Response Modes

Both normal disconnect mode (NDM) and normal response mode (NRM) are supported.

NDM is entered by default whenever a session is initiated, and is switched to NRM only after completion of the set normal response mode/unnumbered acknowledge (SNRM/UA) command sequence. Once operating in NRM, information frames containing user data can be transferred. NRM then remains active until termination of the SDLC session, which occurs due to the disconnect/unnumbered acknowledge (DISC/UA) command sequence or a major link error. Once termination is complete, SDLC activity halts, and the NDM/NRM modes are not re-entered until another session is initiated.