Pcie 协议理解

1. OBFF Mechanism  = Optimized Buffer Flush/Fill (OBFF) Mechanism 

cite from: 《PCI EXPRESS BASE SPECIFICATION, REV. 3.1a 》

The Optimized Buffer Flush/Fill (OBFF) Mechanism enables a Root Complex to report to 
Endpoints (throughout a hierarchy) time windows when the incremental platform power cost for 
Endpoint bus mastering and/or interrupt activity is relatively low. 

 

“OBFF” – System memory path available for Device memory read/write bus master activities 

 

2. PRSNT 信号如何连线？

PRSNT1_N

PRSNT2_N_X1

PRSNT2_N_X4

PRSNT2_N_X8

PRSNT2_N_X16     需要学习《PCI_Express_CEM_r3.0_008152013_TS_Clean.pdf》

 

2. SlimSAS的这个信号作用，BP_TYPEB；

解决：

 

基于《SFF-8448_R1.3b.pdf》，

Vendor Specific Pins (VSP) 

3.PCIE的3V3_VAUX电流大小：

 

 

来自：《PCI Express ®   Base Specification Revision 3.1a December 7, 2015 》

PCI Express ®   Card Electromechanical Specification Revision 3.0