Star 1. Branches Tags. Could not load branches. Could not load tags. Latest commit. Git stats 2 commits. Failed to load latest commit information. View code. Make sure the asm6 binary is named asm and that the binary is executable and accessible in your PATH. To accomplish this, games perform a technique called Sprite 0 Hit.

Super Mario Bros instructs the PPU to render a dummy sprite behind the coin, this happens to be the first sprite drawn within the frame. After the PPU beams it, it updates its status register with a flag that denotes that the first sprite a. Meanwhile, the game is constantly checking mid-frame if the sprite 0 status has been flagged a. Furthermore, since this routine repeats indefinitely, it can be quite expensive in terms of CPU cycles to execute. On the bright side, later mappers took over this function with the use of automatic interrupts that are triggered whenever an arbitrary scan-line is hit [28] a much more efficient technique , which significantly improved the visual capabilities of Super Mario Bros 3, for instance.

This notifies the game that it can start updating the tables without tearing the picture currently displayed. Only a handful of PPU registers can be updated outside the V-Blank window [30] , which explains the ability to scroll the background layer mid-frame.

Let me now show you why this design proved to be very efficient and flexible. Some games require the main character to move vertically — thus the nametable will be set up with horizontal mirroring.

Other games need their character to move left and right, and so use vertical mirroring instead. Either type of mirroring will allow the PPU to update background tiles without the user noticing: there is plenty of space to scroll while new tiles are being rendered at a distance. But what if the character wants to move diagonally? The PPU can scroll in any direction, but without extra VRAM, the edges are forced to share the same colour palette remember that tiles are grouped in blocks. This is why some games like Super Mario Bros.

As an interesting fix : the PPU allowed developers to apply a vertical mask on top of tiles, effectively hiding part of the glitchy area. This game displays more background tiles than is strictly permitted. So how is it doing that? If we take two screen captures at different times while the display is generated, we can see that the final frame is actually composed of two different frames.

By checking which part of the screen the PPU is requesting, the mapper will redirect to one chip or the other — thus allowing more unique tiles on-screen than was originally supported [32]. Throughout my research, I came across many interesting articles that explain unusual behaviour of the PPU, so I thought in mentioning some here:.

The APU sequences audio data over five channels of audio — each one reserved for a specific waveform. The music data is found in the Program ROM. Each waveform contains different properties that can be altered to produce a specific note, sound or volume.

These five channels are continuously mixed and sent through the audio signal. Moreover, the Famicom model contains cartridge pins that send the mixed audio signal to the cartridge, so the latter can mix it with extra channels requiring extra chips [38].

Pulse waves have a very distinct beep sound that is mainly used for melody or sound effects. The APU reserves two channels for pulse waves. Each can use one of three different voices, produced by varying their pulse widths. When the game needs to play a sound effect, the accompaniment channel is switched to play the effect and then returns to accompanying. This avoids interrupting the melody during gameplay. This waveform serves as a bassline for the melody. Modifying its pitch dramatically can also produce percussion.

Noise is basically a set of random waveforms that sound like white static. One channel is allocated for it. This channel has only 32 presets available. Half 16 of these presets produce clean static , and the other half produce robotic static. Samples are recorded pieces of music that can be replayed. As you can see, samples is not limited to a single waveform, but they weight a lot more space.

The APU has one channel dedicated to samples. To program this channel, games can either stream 7-bit values which steals a lot of cycles and storage or use delta modulation to only encode the variation between the next sample and the previous one.

The delta modulation implementation in the APU only receives 1-bit values, this means games can only tell if the sample increments or decrements by 1 every time the counter kicks in. So, at the cost of fidelity, delta modulation can save games from having to stream continuous values to the APU.

Since programming this channel takes longer space and CPU cycles, games normally store small pieces like drum samples that can be played repeatedly. But throughout the lifetime of the NES, many studio have come up with clever uses of this channel. Its an old IDE hard disk that I had lying around!

You can use whatever you like as long as you can fit the electronics within the case! Good luck, and enjoy the built!

I think I'm sorta in love with you right now. But i wanted one soo badly! Reply 11 years ago on Introduction. Reply 12 years ago on Introduction. Reply 11 years ago on Step 6. I wonder it super mario bros has a small chip? Then I will have a game and hdd all in one :. I actually just finished mine. Used a cheap enclosure from a local junk shop, a new gb laptop drive, a thumb drive and a zelda cartridge from a local game store. So i can play zelda and have a map up on my laptop so i don't get lost This is great!

So keep an eye on this beauty. Remember Me? What's New? Results 1 to 16 of Thread: Nes new 72 pin connector too tight for cartridge contacts?

Thread Tools Show Printable Version. Nes new 72 pin connector too tight for cartridge contacts? I remember not even thinking about that back when my NES was brand new.

I don't think anyone else did either. What goes through my mind is who even remembers how tight the original pins where. One would expect them to loosen up after twenty or so years of settling. I think this question was answered in a similar thread not too long ago.