[solved] DigiFX problem

Hi all

When built 1 or 2 weeks ago, my digiFX board was working fine…since yesterday, no way I can get the green light flashing…

Tried with 2 differents digital control boards, several way of connection between TX and RX, flashed the 328p again…I checked continuity between Tx and RX, it’s fine…I’m a bit lost now…

Damn, it has worked…what could be the problem ?

cheers !

Tom.

The digital board not set to “dsp”?

checked 5 times…yes, set to dsp…by the way, the filter section (cutoff, resonance) doesn’t have any effect on the sound…

It clearly looks like a communication problem between the two boards, on the TX line. Can you scope the TX>RX connection?

Crotte

No scope at home (or elsewhere)…If I can get my hand on a scope, what is the procedure:

  • scope between GND and TX>RX ?
  • should see a square wave, which shape depends on the effect applied ?

You should see a square wave, with “bursts” of data transmission every ms. The waveform should change as you modify cutoff/resonance or the VCA gain.

Really weird…it’s sometimes working if I tweak the CV choice (changing between 4CV in, prgm, pedals)…It’s as if I had to initialize the FX board…

edit: but not reproductible

Oh, and is it normal that tweaking the CV choice randomly affects the 4 parameters of the first filter page (cutoff reso env lfo)?

Seems to be more a problem with your Digital board ? A Similar behavior you can see at the programmer if something is bridged together…

weird because it happens with both Digital boards, which used to work perfectly fine with SMR filter boards AND digifx…

> Oh, and is it normal that tweaking the CV choice randomly affects the 4 parameters of the first filter page (cutoff reso env lfo)?

Yes it does. When you set the CV to pedals or pgm, the values read from the CV inputs are written to the patch rather than to the modulation matrix. And since you don’t have anything connected to the CV inputs…

That’s what I thought. Well one weirdy point solved…but the main point is not !

To check if the connection pins were involved in the problem, I directly soldered a small wire from TX to RX…still the same problem…

What else than TX>RX could be involved ?

You mention the green LED not lighting up ; but the red LED correctly lights up in sync with the note on/off messages?

In fact, I’m working with an external audio signal…red LED does light up in sync with the snare drum I send…

Does it make a difference working with external audio or shruthi-generated sounds ?

even if you work with an external audio signal, you need to trigger a note on the Shruthi to open the VCA

Ok, shame on me…

I think I’ll get some stinging nettle to flagellate myself.

Thanks a lot…

Back to music now !

Cheers,

Tom.

PS: shame on me, shame on me, shame on me, etc.

Maybe some advice regarding the VCA should be silkscreened near the Audio In Jack…

Maybe we just have to be warned that the VCA can only be opened via note on…or maybe it’s already in the documentation and I just missed it…

From the Manual… " 5: Line-level, mono audio input. Note that the external audio signal flows through the VCF and the VCA – you won’t hear anything until a note or sequence is played by the Shruthi-1 to “open” the VCA. "

My precedent “Shame on me” does really make sense…stupid I am !