symbios logic J21971S-0398, Руководство по установке

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Host Interface
SCSI Interface
66 MetaStor Command Module Installation Guide Revision A, March 1998
Table 13 SCA-2 Signal Descriptions
3#
+12 V +12 V power Power supply voltage for the drives.
+12 V charge +12 V pre-charge A +12 V pre-charge for “hot plugging” the drives.
+5 V +5 V power Power supply voltage for the drives.
+5 V charge +5 V pre-charge A +5 V pre-charge for “hot plugging” the drives.
Mated 1/2 In place lines
Signals used to determine when the drive is in place. Mated 2 is ground for the
drive and can be used as the “drive in place” signal. Mated 1 connects to Mated
2 on the mid-plane.
SYNC + SYNC Spindle
Not used by this command module. A signal used to synchronize spindles
between multiple drives.
RMT_START Remote Start
A signal that specifies whether or not the drive must wait for a command from
the host controller before performing SCSI spin-up. A low signal means wait for
the spin-up command
DLYD_START Delayed Start
When the RM_START signal is high, this signal specifies whether or not the
drive must delay spin-up based on its SCSI ID. If this signal is high, the drive
will spin-up as soon as power is applied. If this signal is low, the drive will delay
spin-up after power is applied for nn seconds (12 seconds x drive SCSI = nn
seconds). If the RM-START signal is low, the DLYD_START signal has no effect
on the drive spin-up
SCSI_ID0-3 SCSI ID Signals used to specify the drive SCSI ID.
ACTIVE_LED Active LED driver
A signal used to activate a remote Active LED that specifies when the drive is
active.
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/DATA
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.