I use a Nektar Impact LX61 MIDI keyboard with FL Studio 20. I have a pedal plugged into the 1/4" foot switch jack on the back. Currently, this functions as a "sustain" in that it continues to act as if keys are pressed down after they have been released. However, many piano libraries feature a more realistic sustain function when MIDI CC64 is greater than 50%. The Nektar Impact series does not feature a MIDI CC input for pedals.
When I press down or release the sustain pedal, FL Studio indicates that it is reviving a MIDI signal by lighting up an orange indicator in the top left. I do not, however, know what type of signal this is or what channel it is on. If I knew, I may be able to link it to MIDI CC64 as an on/off (0% or 100%) switch using FL Studio's internal "Remote Control Settings" feature.
I am looking for information regarding how MIDI controllers send data from the foot switch jack. Or even better, if anybody has done this in FL Studio before, I would like to know the process.