2-4
Functional Description
2.1.1.2 I/O Space
The PCI specification defines I/O space as a contiguous 32-bit I/O
address that is shared by all system resources, including the
LSI53C1000.
Base Address Register Zero (BAR0) (I/O)
determines
which 256-byte I/O area this device occupies.
2.1.1.3 Memory Space
The PCI specification defines memory space as a contiguous 64-bit
memory address that is shared by all system resources.
determines which 1-Kbyte memory
area this device occupies. The SCSI function uses an 8-Kbyte SCRIPTS
RAM memory space.
Base Address Register Two (BAR2) (MEMORY)
determines the 8-Kbyte memory area the SCRIPTS RAM occupies.
2.1.2 PCI Bus Commands and Functions Supported
Bus commands indicate to the target the type of transaction the master
is requesting. Bus commands are encoded on the C_BE[3:0]/ lines
during the address phase. PCI bus commands and encoding types
appear in
.
Table 2.1
PCI Bus Commands and Encoding Types
C_BE[3:0]/ Command Type
Supported
as Master
Supported
as Slave
0000
Interrupt Acknowledge
No
No
0001
Special Cycle
No
No
0010
I/O Read
Yes
Yes
0011
I/O Write
Yes
Yes
0100
Reserved
N/A
N/A
0101
Reserved
N/A
N/A
0110
Memory Read
Yes
Yes
0111
Memory Write
Yes
Yes
1000
Reserved
N/A
N/A
Содержание LSI53C1000
Страница 6: ...vi Preface...
Страница 16: ...xvi Contents...
Страница 28: ...1 12 Introduction...
Страница 234: ...4 124 Registers...
Страница 314: ...6 40 Specifications This page intentionally left blank...
Страница 318: ...6 44 Specifications This page intentionally left blank...
Страница 344: ...6 70 Specifications This page intentionally left blank...
Страница 350: ...6 76 Specifications Figure 6 42 LSI53C1000 329 Ball Grid Array Bottom view...
Страница 352: ...6 78 Specifications...
Страница 360: ...A 8 Register Summary...
Страница 376: ...IX 12 Index...