pd2ly is pure data to lilypond or pitch-duration to lilypond. It is in a very early and experimental version although it is currently working consistently.
For it to work, you must give it:
1. A valid full path (no relative paths I think) and filename, for example the message “open /yourfullpath/myscore.ly”
2. A reference duration, which will be the smallest duration you need in your piece (i.e. a 32nd would have the message “refdur = 32”)
3. A meter (i.e. 4/4 would have the message “meter 4 4”)
I have not been able to use two in the same patch, but I generally use a generative patch to make .txt files and then use pd2ly to convert them into lilypond files. Btw, negative pitch numbers create silences.