Terminal Id Register (2D6) - IBM 3278 Technical Reference

Terminal ID Register (2D6)
This 8-bit register is internal to the emulation adapter and is set
and reset by the IBM Personal Computer.
It requires one
address.
This register must be set by the IBM Personal Computer before
enabling the coaxiallin1c
Note: The Terminal ID placed in this register must be the
ones-complement of the data to be sent to the control unit.
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