Mini Motari 2600

[Netsurfer_x1]

Hi all.

 

But a question that's been burning in my mind in the past few months is if it is possible to build a synthesizer utilizing the 2600's TIA (or even two of them) to build a Minimoog style synthesizer. I've seen broadly similar projects (google them) like midi controlled TIAs, & the Gatari 2600. But would going all out & adding "Moog style" controls, a VCA, VCF, pitch bend & modulation wheels even work? (assuming it's even possible)

 

Just a question I thought I'd pose to the hardware hackers & mods here. I'm sure this will make for some interesting reading!

[Van]

Well, It's possible. Lots of work! look at Midibox.org for similar projects, SID synth, ect.

Saw a thread @ Electromusic.org for a Pokey synth module, full on CV control.

Gets hard mixing Analog control with Digital chip, but can be done.

[Netsurfer_x1]

I kinda figured it would be. But that's one thing I'm having trouble hashing out: How to have the knobs, switches & whatnot "command" the TIA to produce a certain waveform/sound.

[Van]

There-in lies the problem. Trying to control a digital chip with analog controls.

For a 'rack' style synth module you would have to include some sort of uController to read the analog panel controls or CV inputs. and convert those readings to a digital form to load into the TIA over it's data bus.

You could approach this problem with an arduino or a PIC, choosing a model with a good built in ADC to read the control voltages. But in the end, you will still be faced with quantizing errors, compared to a full analog module, but this may not be of concern compared to the limitations of the TIA.

If you haven't already, take a long look at the SID design @ Midibox.org. It would serve as a good reference for what you are interested in doing. One point you can take away for it is: it doesn't use analog pots, but rather, it uses encoders that function as 'endless' pots. Far easier for the uController to deal with. It may seen very complicated, but the truth is, there just isn't an easy way to do it.

The other approach is to add a midi interface to the A2600 to use it as a hardrsynth. Using a midi sequencer or control surface to 'play' it. LittleScale has released his A26F interface that does this. His blog has the code and instructions to build it.

Have fun, Yogi