into account. BUT: Do you fully know the code? I know nothing. You can be 100% sure it's the same with mirrored memory than without it? In one hand we have a 100% sure that everything...
by eteream
Thu Feb 04, 2010 1:38 pm
Forum: Cartridge
Topic: Some questions about cartridges...
Replies: 16
Views: 5381

Chilly Willy, as long as I know mirroring in not a feature, is a side effect. in the case of writing 3MB into a 4MB EPROM you'll have $FF(if you don't program those bytes) in the last 1Mbyte, no mirroring goes on... 1 wasted Mbyte... Yes, what I will do is to double the last megabyte to simulate the...
by eteream
Wed Feb 03, 2010 6:11 pm
Forum: Cartridge
Topic: Some questions about cartridges...
Replies: 16
Views: 5381

Ok, thanks!

Just to clarify about mirror question:

Image

This is the cheapest solution, so this must go.

Note: I don't care if there are 3 roms of 1Mb each or 1x2 + 1x1 Mb each, I only want to write 3Mb in a 4Mb EPROM.
by eteream
Wed Feb 03, 2010 5:56 pm
Forum: Megadrive/Genesis
Topic: What kind of IA can use a 16bit game?
Replies: 9
Views: 4033

Well, the Genesis should be able to handle a LOT more than this. You must be doing something pretty complicated to have issues with only 40 helicopters. Can you elaborate? I agree Geny can do more. Indeed I optimized a bit the code and now it is capable of doing that (using pointers instead "[]" wh...
by eteream
Tue Feb 02, 2010 5:09 pm
Forum: Cartridge
Topic: Some questions about cartridges...
Replies: 16
Views: 5381

Some questions about cartridges...

1) How mirroring works on 3 Megabytes carts? The 4rt megabyte is a mirror of the 1st or is a mirror of the 3rd mega? I think it has to be the third... but I don't know for sure. 2) A 4-megabyte cartridge memory can save games (SRAM, flash or whatever)? How? I hope this time are more specific questio...
by eteream
Wed Jan 27, 2010 1:12 am
Forum: Megadrive/Genesis
Topic: What kind of IA can use a 16bit game?
Replies: 9
Views: 4033

Thanks KanedaFr! It really sounds interesting. I don't think it's true that all games use precalculated paths. Some do, for sure, and some use a mixture. But generally a lot of games WILL do exactly what you're trying to do. Well, I don't test it in every game. Can you give an example of non-precalc...
by eteream
Fri Jan 22, 2010 7:07 pm
Forum: Megadrive/Genesis
Topic: What kind of IA can use a 16bit game?
Replies: 9
Views: 4033

Shiru, my intention is to work with C until realy asm is needed. I only want to know what a action game is capable with several (20-40) independent things moving with an IA, idealy a maximun cota. My intention was to not underrate it, but I think that MD can't perform a A* in this situation, and as ...
by eteream
Mon Jan 18, 2010 12:47 am
Forum: Megadrive/Genesis
Topic: What kind of IA can use a 16bit game?
Replies: 9
Views: 4033

What kind of IA can use a 16bit game?

While I was trying things in my game I have found that if I use 40 like helicopter enemies that each own calculate his own path based on the location of the protagonist the scroll slows a bit. Well, it isn't optimized but, there is no colision detection yet, so I can get a map of the situation. So m...
by eteream
Thu Jan 07, 2010 4:20 pm
Forum: Video Display Processor
Topic: ¿game that updates his VDP background graphics when scroll?
Replies: 0
Views: 1169

¿game that updates his VDP background graphics when scroll?

¿ Is there a game that updates his VDP background graphics during scroll ? I'm searching a game that updates his VDP graphics memory (no plane or scroll memory) when it uses scrolling techniques. But: - Special cases, like Eggman in Sonic don't count, it should be on normal game, when scrolling. - S...
by eteream
Tue Jan 05, 2010 5:14 pm
Forum: Video Display Processor
Topic: Relationship between VDP and User/Kernel Mode?
Replies: 22
Views: 5918

This is it. Thanks!
by eteream
Tue Jan 05, 2010 1:04 pm
Forum: Video Display Processor
Topic: Relationship between VDP and User/Kernel Mode?
Replies: 22
Views: 5918

Ok, I got it. When you speak about DAC you include PCM sound in it. Z80 is more slow than it seems. All it sounds very hard.

¿Do you know if old comercial games uses PCM+FM to do sound effects+music?
by eteream
Tue Jan 05, 2010 3:58 am
Forum: Video Display Processor
Topic: Relationship between VDP and User/Kernel Mode?
Replies: 22
Views: 5918

I use VINT as a timer, and I decrement each channel's timer according to an overflow value made by adding the song's speed to a global timer. That works out well. The YM2612 also has two programmable timers that you can poll. That timers sounds interesting... As far you're going on Z80, i think you...
by eteream
Sat Jan 02, 2010 8:14 pm
Forum: Video Display Processor
Topic: Relationship between VDP and User/Kernel Mode?
Replies: 22
Views: 5918

I wrote a mini dev kit which can help you to speed up yours dev and even if you don't use it directly you can at least use it as source of informations : Of course!, I'm using it to retrieve information in a fast way. Yeaahhh! reading C is faster thant natural languaje... :shock: But I'm using main...