Hi Alex,
It is a super simple external. I tried for a while to simply use the [midiout] object but I couldn't figure out how to get it to actually output anything. I looked at the pd source code, it looks like there is a little bit of code to send clock out messages but I don't think it is exposed to the user in any object... and I didn't see anything about start/stop/continue messages.
A couple of months ago, I was trying to get raw MIDI out of [midiout] myself. (for Sysex messages in my case)
With some advise from the list, I've learned that for reasons I still don't quite understand, [midiout] was not functioning for a while, then was fixed in relatively recent versions of Pd.
I'd be interested in knowing if you will have better results of recent versions of Pd. Perhaps you can turn your external into an abstraction.
-- David Shimamoto