Motorola MVME712-12 用户手册
Support Information
3-12
MVME712-12/-13/A/AM/B Transition Modules and LCP2 Adapter Board UserÕs Manual
3
33
DB07*
DATA bus (bit 7) - most signiÞcant bit and the
highest priority during the arbitration phase.
highest priority during the arbitration phase.
34
DBP*
DATA bus (parity) - data parity is odd. Use of
parity is a system option. Parity is not valid
during the arbitration phase.
parity is a system option. Parity is not valid
during the arbitration phase.
35-37
GND
GROUND
38
TERMPWR
TERMINATOR POWER
39,40
GND
GROUND
41
ATN*
ATTENTION - signal driven by the initiator.
Indicates the attention condition.
Indicates the attention condition.
42
GND
GROUND
43
BSY*
BUS BUSY - OR-tied signal that indicates that
the bus is being used.
the bus is being used.
44
ACK*
ACKNOWLEDGE - signal driven by an initiator
to indicate an acknowledgment for a REQ/ACK
data transfer handshake.
to indicate an acknowledgment for a REQ/ACK
data transfer handshake.
45
RST*
RESET - OR-tied signal that indicates the RESET
condition.
condition.
46
MSG*
MESSAGE - signal driven by the target during
the message phase.
the message phase.
47
SEL*
SELECT - signal used by an initiator to select a
target or by a target to reselect an initiator.
target or by a target to reselect an initiator.
48
D/C*
DATA/COMMAND - signal driven by the
target. It indicates whether command or data
information is on the data bus. True (low)
indicates command.
target. It indicates whether command or data
information is on the data bus. True (low)
indicates command.
49
REQ*
REQUEST - signal driven by a target to indicate
a request for a REQ/ACK data transfer
handshake.
a request for a REQ/ACK data transfer
handshake.
50
O/I*
OUTPUT/INPUT - signal driven by a target that
controls the direction of data movement on the
bus. True (low) indicates input to the initiator.
False (high) indicates output from the initiator.
This signal is also used to distinguish between
selection and reselection phases.
controls the direction of data movement on the
bus. True (low) indicates input to the initiator.
False (high) indicates output from the initiator.
This signal is also used to distinguish between
selection and reselection phases.
Table 3-7. SCSI INTERFACE Interconnect Signals (MVME712B) (Continued)
Pin
Number
Signal
Mnemonic
Signal Name and Description