Search found 1162 matches

by Oziphantom
Sat Jun 12, 2021 1:50 am
Forum: NESemdev
Topic: Handling Illegal Opcodes
Replies: 10
Views: 1200

Re: Handling Illegal Opcodes

For emulation this is the source to use https://csdb.dk/release/?id=198357
by Oziphantom
Wed Jun 09, 2021 9:17 am
Forum: SNESdev
Topic: SNES programming Videos
Replies: 55
Views: 28176

Re: SNES programming Videos

SNES video 8 - setting up DMA buffers to push your VRAM updates https://youtu.be/tXEzh3yL8nY
by Oziphantom
Tue Jun 08, 2021 6:57 am
Forum: NES Graphics
Topic: 3D graphics: Linear Algebra in neslib.h
Replies: 12
Views: 1738

Re: 3D graphics: Linear Algebra in neslib.h

the NES doesn't have a bitmap mode, so you have choose where you want a line, allocated tiles, plot the line in the tiles, and then put the tiles on the screen. If a tile already exists at the position then you add the line to the existing tile. The NES is really a bad machine to learn to do this on.
by Oziphantom
Thu Jun 03, 2021 10:02 pm
Forum: NESdev
Topic: NES dev on retro pc
Replies: 20
Views: 2209

Re: NES dev on retro pc

Squaresoft used them. Since Commodores where made in Japan, Satoru Iwata started on the Commodore PET, and made VIC-20 games for Commodore. There is a tale of then unveiling one of the computers, I think it was the VIC-20. And people where trying to dissemble the display model to try and see how the...
by Oziphantom
Thu Jun 03, 2021 8:55 am
Forum: NESdev
Topic: NES trainers
Replies: 9
Views: 1020

Re: NES trainers

yes, the SNES and NES are basically identical in this way. Only the SNES is a lot easier to find free memory on as it has a lot more resources.
by Oziphantom
Thu Jun 03, 2021 7:32 am
Forum: NESdev
Topic: NES trainers
Replies: 9
Views: 1020

Re: NES trainers

Seems there are some examples here https://github.com/patois/NESTrainers
by Oziphantom
Thu Jun 03, 2021 1:48 am
Forum: General Stuff
Topic: Becoming an FPGA Engineer
Replies: 48
Views: 5767

Re: Becoming an FPGA Engineer

on the topics of VHDL, does anybody have a good intermediate training source? I know how to make a shift register and other components, but I haven't found anything that covers best practices on putting them together, how to and when to using the timing constraint tools and other "not a trivial proj...
by Oziphantom
Thu Jun 03, 2021 12:39 am
Forum: NESdev
Topic: NES dev on retro pc
Replies: 20
Views: 2209

Re: NES dev on retro pc

I'm annoyed by the constant italics theatrics. Would it annoy Oziphantom back if I wrote Apple \\e? Its not italics is a forward slash the apple//, I'm not being dramatic Apple are being dramatic https://en.wikipedia.org/wiki/Apple_IIe#/media/File:Iie-with-manuals.jpg its how it is written by Apple...
by Oziphantom
Wed Jun 02, 2021 11:06 pm
Forum: NESdev
Topic: NES trainers
Replies: 9
Views: 1020

Re: NES trainers

Do you know how to program 6502?
by Oziphantom
Wed Jun 02, 2021 10:37 am
Forum: NESdev
Topic: NES trainers
Replies: 9
Views: 1020

Re: NES trainers

look up Action Replay/Code Shark codes, that will give you the addresses that hold things you want to train. Then use a write break point to find the code that does it. You will want to play the game and try and do everything so you can get CDL (code data log) this will help you find areas of the RO...
by Oziphantom
Wed Jun 02, 2021 8:16 am
Forum: Newbie Help Center
Topic: Creating a text box
Replies: 31
Views: 2493

Re: Creating a text box

*slaps forehead*
arithmetic basically = "multiply by 2" thus it's a mul, and a negative * a negative = positive
by Oziphantom
Wed Jun 02, 2021 1:30 am
Forum: Newbie Help Center
Topic: Intermediate 6502 Tutorials
Replies: 10
Views: 11061

Re: Intermediate 6502 Tutorials

you can only use something that incs every frame as a power of two timer. So LDA randomTimer AND #%00000001 ; every 2 frames BNE _noText AND #%00000011 ; every 4 frames BNE _noText AND #%00000111 ; every 8 frames BNE _noText etc the AND masks of the bits and then those remaining bits are only 0 1 on...
by Oziphantom
Wed Jun 02, 2021 1:19 am
Forum: Newbie Help Center
Topic: Creating a text box
Replies: 31
Views: 2493

Re: Creating a text box

Huh, is that true? I checked Rockwell's datasheet and it doesn't seem to list the instruction names, but the 6510 datasheet (and a few other older MOS documents regarding 6502) does and it's indeed called "Shift Left One Bit (Memory or Accumulator)" there. However LSR is called "Shift Right One Bit...
by Oziphantom
Wed Jun 02, 2021 12:59 am
Forum: NESdev
Topic: NES dev on retro pc
Replies: 20
Views: 2209

Re: NES dev on retro pc

An Apple // while being a corner cutting overpriced machine, is much better than a NES for doing anything other than playing games. But even then only most games. Playing ultima, wizardry et al on a NES not great. Having a keyboard really helps. When you are a programmer you don't care about fancy g...
by Oziphantom
Tue Jun 01, 2021 6:03 am
Forum: Newbie Help Center
Topic: Creating a text box
Replies: 31
Views: 2493

Re: Creating a text box

In the global sense, there is an Arithmetic shift Left as well. i.e -65 Arithmetic shift left = -2 -65 Shift left = 126 -65 Arithmetic shift right = -33 -65 Shift right = 95 However on a 6502 there is no Arithmetic operations. ASL does not stand for Arithmetic Shift Left. The opcodes name is "Shift ...