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SMO-F551 Technical Guide and Specifications
Sony Corporation 1998
The following are the descriptions on the signals:
Busy (BSY)
An "OR-tied" signal that indicates whether the bus is being used.
Select (SEL)
A signal used either by the initiator to select the target or by the target to reselect an
initiator.
Control/Data (C/D)
A signal driven by the target to indicate whether CONTROL or DATA information is on
the DATA BUS. True indicates CONTROL.
Input/Output (I/O)
A signal driven by the target to control the direction of data flow on the DATA BUS with
respect to the initiator. True indicates input to the initiator. This signal also
distinguishes phases between SELECTION and RESELECTION.
Message (MSG)
A signal driven by the target during the MESSAGE phase.
Request (REQ)
A signal driven by the target to indicate a request for REQ/ACK data transfer
handshake.
Acknowledge (ACK)
A signal driven by the initiator to indicate an acknowledgment for an REQ/ACK data
transfer handshake.
Attention (ATN)
A signal driven by the initiator to indicate the ATTENTION condition.
Reset (RST)
An "OR-tied" signal that indicates the RESET condition.
