Sony SMO-F551 Technical Manual page 41

Data bus (7-0,P) (DB)
Eight data-bit signals and a parity-bit signal form the Data Bus. DB(7) is the most
significant bit and the highest priority during the ARBITRATION phase. Bit number,
significance, and priority of Data Bus bit decreases as the bit number decreases.
(DB(0) is the least significant.) A data bit is defined as ONE when the signal value is
true. And it is defined as ZERO when the signal value is false. Data parity DB(P) is
odd.
For the status of the signals relating to control of the drive and details of the timing of
the SCSI bus, refer to the ANSI X3.131-1994 (SCSI-2) documents. Single-ended
drivers have been adopted for the bus drive. Use a device which satisfies the
standards for the driving and receiving circuits.
SMO-F551 Technical Guide and Specifications
Sony Corporation 1998
41