External Hardware Synth As Sound Source

Probably a pretty basic question, but I am new in the world of hardware synths.

Is it possible to use my KAWAI K4 synth as a source of sounds, and to be triggered by MIDI information that “comes” from Renoise? (So I’m not talking about the simple recording of the synth’s analog signal.)

To be more specific: Can my synth operate like a simple software VST, in spite the fact that it is an external hardware unit?

Is it possible to set up MIDI and analog out to work this way?

I have a FireFace UC with 2 MIDI outs and 2 MIDI ins, and the KAWAI has a MIDI in, out and thru + analog outs of course.

EDIT

I’ve just found the section in the Renoise manual that explains this:
http://tutorials.renoise.com/wiki/MIDI

ext. MIDI : The MIDI device is routed to an external synthesizer, which then outputs its own sound directly.

LineIn Ret : The MIDI device is routed to an external synthesizer, but the audio signal is routed back to Renoise via a#Line Input device.

Am I right?

Yep, so use Ext. MIDI mode if your computer & K4 are run into a mixer, or use LineIn ret. mode if you want to get the K4’s signal running through the software mixer in Renoise.

Hey, thanks radian! In the meantime I just realized that it is simplier and - in term of creative process - better simply record my ideas through analog.