Avago Technologies LSI8751D - Manual (Page 98)

4-6 Signal Descriptions
The PCI/SCSI pin definitions are organized into the following functional
groups: System, Address/Data, Interface Control, Arbitration, Error
Reporting, SCSI, and Optional Interface. A slash (/) at the end of the
signal name indicates that the active state occurs when the signal is at
a LOW voltage. When the slash is absent, the signal is active at a HIGH
voltage.
There are four signal type definitions:
I Input, a standard input-only signal.
O Output, a standard output driver (typically a Totem Pole Output).
T/S 3-state, a bidirectional, 3-state input/output signal.
S/T/S Sustained 3-state, an active LOW 3-state signal owned and driven by
one and only one agent at a time.