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I'm slowly getting into creating some of the assets for my game (8k CHR-ROM only) and I'd like to get some criticism and ideas on how to improve myself. Generally I practice with art I receive/commission or find on the internet by using them as a base for "pixelization" as far as the mugshot and the...

Two things that stood out to me:
- $2007 is the PPU_DATA register, your table makes it look like it is part of the mirorred address space.
- The iNES header is 16 bytes, not 256 (but the rest of the tutorial with the ROM addresses actually considers it 16 bytes).

For one of my stages in my game with lava at the bottom, I'd like to create a sine wave movement pattern to make things look more interesting. However, my game is small and is based on very simple cart hardware so I use the DMC for raster effects. I know that I need to do this with timed code becaus...

As far as instruction sets go, sometimes I look at the Z80 set with quite some envy. It may be slow as all hell but it sure has some clever instructions that I could really use in NES programs. For example the bit tests that can test a single bit in a register or in RAM. With the 6502 you can only c...

Minor Update: ------------- I am still working on this little project every now and then, and I have created a simple compression tool that optimizes a raw 8-bit PCM file sampled at 8 272Hz for the player. Currently the player uses a primitive 1-bit RLE compression, to make use of the MSB (since the...

It takes a miniscule amount of time to read in the grand scheme of things (even with an active DMC), and even then some games opted out for an unrolled loop and had the same code repeated 8 times. It works, and honestly my question would rather be why the designers of the Mega Drive felt that a cont...

Based on a quick look at that page I'm extremely happy that when I started out I only ever used the APU reference to do what I wanted... part of the truth was that I had already familiarized myself with most of the APU features through Famitracker so it all made sense to me.

My solution to that problem is to use a byte of $AA or $55 for the timing, so the underlying square wave should be inaudibly high at rate $F. The 1-bit fluctuations caused by this sample shouldn't be too bad.

For the record, I'm using CHR-ROM and it's not going to be backswitched... this is supposed to be a tiny game aiming high... (1-bit BNROM-register to enable 64k of PRG) I added the gradient because CHR-ROM can't be compressed anyway... for monochrome fonts it's pretty easy by leaving out the second ...

I have this issue where I would like to hide sprites behind a HUD, which is at the top of the screen. The first idea I had was disabling sprites during VBlank and enabling them from an IRQ at the bottom of the status bar. Although this would be the least CPU-intensive method possible, it could be pr...

If sampling rate is an issue, you could try the method I used to get double the normally achievable rate with DMC interrupts (8 272Hz) by sitting in the IRQ handler enough to pump out another sample right in-between two consecutive IRQ-s. It takes more CPU, but you can also spend the time after the ...

This is a project I've been doing on the side for a while now, and it's time to finally reveal it and show my current progress. MintaBOOM (the word "minta" [mintɒ] being the Hungarian word for "sample") is a new, work-in-progress music player, which aims to make it possible to play sample-based musi...

OH silly me, I was expecting some kind of pulse-like tone similar to the "periodic" mode of the SN76489 but of course the 2A03 merely moves the taps around where as the SN76489 makes the output bit the feedback bit as well as resetting the sequence any time the Noise mode/period register receives a ...

Now another interesting thing to know would be if it's possible to reliably get the same timbre every time by immediately setting the mode flag when the NES is powered on, hopefully before the LFSR receives its first clock. Losing the static would not be an issue if there's an expansion chip present...

Yes, that's exactly what I want to do. It's not as harsh though because the DMC gets the level back to zero a lot more smoothly and not another $4011 write. I could even do this and have some control over the APU2 volume by selecting to play either $00 bytes all the time or $FF and writing $3F to $4...