symbios logic J21971S-0398, Руководство по установке

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Host Interface
SCSI Interface
64 MetaStor Command Module Installation Guide Revision A, March 1998
Table 11 Host SCSI Signal Descriptions
3#
BSY BUSY An “or-tied” signal indicating that the bus is being used.
SEL SELECT
A signal used by an Initiator to select a Target or by a Target to re-select an
Initiator.
C/D
COMMAND/DAT
A
A signal driven by a Target indicating whether CONTROL or DATA information
is on the data bus. True indicates CONTROL.
I/O INPUT/OUTPUT
A signal driven by a Target controlling the direction of data movement on the
data bus with respect to the Initiator. True indicates input to the Initiator.
MSG MESSAGE A signal driven by the Target during a MESSAGE phase.
REQ REQUEST
A signal driven by the Target to indicate a request for an REQ/ACK data transfer
handshake.
ACK ACKNOWLEDGE
A signal driven by the Initiator to indicate acknowledgment for an REQ/ACK
data transfer handshake.
ATN ATTENTION A signal driven by the Initiator indicating an ATTENTION condition.
RST RESET An “or-tied” signal indicating the RESET condition.
DB(0-15,P,P1) DATA BUS, PARITY
Sixteen-bit data bus with odd parity used for data transfer and BUS DEVICE ID
during ARBITRATION