BTS supports the 3270 bridge function. (The 3270 bridge is described in the CICS® External Interfaces Guide.) This means that BTS applications can be integrated with, and make use of, existing 3270-based applications.
Even though BTS activities are not terminal-related (they are never started directly from a terminal), a BTS activity can use a 3270-based program.
BTS’s support for the 3270 bridge is described in Reusing existing 3270 applications in BTS.