Is it possible? How would I go about doing this?
you have to use effect commands afaik.
right click on the box with the tick to automate it on or off.
I’d love to be able to use automation for this
With only the options ON and OFF, what would be the benefit?
BTW… effect column is always XFFF and XF00
(X being effect number in the DSP chain, so third effect 3FFF = ON, 3F00 = OFF)
Many of DSPs have SEND or DRY/WET. These parameters can be automated in order to turn the DSP on/off. Yet the perfect way is to use pattern commands.
and BTW, a simple XF01 would turn the DSP on, no need for XFFF!
Some people obviously need it, so they would benefit from it immediately. What if you have filled all 4 effect command columns but you suddenly need to turn something else on/off at that exact moment? Doing it via pattern commands you are stuck with 4 max events at once, but doing it via automation you have no restrictions.
There is no drawback to adding this functionality, as far as I can tell, so why not.
.
The benefit is the ability to set up gated effects more quickly (in a very similar manner to dblue’s glitch 
)
The big problem with gating effects in Renoise boils down to this: We only have 4 effect columns to work with per track. Even if we had more, gating effects with a chain of more than 5 would get very messy, and it’s not really that effective to be managing all that data in the effect columns. That’s not what they’re for.
Adding the ability to gate effects with automation, and perhaps even LFO (think of the possibilities! yay!) would make life a crapload easier for those of us who like to gate our effects.
i believe to turn things on it’s actually XF01, not XFFF.
EDIT: i just tried XFFF, this works too. i guess any numeric values above XF00 will turn the effect on…learn something new everyday…
Lets say you have a chain of three effects, each you want to toggle on and off in succession every row.
ex: ringmod, filter, flanger
01 ringmod on / (prev off)
02 ringmod off / filter on
03 filter off / flanger on
04 flanger off / ringmod on
05 ringmod off / filter on
06 filter off / flanger on
etc…
couldnt this be done with two effect columns?
one to handle the on’s, one to handle the offs?
I am successfully implementing what I proposed above right now.
pattern effects toggling renoise and other effects off and on, xbox controller manipulating other effect parms,
and… I just noticed the effect numbers update automatically in the pattern data if you rearrange/insert more effects 
… if only renoise could cut/paste all pattern effects linked to a DSP, together with that DSP
or am I missing something… ?
I know it DELETES pattern effects when removing a dsp
copying when moving seems moderately logical as an option.
(it also updates the pattern effects’ numbers if you rearrange dsps on a track)