參數(shù)資料
型號: IBM21P100BGB
元件分類: 總線控制器
英文描述: PCI BUS CONTROLLER, PBGA304
封裝: 31 X 31 MM, HEAT SINK, PLASTIC, BGA-304
文件頁數(shù): 59/140頁
文件大?。?/td> 2032K
代理商: IBM21P100BGB
IBM21P100BGB
IBM 133 PCI-X Bridge R1.1
ppb11_operations.fm.03
July 9, 2001
Bus Operation
Page 17 of 131
3.3.1 Memory Read Transactions
Conventional PCI memory read, memory read line, memory read multiple, PCI-X memory read DWord, and
PCI-X memory read block transactions are used to transfer memory data from the originating side of the
bridge to the destination side of the bridge. All memory read transactions are either delayed or split on the
originating interface depending on the mode of the originating interface.
3.3.1.1 PCI to PCI-X Transactions
The IBM 133 PCI-X Bridge R1.1 must translate the conventional memory read command to either the
memory read DWord or the memory read block PCI-X Command. If the conventional memory read command
targets non-prefetchable memory space, the command is translated into a memory read DWord. In any other
instance the conventional memory read command gets translated into memory read block PCI-X command.
The prefetching algorithm for the conventional memory read command in prefetchable space is controlled by
bits 9:8 of the Primary and Secondary Data Buffering Control registers. The default value of these bits indi-
cates that one cache line will be prefetched.
The bridge must translate the conventional Memory Read Line command to the Memory Read Block PCI-X
command. The prefetching algorithm is controlled by bits 7:6 of the Primary and Secondary Data Buffering
Control registers. The default value of these bits indicates that one cache line will be prefetched.
The bridge must translate the conventional memory read multiple command to the memory read block PCI-X
command. The prefetching algorithm is controlled by bits 5:4 of the Primary and Secondary Data Buffering
Control registers. The default value of these bits indicates that a full prefetch will be done, subject to the limit
imposed by the maximum memory read byte count value set by bits (14:12) of the same register. The default
value for this field is 512 bytes or an entire read buffer. Using a value greater than this is possible, but it may
be constrained by the setting of the Split Transaction Commitment Limit value in the Upstream or Down-
stream Split Transaction register, since the target bus is in PCI-X mode. Data fetching operations will be
disconnected at all 1MB boundaries.
3.3.1.2 PCI-X to PCI Transactions
The IBM 133 PCI-X Bridge R1.1 translates PCI-X memory read DWord commands into conventional memory
read commands.
Table 4: Read Transaction Handling
Type of Transaction
Type of Handling
Memory Read
Delayed
Memory Read Line
Delayed
Memory Read Multiple
Delayed
Memory Read DWord (PCI-X)
Split (PCI-X)
Memory Read Block (PCI-X)
Split (PCI-X)
I/O Read
Delayed/Split (PCI-X)
Type 0 Configuration Read
Immediate
Type 1 Configuration Read
Delayed/Split (PCI-X)
相關(guān)PDF資料
PDF描述
IBM21P100BGC PCI BUS CONTROLLER, PBGA304
IBM25403GCX-3JC76C2 RISC PROCESSOR, PQFP16
IBM25405GP-3BA200C2 RISC PROCESSOR, PBGA456
IBM25EMPPC603EFG-100 32-BIT, 100 MHz, RISC PROCESSOR, PQFP240
IBM25EMPPC603EBG-100 32-BIT, 100 MHz, RISC PROCESSOR, CBGA255
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
IBM24L5086 制造商:AVED MEMORY PRODUCTS 功能描述: 制造商:AVED Memory Products 功能描述:
IBM25403GCX-3BC80C2 制造商:IBM 功能描述:RISC PROCESSOR, 160 Pin Plastic BGA
IBM25403GCX-3JC50C2 制造商:IBM 功能描述:403GCX-3JC50C2
IBM25403GCX-3JC66C2 制造商:IBM 功能描述:
IBM25403GCX3JC76C2 制造商:IBM 功能描述: