Search found 70 matches

by casprog
Tue Sep 15, 2020 9:49 pm
Forum: Newbie Help Center
Topic: Basic Bank Switch question
Replies: 2
Views: 93

Re: Basic Bank Switch question

Makes perfect sense, thank you tokumaru!
by casprog
Tue Sep 15, 2020 9:15 pm
Forum: Newbie Help Center
Topic: Basic Bank Switch question
Replies: 2
Views: 93

Basic Bank Switch question

Hi all, I've been playing around with UNROM, having 8 16KB banks. I've defined the following in the first 3 banks: ;---------------------------------------------------------------- ; program bank 0 ;---------------------------------------------------------------- .base $8000 nametable_1: .incbin "nt...
by casprog
Mon Aug 24, 2020 8:22 pm
Forum: Newbie Help Center
Topic: Strange artifact
Replies: 1
Views: 599

Re: Strange artifact

erm... in my NMI....

Code: Select all

LDA #%00011110   ; enable sprites, enable background, no clipping on left side
STA $2007
that should have been $2001

I don't know why this only showed after adding a subroutine
by casprog
Mon Aug 24, 2020 8:03 pm
Forum: Newbie Help Center
Topic: Strange artifact
Replies: 1
Views: 599

Strange artifact

Hi all, After a good break after writing my first game I've come back to work with the NES again and instantly ran into a strange issue (hoping my brain didn't reset here). What you are seeing is bare bones code. I'm just loading a nametable, nothing fancy. As soon as I try adding a subroutine, even...
by casprog
Tue Nov 26, 2019 3:59 pm
Forum: Newbie Help Center
Topic: ASM6 and multiplication
Replies: 5
Views: 3253

Re: ASM6 and multiplication

The assembler can do multiplications just fine (not just ASM6, any assembler), it's the NES with its ancient 8-bit CPU that can't. The multiplications you added there run at assembly time, meaning they'll be processed by the CPU in your PC, not the 6502 inside the NES. Run-time math (which runs on ...
by casprog
Tue Nov 26, 2019 12:08 am
Forum: Newbie Help Center
Topic: ASM6 and multiplication
Replies: 5
Views: 3253

ASM6 and multiplication

Hi all. Very noob question here, originally I was hard coding some values in my constants like so: SNAKE_SIZE_START = 4 ; how many pieces to start with SNAKE_SIZE_START_BYTES = 8 ; 2 bytes per piece SNAKE_MAX_SIZE = 14 ; max pieces SNAKE_BYTES = 28 ; each piece takes 2 bytes I tried making this more...
by casprog
Thu Nov 21, 2019 5:05 pm
Forum: Newbie Help Center
Topic: is CNROM good for an adventure game?
Replies: 22
Views: 8557

Re: is CNROM good for an adventure game?

Reading back from VRAM for collision purposes is somewhat possible, but not practical for various reasons. First there's the limited access to that memory (only during vblank), then there's the fact that the graphical representation of the level geometry doesn't always correspond to the collision p...
by casprog
Thu Nov 21, 2019 4:46 pm
Forum: General Stuff
Topic: Intermediate level tutorials
Replies: 2
Views: 4199

Re: Intermediate level tutorials

Very good resource, thank you!

EDIT::

Adding a link for others:

https://www.videogamesage.com/forum/23-develop/
by casprog
Thu Nov 21, 2019 4:21 pm
Forum: Newbie Help Center
Topic: is CNROM good for an adventure game?
Replies: 22
Views: 8557

Re: is CNROM good for an adventure game?

Very clever, this sounds like it would make lookups quite difficult though? For example, if one wanted to associate properties to a background tile (solid, instant kill, etc), I imagine first the players position would need to be converted to map space (y * width + x), then a lookup into a partitio...
by casprog
Thu Nov 21, 2019 1:22 pm
Forum: General Stuff
Topic: Intermediate level tutorials
Replies: 2
Views: 4199

Intermediate level tutorials

I began learning NES development from the Nerdy Nights tutorials like many others here. I've reached a level where I can create simple games using basic mappers using asm6. But there are still concepts and even boiler plate code that I don't quite understand. What I've found online is information th...
by casprog
Thu Nov 21, 2019 12:06 pm
Forum: Newbie Help Center
Topic: is CNROM good for an adventure game?
Replies: 22
Views: 8557

Re: is CNROM good for an adventure game?

Reading back from video memory, be it CHR ROM or the nametable in VRAM, can be done only in vertical blanking or with rendering turned all the way off. This means if you're doing terrain collision using readback, you'll have to very carefully arrange your game loop to fit all terrain reads into the...
by casprog
Thu Nov 21, 2019 11:58 am
Forum: Newbie Help Center
Topic: is CNROM good for an adventure game?
Replies: 22
Views: 8557

Re: is CNROM good for an adventure game?

Some games that use multilayer metatiles cache the part of 16x16 layer around the camera in an array in RAM. Then the collision code can check attributes of individual 16x16s. Is it possible to read from the nametable space directly and do a lookup by tile id? or is it strictly necessary to have so...
by casprog
Thu Nov 21, 2019 11:53 am
Forum: Newbie Help Center
Topic: is CNROM good for an adventure game?
Replies: 22
Views: 8557

Re: is CNROM good for an adventure game?

Maps in The Legend of Zelda for NES and Super Mario Land for Game Boy are based on repetition of entire map columns. ( Super Mario Land additionally repeats entire screens, which caused me to briefly conclude the first time I played that its WORLD 1-1 was a trap level analogous to Super Mario Bros....
by casprog
Thu Nov 21, 2019 9:49 am
Forum: Newbie Help Center
Topic: is CNROM good for an adventure game?
Replies: 22
Views: 8557

Re: is CNROM good for an adventure game?

Thanks all, your advice and guidance was very helpful.

Since I'm still pretty new I may stay away from resource tricks and use a larger mapper as suggested.

I read up a little on MMC3 and that seems to be much easier in terms of worrying about PRG ROM size.
by casprog
Thu Nov 21, 2019 1:18 am
Forum: Newbie Help Center
Topic: is CNROM good for an adventure game?
Replies: 22
Views: 8557

Re: is CNROM good for an adventure game?

I was doing some more research on creating nametables with less bytes. One method I read about was having reusable slices of rows or columns and then using these slices as modular building blocks to create a scene. So that even if you wanted to modualize 8x8 tiles, you could have say 32 bytes of dat...