The basic functionality seems to be working, finally! :)
This means, four oscillators (in the SNES DSP) are producing a constant sound while frequency and volume can be changed with the potentiometers connected to the cartridge. The GUI is just a still image at the moment, but it will display some information regarding the four oscillators and also the user will be able to change waveforms and effects from the GUI.
I am working on the second iteration of the PCB at the moment which will feature PCB mount potentiometers and also 3,5mm audio jacks for CV input from other synthesizers. These CV inputs may be used for AMP CV or Pitch CV in the future. Also the potentiometers might be mappable from the GUI. We'll see about that... It all depends on whether someone other than me is interested in these features. :D
When the second iteration PCBs come along, and the housing is done too, I will give some devices away for cost of the parts, which is about 20€. If there are any willing testers out there I might even have some devices for free.