More midi woes. lulz

hopefully pretty small this time :). midi and out are working perfectly when each cable is plugged in separately. when i have them both plugged in, the midi out contstantly spits out the last read value until i unplug the midi into the shruthi. any ideas? lcd is on so checking solder joints might be an issue. i’m going ot have a poke around now…

digi board 0.5
6n137 with 10k pullup
ground plane sanded down and soldered to to for added strength for the midi connectors…

What do you mean by “the midi out contstantly spits out the last read value”? It acts like a MIDI thru? Then it’s normal behaviour.

i’m probably not describing the problem properly, it’s definitely not normal. the columns in renoise are from left to right: note, vol, pan, delay CC#

midi out connected: when i arm a track in renoise and set it running, each tweak is recorded discretely as the track plays.

midi in and out connected: the last tweak is recorded endlessly and it refires the last note leading to meltdown.

Looks like you have a midi loop, as the notes coming from the Shruthi-1’s Out are routed back via ReNoise.

yeah, it has to be a shruthi problem though, cos it works fine on my bass station synth…

Have you tried seeting the Midi mode to “off” ?

However, I think there’s a mode missing: like “full”, except no midi thru.

when set to off, i can’t record any midi ccs.

Yes, I understood that.
That’s why I meant the Shruthi need another mode at which the MIDI out only send out the knob CC data, sequencer data etc., but no incoming data, i.e. everything but MIDI thru.

It looks like a MIDI loop. Let me see if I can add the mode describe by stuartm.

thanks so much guys. i really appreciate your thoughts. so if this is a firmware thang, we don’t other peeps experience the same feedback loop?

There’s no MIDI mode for what you want to do… You don’t want thru/full because they can cause a loop. You want the Shruthi to send back only “novel” information.

So I have added a new “controller” midi out mode in which only user-initiated knob changes are sent to MIDI out. Everything else is discarded.

I’m not sure I can do efficient feedback loop detection given the meager code size I have now to battle with. But I made some progress yesterday and cleared about 200 bytes.

I guess no one else tried yet to have it fully hooked up to Renoise (I’m using it with Live - without any issues so far).
This also plays a certain part, as Renoise obviously forwarding just as the Shruthi does, hence the loop.
Maybe you can change the MIDI routing/thru there as well.

wow. thanks olivier! i guess i’ll go ahead and box it up so. i think this must also have been the problem on the shruti last time. if i’d have known that i could have saved myself a lot of hassle!

i’m not familiar with much else other than renoise so i’m not sure how other daws handle midi. so basically, most other synths have this feature, and other daws also filter for the same thing?

Most synths have separated in/out/thru ports, and what they receive in “in” never gets thrown back to “out” so no risk of causing a loop.

I don’t have any synth here with only in/out, so I don’t know what their “out” does exactly (CC for edited knobs or thru), and if they detect loops.

I think that some MIDI interface or OS-level MIDI drivers (MIDI Yoke) have loop detection.

ah yes. i understand now. midiyoke does have this. it disables the port if it detects a feedback loop.