- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄67681 > IBM21P100BGB PCI BUS CONTROLLER, PBGA304 PDF資料下載
參數(shù)資料
| 型號(hào)： | 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(yè)數(shù)： | 139/140頁(yè) |
| 文件大小： | 2032K |
| 代理商： | IBM21P100BGB |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)第41頁(yè)第42頁(yè)第43頁(yè)第44頁(yè)第45頁(yè)第46頁(yè)第47頁(yè)第48頁(yè)第49頁(yè)第50頁(yè)第51頁(yè)第52頁(yè)第53頁(yè)第54頁(yè)第55頁(yè)第56頁(yè)第57頁(yè)第58頁(yè)第59頁(yè)第60頁(yè)第61頁(yè)第62頁(yè)第63頁(yè)第64頁(yè)第65頁(yè)第66頁(yè)第67頁(yè)第68頁(yè)第69頁(yè)第70頁(yè)第71頁(yè)第72頁(yè)第73頁(yè)第74頁(yè)第75頁(yè)第76頁(yè)第77頁(yè)第78頁(yè)第79頁(yè)第80頁(yè)第81頁(yè)第82頁(yè)第83頁(yè)第84頁(yè)第85頁(yè)第86頁(yè)第87頁(yè)第88頁(yè)第89頁(yè)第90頁(yè)第91頁(yè)第92頁(yè)第93頁(yè)第94頁(yè)第95頁(yè)第96頁(yè)第97頁(yè)第98頁(yè)第99頁(yè)第100頁(yè)第101頁(yè)第102頁(yè)第103頁(yè)第104頁(yè)第105頁(yè)第106頁(yè)第107頁(yè)第108頁(yè)第109頁(yè)第110頁(yè)第111頁(yè)第112頁(yè)第113頁(yè)第114頁(yè)第115頁(yè)第116頁(yè)第117頁(yè)第118頁(yè)第119頁(yè)第120頁(yè)第121頁(yè)第122頁(yè)第123頁(yè)第124頁(yè)第125頁(yè)第126頁(yè)第127頁(yè)第128頁(yè)第129頁(yè)第130頁(yè)第131頁(yè)第132頁(yè)第133頁(yè)第134頁(yè)第135頁(yè)第136頁(yè)第137頁(yè)第138頁(yè)當(dāng)前第139頁(yè)第140頁(yè)
IBM21P100BGB
IBM 133 PCI-X Bridge R1.1
Clocking and Reset
Page 90 of 131
ppb11_clock_reset.fm.03
July 9, 2001
case for fixed frequency applications with simple clock generators or oscillators. A third possibility may be to
use a “power good” indicator, again if the proper stability assurances can be made. Other ways to provide the
S_CLK_STABLE input signal may also be possible.
The S_CLK_STABLE input provides a further measure of control for cases where the secondary bus mode
and clock frequency could vary from reset to reset, as might occur in motherboard applications with pluggable
slots. Here, the clock generator will need to adapt to the changes along with the bridge. By holding the
S_CLK_STABLE signal initially low during reset, the bridge will not be controlling the S_PCIXCAP network
and the clock generation circuitry is free to do its own mode and frequency determination sequence. The
clock frequency may also be adjusted based on the number of populated slots, determined by the PRSNT
pins of the bus. Then, once the frequency of the S_CLK input is stable, the clock circuit can assert the
S_CLK_STABLE signal to allow the bridge to complete the reset sequence. In any event, though, the clock
generation circuitry must guarantee that the clock frequency it provides falls within the range that the bridge
will ultimately determine and broadcast on the initialization pattern. To do this, the clock generator may need
to be capable of driving proper values on the S_SEL100 and S_PCIXCAP inputs, in addition to controlling the
S_CLK_STABLE signal. A mismatch between the broadcast initialization pattern and the actual operating
mode and frequency of the bus is a violation of the architecture and will cause unpredictable results.
6.5 Driver Impedance Selection
On the IBM 133 PCI-X Bridge R1.1, the output drivers for the bussed PCI / PCI-X interface signals are
capable of two different output impedances: a 40 ohm output impedance for point-to-point applications, and a
20 ohm output impedance for multi-point configurations. The output impedance for the primary and
secondary interfaces is separately controlled, and the bridge selects a default impedance value at the
de-assertion of the bus reset on the basis of the bus mode and frequency initialization pattern which was
received (on the primary interface) or generated (on the secondary interface). The bridge makes the assump-
tion that if a bus is configured to be in PCI-X 133 mode, it will be lightly loaded and therefore have a higher
impedance. Hence, the drivers are put into point-to-point mode for this case. For all other PCI-X and all PCI
configurations, the bridge assumes that the bus is more heavily loaded and has a lower impedance, so the
drivers are set to multi-point mode.
There may be some applications, however, for which these assumptions are inaccurate. For example, one
might want to connect to a conventional PCI device in a point-to-point manner. For exception cases like this,
two control input signals are provided, P_DRVR_MODE for the primary interface and S_DRVR_MODE for
the secondary interface. When these inputs are pulled high, the bridge will change the output impedance of
the drivers on their respective interfaces to the opposite state than was assumed by default, as shown in
Table 10: Driver Impedance Selection
Primary Bus Mode
Default Driver Mode
(P_DRVR_MODE=0)
Driver Mode if
P_DRVR_MODE=1
Secondary Bus
Mode
Default Driver Mode
(S_DRVR_MODE=0)
Driver Mode if
S_DRVR_MODE=1
Conventional PCI
Multi-point (20
W)
Point-to-point (40
W)
Conventional PCI
Multi-point (20
W)
Point-to-point (40
W)
PCI-X 66
Multi-point (20
W)
Point-to-point (40
W)
PCI-X 66
Multi-point (20
W)
Point-to-point (40
W)
PCI-X 100
Multi-point (20
W)
Point-to-point (40
W)
PCI-X 100
Multi-point (20
W)
Point-to-point (40
W)
PCI-X 133
Point-to-point (40
W)
Multi-point (20
W)
PCI-X 133
Point-to-point (40
W)
Multi-point (20
W)
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: |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。