Here is the issue:
I have an Arturia Keystep. Using CV and Gate outputs, the synth works as it should.
Under MIDI, there is nothing. I am using CH1, but tried several different channels. The learning apparently worked, but it took several minutes for the LED to start blinking again (timeout?).
Here is what works: MIDI is read by the MCU, because I can read it on the MIDI out. Exactly what key I am hitting, note on, etc is reflected immediately on the output MIDI port. [So MIDI channel is working to MCU]
The voltage on the DAC (IC20, pin 8) does not change. It stays at 0.579V when I push any key
IC20, pin 1= 4.982V, pin 2 = 4.191V, pin 3 = 0.040V, pin 4 = 4.925, pin 5 = 0V, pin 6 = 1.806V, pin 7 = 0V and pin 8 = 0.579
All power checks out, on all points in the troubleshooting sheets
There is continuity from IC23-15 to IC20-2, and from IC23-13 to IC19-2
I double checked resistors, etc… I am at a loss. Both the DAC_Pitch signal and external VCO_CV_IN are supposed to go to IC6 on pin 2 (after a couple resistors). Again continuity is good.
Here is another thing, under auto tuning, there are two tones, a low and a high. The voltage for the high tone (At VCO test point or IC20-8) is at 0.579V and drops to 0.156 V for the low tone. Tells me the DACs are likely working.
The tuning cycle never stops, just plays two tones, each for about 6 seconds. I can change the pitch by turning the Cutoff up or down.
Anything to point to would be appreciated.