tron v.
[NRL, CMU; prob. fr. the movie "Tron"] To become inaccessible
except via email or talk(1), especially when one is
normally available via telephone or in person. Frequently used in
the past tense, as in: "Ran seems to have tronned on us this
week" or "Gee, Ran, glad you were able to un-tron yourself". One
may also speak of `tron mode'; compare spod.
Note that many dialects of BASIC have a TRON/TROFF command
pair that enables/disables line number tracing; this has no
obvious relationship to the slang usage.