VT100.net VT102 User Guide
Chapter 6 Contents  
Table 6-3 Modem Control Feature Selections
Selection Description Usual Application
FDX A Full-duplex with no EIA modem control (data leads only) Full-duplex communication with a null modem (direct) connection to the computer or with a modem that does not use modem control signals.
FDX B Full-duplex with EIA modem control Full-duplex communication with a modem that uses modem control signals.
FDX C Asymmetric full-duplex with EIA modem control Full-duplex communication with a half-duplex modem using the secondary channel.
HDX A Half-duplex supervisory mode Half-duplex communication with the secondary channel control lines indicating when to perform line turnarounds.
HDX B Half-duplex coded control Half-duplex communication with control characters indicating when to perform line turnarounds.
Chapter 6 Contents  
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