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OffTopic > NES MIDI interface :)

#620 - Burre - Thu Jan 09, 2003 12:56 am

Yesterday I spent some time sorting some of my old bookmarks when found one that I had almost forgot. It was a bookmark to the www.sidstation.com page (an synthmodule based on MOS6581 and developed by a Swedish company namned Electron). Anyway, as much as I would want one, the price tag always scares me off (5400 SEK). So I thought to my self, well all old consoles have soundchips in them, why not utilise the chip inside the console and just biuld an interface and code a program? Since I don't have a Commondore I looked at my old consoles and thought that the NES would probably be a good plattform. I started searching the net to see if anything like it have been manufactured earlier. Found nothing for the NES but discovered that some had done an MIDI interface for the Swedish tarckerprogram Little Sound DJ for Gameboy.

I figured solving it this way:

1. Taking the MIDI signals trough one of the control ports (passing an interface first).

2. Leaving data (init code, wavetable data or whatever is needed to process sound) on the cartrige.

So, feedback. Is it possible? :/
_________________
"The best optimizer is between your ears..."

#802 - Burre - Fri Jan 10, 2003 7:24 pm

Hmm. 20 views and no replies. Doesn't anyone know?
_________________
"The best optimizer is between your ears..."

#828 - sgeos - Fri Jan 10, 2003 11:30 pm

Burre wrote:
Hmm. 20 views and no replies. Doesn't anyone know?


No clue. Sorry.

-Brendan

#831 - ampz - Sat Jan 11, 2003 12:11 am

C64 SID sounds is like the song of angels. ;-)
NES sounds just gives you a headache...

#840 - Burre - Sat Jan 11, 2003 2:36 am

ampz wrote:
C64 SID sounds is like the song of angels. ;-)
NES sounds just gives you a headache...


I don't agree. SID music is great but can be somewhat noisy sometimes. NES sounds are more "lush" and warm.

Anyway, anyone know of any clever way to store and transfer the ROM data? I'm thinking about builing a connector for the NES and connect some existant memory unit. Perhaps buying an Xport, programming the FPGA I/O layout and connect it to the connector and in to the NES.

For the MIDI interface I'll have to study the format and figure out a way to extract note on/off, insttrument data and perhaps some modulation channel if possible. Since the controller ports recieves asyncronous signals and generate IRQ (I think), it shouldn't be impossible, but I would like confirmation if anyone knows.
_________________
"The best optimizer is between your ears..."

#5976 - Rattus - Wed May 14, 2003 2:44 pm

The MIDI protocol is easy enough, 2-3 async 10bit packets (start and stop on the ends of each) per message; the first packet contains the channel number being addressed and type of MIDI message being sent (there are only 8) and the next 1-2 packets contain the data to use for notes/effects. I just had to write an exam on MIDI, and was idly wondering about doing a GBA MIDI implimentation for my University final year project...