Omnimaga

General Discussion => Technology and Development => Other => Topic started by: Keoni29 on January 11, 2014, 08:20:17 am

Title: SID synthesizer with MIDI
Post by: Keoni29 on January 11, 2014, 08:20:17 am
I am building a SID synthesizer with a MOS 6581 and an ATmega328 (microcontroller subject to change)



Test setup with MIDI! I want to add some knobs that allow me to change patches and stuff.
The test setup consists of a SID chip, a microcontroller and a 1MHz oscillator circuit.
Title: Re: SID synthesizer with MIDI
Post by: MGOS on January 11, 2014, 08:43:15 am
That sounds awesome! Great job Keoni :)
Title: Re: SID synthesizer with MIDI
Post by: TIfanx1999 on January 11, 2014, 09:31:29 am
Awesome stuff as usual Keoni. ^^
Title: Re: SID synthesizer with MIDI
Post by: Keoni29 on January 31, 2014, 06:17:59 am
Soldered it up and made a little enclosure for it. It has an audio jack, 12Vdc jack, midi jack, DB9 serial rs232, a power and midi LED and a switch for switching between the rs232 and midi port.

IC's used:
MOS6581 SID soundchip
ATmega328 (microcontroller used in the arduino uno)
PC111 optocoupler
TL072 Op-amp
7805 voltage regulator
7812 voltage regulator
MAX232 serial level shifter


(http://8times8.host56.com/wp-content/uploads/2014/01/sid-midi-guts-300x146.jpg)

(http://8times8.host56.com/wp-content/uploads/2014/01/sid-midi-guts2-300x225.jpg)
Title: Re: SID synthesizer with MIDI
Post by: MacBernick on January 31, 2014, 08:59:30 am
Very nice. Is it possible to build one with no electronic knowledge at all ?
Title: Re: SID synthesizer with MIDI
Post by: Keoni29 on January 31, 2014, 09:42:45 am
I am afraid not. Not unless I make a pcb for it so you can just pop in the parts.
Title: Re: SID synthesizer with MIDI
Post by: MacBernick on January 31, 2014, 09:48:05 am
Wiring is OK I guess as long as I know where to put the wires ^^
Title: Re: SID synthesizer with MIDI
Post by: Keoni29 on January 31, 2014, 09:54:20 am
It's pretty complex. I had to do some troubleshooting in order to get it to work. There is about 2m of wire in this at least.
Title: Re: SID synthesizer with MIDI
Post by: MacBernick on January 31, 2014, 09:57:02 am
I see.
Nice job anyway. I love the SID and I'd really like to have a real one with a MIDI controller. Emulations are not really perfect usually.
Title: Re: SID synthesizer with MIDI
Post by: Keoni29 on January 31, 2014, 12:18:59 pm
Yeah that is why I made this too. I made a soundchip for my calculator using the same microcontroller I am using for this project, but the emulation does not sound close enough to the original. It is a nice soundchip emulator for a calculator, but it cannot play back all sid tunes correctly. This thing however can play back anything in theory.
Title: Re: SID synthesizer with MIDI
Post by: MacBernick on January 31, 2014, 12:28:17 pm
Can you control the envelope generators of the chip with your circuit, via MIDI and/or with actual knobs ?
Title: Re: SID synthesizer with MIDI
Post by: Keoni29 on January 31, 2014, 12:31:10 pm
At the moment I have some hardcoded patches that you can choose from, but in the future you will be able to store custom patches in the microcontroller's memory. There are no knobs on the synth and there are no plans for adding them in the future. I pretty much used up all I/O pins on the microcontroller.