LSI53C040-160QFP LSI, LSI53C040-160QFP Datasheet - Page 83

• Manufacturer Part Number: LSI53C040-160QFP
• Manufacturer: LSI

Specifications of LSI53C040-160QFP

• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Supplier Unconfirmed

Register: 0xFC04
Current SCSI Bus Status (CSBS)
Read Only
The Current SCSI Bus Status register is a read only register that
monitors seven SCSI bus control signals plus the data bus parity bit. For
example, an initiator device can use this register to determine the current
bus phase and to poll REQ/ for pending data transfers. The SCSI bus
status information in this register may also help determine why a
particular interrupt occurred.
RST
BSY
REQ
MSG
C_D
I_O
RST
7
x
BSY
6
x
Table 4.2
Bus Phase
Data Out
Undefined
Command
Message Out
Data In
Undefined
Status
Message In
SCSI Reset
Busy
Request
Message
Command/Data
Input/Output
REQ
5
x
SCSI Phase Bit Values
MSG
4
x
Assert MSG/ Assert CD/
0
1
0
1
0
1
0
1
C_D
3
x
I_O
2
x
0
0
1
1
0
0
1
1
SEL
1
x
Assert IO/
0
0
0
0
1
1
1
1
DBP
0
x
4-9
7
6
5
4
3
2