Well it’s been awhile since I’ve done this (with midi cc device) and it seems I’ve forgotten how, so a… noob question
did a search btw but didn’t see anything addressing my exact question.
I hit ctrl + m, select a slider, move the knob I’d like to automate in the vst but it doesn’t want to attach to the midi control device. tried it with several vst’s including some I’ve done this with in the past and it isn’t working.
VSTs do not (usually) broadcast MIDI back to the host in this way. You can confirm this by looking at Renoise’s MIDI activity lights in the top/right corner of the screen, and seeing that they do not blink when you move knobs/sliders in a VST plugin. The method you’re trying here will of course work if you have an external MIDI controller hooked up and you move a knob/slider there.
To automate VST synth parameters using the Automation Device, you must make sure the Automation Device is first linked to the correct instance of the VST synth, and then you must select the parameter manually from the available list in Renoise. Unfortunately some synths have very obscure internal parameter names, so some trial and error may be needed here.
To automate VST synth parameters using the MIDI-Control Device, again, make sure the correct instance of the synth is linked, and then you must set a CC number to use in the control device itself. This must correspond to whatever MIDI CC the synth’s parameter is set to. You would probably find a MIDI CC mapping list in the plugin’s manual/readme, or it may be possible via the plugin’s interface to choose your own CC numbers. Alternatively, if the plugin itself has a MIDI learn mode, then enable that for the specific parameter you want, and then (I think) you should be able to move the slider in Renoise to automatically connect it to whichever CC number you have chosen.