Questions tagged [nes]
For questions about the different versions and products of the NES (Nintendo Entertainment System)
102 questions
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Why did the NES/FC's PPU's OAM use memory that 'decays' over time?
According to the Nesdev wiki's article on the NES/FC's PPU (https://www.nesdev.org/wiki/PPU) : "while the palette is made of static memory, OAM uses dynamic memory (which will slowly decay if the ...
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Why does Super Mario Bros (NES) preemptively clear the hidden 1UP flag before Mario hits the block?
I'm analyzing the disassembled code of Super Mario Bros. (NES) and came across some logic related to hidden 1UP mushrooms. While debugging the game alongside the code, I noticed something unexpected: ...
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What aspect of resetting a NES explains bits of game state being preserved?
I owned a Paperboy cartridge for the NES and something odd I noticed was that the random order of houses in the game stayed the same between pressing the Reset button, but were different when turning ...
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How feasibly could the NES 2A03 chip use on-cartridge audio filters like the SID audio filters as a cheaper way to extend audio capabilities?
I am well aware of the SID's wide filtering capabilities. Ranging from a low, to high, to even a bandpass filter along with added resonance manipulation support, you could bring it insanely close to ...
- 1,067
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How to insert custom code into Super Mario Bros. NES file
I have a hobby project requiring adding some code to Super Mario Bros NES file.
Specifically I want to display custom text (at least 22 letters and numbers, but more likely above 100 characters) after ...
- 181
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How did the NES's RP2A03 noise generator produce 32k bit long sequences despite only being 15 bits wide?
The NES Ricoh RP2A03 has a noise channel amongst its 5 sound channels. My sources include the NesDEV wiki: https://www.nesdev.org/wiki/APU_Noise
To quote the wiki directly,
The shift register is 15 ...
- 1,067
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Did the NES CPU save die area by omitting BCD?
The NES CPU was a copy of the 6502 with the BCD circuitry removed. As I understand it, this modification was motivated by a theory that BCD was the only part of the 6502 that was actually patented, so ...
- 65.3k
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Did any Famicom game use microphone for random seed?
So I know most common way to generate pseudo-random numbers on Famicom or NES is linear feedback shift-register.
However... It came to my mind - Famicom controller has a microphone. Did any game ever ...
- 223
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Does the Game Boy version of Tetris have any crashing problems like the NES version?
Apparently history has been made when a skilled gamer manually crashed the NES Tetris at 1511 lines
With rolling pushing NES Tetris games way longer than the original developers ever imagined it ...
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In Super Mario Bros., how can I start a simultaneous multiplayer game?
I happened to receive an old NES with Super Mario Bros.
My kids pointed out that there's a two-player mode where both Mario and Luigi play at the same time. Does anybody know how to get it going?
FWIW,...
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What could SID do that APU could not?
Two of the more famous and highly regarded sound chips in the 8-bit era were the Commodore 64's SID and the Nintendo APU. Which of the two was overall better, seems to be a matter on which there is a ...
- 65.3k
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What EPROMs should I use to make my own NES cartridges?
I want to make my own NES cartridge, but I don't know what the correct type of ROM chip would be.
I am specifically thinking about the simplest PCB that works, an NES-NROM-128 which consists of a 16 ...
- 2,212
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On my NES, the color red displays as black. What could be the cause?
I have a NES, it is working normally, but one of the game colors appears as black. In the game Mario Bros 3, the name is in black, some blocks are black and the goombas too. What can it be?
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What's so different about Super Mario Brothers World T-1 that it doesn't look like level data at all?
Youtube video here: https://youtu.be/E6qRbk5Cscw?t=1127
Most of the glitched worlds are clearly ROM fragments of world data being loaded, most of them out-of-alignment and being rather messed-up.
This ...
- 2,421
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Why did my CRT TV back in the day have such noisy RF picture on the NES when a same-age one does not today? [closed]
Back when the NES was current, I got one for my birthday. I connected it using the RF thingie to my cheap noname 14" CRT TV bought a couple of years earlier, in the late 1980s or 1990 or so.
The ...
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