Search found 60 matches

by n6
Sat Dec 02, 2006 5:41 am
Forum: NESemdev
Topic: smb sprite hit problem
Replies: 9
Views: 3214

Thank you so much for the detailed answer!
one more thing... do all this happen only when bg is enabled?
by n6
Fri Dec 01, 2006 10:04 am
Forum: NESemdev
Topic: smb sprite hit problem
Replies: 9
Views: 3214

I dont understand how the vram address is changed during rendering. is the temp vram address copied at PPU cycle 6820 and then for each tile it advance 1 is added, when its enter a new scanline (1<<12) is added, and then it of course wraps.
by n6
Wed Nov 29, 2006 3:29 pm
Forum: NESemdev
Topic: smb sprite hit problem
Replies: 9
Views: 3214

That's in VBlank? I can't say for sure whether or not that happens -- but if it does, I'm sure the game writes to $2000 again afterwards *or* writes 0 to $2006 twice afterwards (which would reset the scroll).
thanks! I used the values in control1 instead of the temp vram address
by n6
Wed Nov 29, 2006 3:02 pm
Forum: NESemdev
Topic: smb sprite hit problem
Replies: 9
Views: 3214

Yeah exactly as I thought!
In my emulator I see that 1 is written to $2000 (when mario have advanced to the next nametable) at ppu cycle ~2000...

should this never happen?

and do the sprite0-hit test care about scroll values?
by n6
Wed Nov 29, 2006 2:32 pm
Forum: NESemdev
Topic: smb sprite hit problem
Replies: 9
Views: 3214

smb sprite hit problem

Ive some problems with the sprite hit for smb... When Ive went so far so NameTable is changed to 1 (2000:1) my sprite hit test obviously failes cause it isnt anything there, ive hacked it and understood that (2000:1) always should be clear when the sprite hit test is made. I have a catch up kind of ...
by n6
Sun Nov 19, 2006 6:12 pm
Forum: NESemdev
Topic: nmi_suppression problem
Replies: 6
Views: 2794

actually I incremented clock after the read, so its 3 CPU cycles off. blarggs cpu timing test passes, and my NMI takes 7 cycles, and I take care of the extra PPU cycle that may occur if bg enabled and it is an odd frame. Do any read/writes to the PPU take extra cycles? Is my problem probably cpu opc...
by n6
Sun Nov 19, 2006 4:26 pm
Forum: NESemdev
Topic: nmi_suppression problem
Replies: 6
Views: 2794

Thanks for your answer, one ? though...
Ive changed and are now updating cycles through the opcode (instead of in the end). Now #8 of vbl-timing failes! why did it work when I updated the cycles in the end (this must have been incorrect right, since the opcode didnt do the status read at that time!)
by n6
Tue Nov 14, 2006 6:19 pm
Forum: NESemdev
Topic: nmi_suppression problem
Replies: 6
Views: 2794

nmi_suppression problem

Ive problems with the nmi_suppression test. my questions goes like this: 1. after how many PPU cycles is the actual read made in an opcode (is it same for all read opcodes) 2. My solution for test 8 in the vbl_timing was to in my "Read PPU Status" I check if ppu-clock equals to 89341 then suppress t...
by n6
Thu Sep 28, 2006 4:09 am
Forum: NESemdev
Topic: How to emulate the APU
Replies: 14
Views: 6264

But I am not going to skip samples like that. Iam going to do exactly as my PPU works. when something interesting happens update to that point.
by n6
Tue Sep 26, 2006 5:01 am
Forum: NESemdev
Topic: How to emulate the APU
Replies: 14
Views: 6264

Yeah I think i'll stick to it, mix one sample per CPU cycle would be a real performance killer
by n6
Mon Sep 25, 2006 12:21 pm
Forum: NESemdev
Topic: How to emulate the APU
Replies: 14
Views: 6264

I'vent decided yet
by n6
Mon Sep 25, 2006 11:43 am
Forum: NESemdev
Topic: How to emulate the APU
Replies: 14
Views: 6264

but do you think this is a good idea? whats the common number of writes to the APU each frame?
have anyone tried this technique, what do you think?
by n6
Mon Sep 25, 2006 10:43 am
Forum: NESemdev
Topic: How to emulate the APU
Replies: 14
Views: 6264

What about this.. The linear counter is set, I start to write until next APU tick. the next thing that happens is that it stops the channel, then ive to remove everything? I was thinking about an action buffer that put all writes and at which CPU cycle they occur in a buffer and then in the end mix ...
by n6
Mon Sep 25, 2006 1:31 am
Forum: NESemdev
Topic: How to emulate the APU
Replies: 14
Views: 6264

How to emulate the APU

I need ideas of how to emulate the APU. Since i must create the mixingbuffer myself it gets much harder. When do you mix all the audio?
Ive thinked of doing it in the end of each PPU frame but this makes it hard to keep effects and status reads accurate. any ideas?

thanks
by n6
Tue Sep 12, 2006 5:54 pm
Forum: NESemdev
Topic: problem with the even/odd frames test
Replies: 21
Views: 7289

oh its bit hard to understand..but is like this: I should check when the last instruction is executed if its overflow the 'num of cycles per frame' by only one CPU cycle, if this is true, the next opcode should be executed as well?