Search found 38 matches

by iOSBrett
Tue Jan 29, 2019 7:39 pm
Forum: NESemdev
Topic: Thank You and Reflections on Implementing a Basic NES Emu
Replies: 3
Views: 6330

Re: Thank You and Reflections on Implementing a Basic NES Em

- Most importantly don't be afraid to come to this forum to get help. If I hadn't formed a kind of camaraderie here with another user, @iOSBrett, who was about at the same stage on his Mac based emulator as I was, I probably would've never felt inspired to finish the project. Right back at you Dave...
by iOSBrett
Fri Jan 18, 2019 9:16 pm
Forum: NESemdev
Topic: Donkey Kong Score Going the Wrong Way in Demo
Replies: 9
Views: 6380

Re: Donkey Kong Score Going the Wrong Way in Demo

I had so much trouble with SDC that I ended up copying a line of code from someone else's emulator to make it work. Not my proudest moment, I have attributed the line in my source code, but still.
by iOSBrett
Fri Jan 18, 2019 9:13 pm
Forum: NESemdev
Topic: Donkey Kong Score Going the Wrong Way in Demo
Replies: 9
Views: 6380

Re: Donkey Kong Score Going the Wrong Way in Demo

If you still need the Donkey Kong annotated disassembly then you can find it at the below link. I used it a lot when trying to work out the bugs in my PPU.

https://www.romhacking.net/documents/540/
by iOSBrett
Sun Dec 30, 2018 7:30 pm
Forum: NESemdev
Topic: Giant VR NES! :D
Replies: 4
Views: 6738

Re: Giant VR NES! :D

That is VERY cool man!!!
by iOSBrett
Thu Dec 27, 2018 7:16 pm
Forum: NESemdev
Topic: All my backgrounds are grey
Replies: 5
Views: 5131

Re: All my backgrounds are grey

From reading the wiki I thought that I wasn't supposed to be reading from the addresses at 3F00, 3F04, 3F08, 3F12 and using background color instead. But re-reading that again, it does not include 3F00. Instead I should be reading from 3F00 when reading from 3F04, 3F08, and 3F12. Bingo!!! Just as I ...
by iOSBrett
Thu Dec 27, 2018 4:59 am
Forum: NESemdev
Topic: All my backgrounds are grey
Replies: 5
Views: 5131

Re: All my backgrounds are grey

It does work, so I think this is what I am supposed to be doing, thanks @lidnariq
by iOSBrett
Thu Dec 27, 2018 4:44 am
Forum: NESemdev
Topic: All my backgrounds are grey
Replies: 5
Views: 5131

Re: All my backgrounds are grey

@lidnariq I am intentionally doing that though, my code is wrong because my understanding of this part is wrong. I am returning zero because my understanding is that anything in addresses 3F00, 3F04, 3F08, and 3F12 is a transparent pixel and is supposed to be drawn in the background color below a sp...
by iOSBrett
Thu Dec 27, 2018 1:01 am
Forum: NESemdev
Topic: All my backgrounds are grey
Replies: 5
Views: 5131

All my backgrounds are grey

Hi, I was implementing sprite priority and testing Balloon Fight and found that the sprite for the Balloon in the title screen is behind the background. So it didn't show up in my emulator. So I implemented transparency for backgrounds the same as I had in sprites. ie anything at palette addresses 3...
by iOSBrett
Mon Dec 24, 2018 1:08 am
Forum: NESemdev
Topic: PPU sprite evaluation question
Replies: 10
Views: 8306

Re: PPU sprite evaluation question

Also, be warned that some games will sometimes show a sprite in the top left corner of the screen. This does not mean that your emulator is wrong. I think that 'Pacman' does it on the title screen. Oh I never knew that, thanks for the heads up. Also, some games like 'Pinball' will use the backgroun...
by iOSBrett
Sat Dec 22, 2018 7:40 pm
Forum: NESemdev
Topic: PPU sprite evaluation question
Replies: 10
Views: 8306

Re: PPU sprite evaluation question

Thats for sprite overflow right WedNESday?

Have actually made quick progress on the sprites once I decided to do it the quick an dirty way, everything calculated once in horizontal blank.
Still lots of stuff to fix and implement, but am happy with where I am so far.
Sprites.png
by iOSBrett
Fri Dec 21, 2018 10:22 pm
Forum: NESemdev
Topic: PPU sprite evaluation question
Replies: 10
Views: 8306

Re: PPU sprite evaluation question

Ahh got it *slaps forehead*

Thanks tepples
by iOSBrett
Fri Dec 21, 2018 10:14 pm
Forum: NESemdev
Topic: PPU sprite evaluation question
Replies: 10
Views: 8306

Re: PPU sprite evaluation question

Sorry, it still doesn't make sense to me, what does Secondary OAM look like with some in range sprites and some not in range sprites? How do we read it back if some bytes are only Y values and some are the full 4 values (X, Y, Tile, Attributes). secondaryOAM[0] = Y secondaryOAM[1] = index secondaryO...
by iOSBrett
Fri Dec 21, 2018 9:59 pm
Forum: NESemdev
Topic: PPU sprite evaluation question
Replies: 10
Views: 8306

Re: PPU sprite evaluation question

But won't secondary OAM be full after checking the first 8 sprites?
by iOSBrett
Fri Dec 21, 2018 9:39 pm
Forum: NESemdev
Topic: PPU sprite evaluation question
Replies: 10
Views: 8306

PPU sprite evaluation question

From the Wiki on PPU sprite evaluation Cycles 65-256: Sprite evaluation On odd cycles, data is read from (primary) OAM On even cycles, data is written to secondary OAM (unless secondary OAM is full, in which case it will read the value in secondary OAM instead) 1. Starting at n = 0, read a sprite's ...
by iOSBrett
Thu Dec 20, 2018 12:59 am
Forum: NESemdev
Topic: Stuck with PPU emulation (Donkey Kong)
Replies: 31
Views: 33465

Re: Stuck with PPU emulation (Donkey Kong)

All Background rendering normal, finally!

Thanks for everyones help.

@davecom I have caught up to you, time for us to tackle Sprites!
DKWorking1.png
DKWorking2.png
DKWorking3.png
DKWorking4.png