Search found 53 matches

by russellsprouts
Tue Mar 12, 2019 4:41 pm
Forum: NESdev
Topic: Vertically stretching picture with scrolling
Replies: 15
Views: 5562

Re: Vertically stretching picture with scrolling

That makes a lot more sense, thanks. I was trying to figure out how to use fixed pattern tables, but I didn't think about this method. So each tile would look like the attached image. Call the tile here %1000000, because that's the pattern of the 8 virtual pixels on the top half. The pattern is repe...
by russellsprouts
Tue Mar 12, 2019 3:01 pm
Forum: NESdev
Topic: Vertically stretching picture with scrolling
Replies: 15
Views: 5562

Re: Vertically stretching picture with scrolling

My idea was to make a game with a monochrome bitmap display, but make each pixel of the bitmap be 2x2 hardware pixels, to decrease memory requirements, cut down on artifacts, and let me update more of the screen at once. I would use the palette trick to make each tile cover 8x8 hardware pixels on th...
by russellsprouts
Tue Mar 12, 2019 1:07 pm
Forum: NESdev
Topic: Vertically stretching picture with scrolling
Replies: 15
Views: 5562

Re: Vertically stretching picture with scrolling

Yeah, it looks like 2006 2005 2005 2006 is the best option. It's not particularly important for my use case that the scanlines be exactly in order. I could use 2x2006 writes and ignore the contents of scanlines I can't set (ones that look like xxxxx1xx) 0 0 1 1 2 2 3 3 8 8 9 9 10 10 11 16 16 17 17 1...
by russellsprouts
Mon Mar 11, 2019 4:53 pm
Forum: NESdev
Topic: Vertically stretching picture with scrolling
Replies: 15
Views: 5562

Vertically stretching picture with scrolling

I'm wanting to stretch the picture 2x in the vertical direction. Assuming I can write during hblanks, I figured it would work to set the scroll every other scanline: scanline 0, set to y scroll to 0 0 1, set to 1 1 2, set to 2 2 ... I could do a 2006, 2005, 2005, 2006 series of writes for each of th...
by russellsprouts
Mon Dec 17, 2018 5:54 pm
Forum: Newbie Help Center
Topic: help debugging code for controller input
Replies: 16
Views: 7953

Re: help debugging code for controller input

You're on the right track with keeping the previous frame's button state. There's slightly different logic you'll need though. Here's some pseudo-code to help: if (leftButton is pressed AND leftButton was not pressed last frame): move left In code, following pubby's example, that looks like this: ; ...
by russellsprouts
Fri Oct 26, 2018 11:08 am
Forum: NESdev
Topic: Best practices for instancing?
Replies: 24
Views: 10619

Re: Best practices for instancing?

I hope that chart doesn't have mistakes -- I've referenced it a lot. The only thing I know it's missing is that both PLA and TSX set the S and Z flags.
by russellsprouts
Tue Oct 16, 2018 11:50 am
Forum: Newbie Help Center
Topic: cc65 - 32KiB PRG banks and segments
Replies: 17
Views: 6095

Re: cc65 - 32KiB PRG banks and segments

This approach solves the described problem very whell, but what to do when the banks are interdependent? You'll have to compile and link them separately, but make sure to include all object files in all builds. Even though you are generating 1 bank at a time, the linker needs to know the contents o...
by russellsprouts
Fri Oct 05, 2018 11:17 am
Forum: NESdev
Topic: Dynamically generating ld65 config files
Replies: 13
Views: 6646

Re: Dynamically generating ld65 config files

Thanks everyone for the idea of using a multistage process to right-align blocks. I had this issue in my Forth project, and I've been solving it by just reserving as many bytes as possible at the start and updating it each time I get an overflow error. It's not ideal to say the least.
by russellsprouts
Mon Sep 24, 2018 12:53 pm
Forum: NESdev
Topic: Detecting button combos / sequences
Replies: 6
Views: 4632

Re: Detecting button combos / sequences

This is similar to what Rainwarrior said, but here's some ideas from fighting games -- remember that there are multiple phases of performing a move in a fighting game. A simple way to think about it might be like this: 1. Startup -- before the hitbox for the move comes out, there is a startup animat...
by russellsprouts
Fri Jun 22, 2018 11:22 am
Forum: NESdev
Topic: Alternating name tables ($2000.0) every 8 scanlines
Replies: 30
Views: 7493

Re: Alternating name tables ($2000.0) every 8 scanlines

I've done some work with DMC IRQs to try to have arbitrary splits -- I wouldn't recommend trying this for this many scanlines. Remember that IRQs happen on their own clock, starting up to 432 cycles after you trigger them. Depending on the alignment you could waste a lot of time on many of the scanl...
by russellsprouts
Fri Apr 27, 2018 4:52 pm
Forum: Newbie Help Center
Topic: Easy way to learn to code the NES?
Replies: 15
Views: 6736

Re: Easy way to learn to code the NES?

It really depends on your previous experience. There are a lot of ways to get started. If you want to use a programming language, I'd recommend starting with this tutorial: https://nesdoug.com/2015/11/15/introduction/ It shows how to make a simple game in C, but I went from there straight to learnin...
by russellsprouts
Tue Mar 20, 2018 4:15 pm
Forum: NESdev
Topic: cc/ca65 language extension for VS Code
Replies: 3
Views: 3546

Re: cc/ca65 language extension for VS Code

This looks great! I started implementing a VSCode plugin along similar lines. I also implemented parsing of debug files to provide Intellisense features -- "Go to definition", etc. I should clean up the code and submit it as a pull request to the project.
by russellsprouts
Fri Feb 16, 2018 11:16 am
Forum: NESdev
Topic: Mesen Debugger - Feedback/Feature Requests? (2018 edition)
Replies: 197
Views: 99215

Re: Mesen Debugger - Feedback/Feature Requests? (2018 editi

I started making a VSCode extension for editing CA65 assembly code. I had syntax highlighting, hover to see the values of constants, and jump to definition implemented at least. I should dig it out and make it presentable for others to use. It parses the CC65 debug info file to provide all the infor...
by russellsprouts
Tue Feb 06, 2018 12:36 pm
Forum: NESemdev
Topic: Code review request - symbolic execution engine
Replies: 1
Views: 3004

Code review request - symbolic execution engine

I've been working on a sort-of emulator for the 6502 as part of a compiler project. Here's the github repo . It symbolically executes 6502 code. I was hoping to get more eyes on the emulator code. I've probably got some bugs in there. In the repo, emulator.h is the core of the 6502 emulation. The em...
by russellsprouts
Fri Jan 05, 2018 11:01 am
Forum: NESemdev
Topic: 3DNes
Replies: 212
Views: 196697

Re: 3DNes

I really like the inventory screen transition, and the dungeon rooms look amazing.