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本帖最后由 yuzengshu 于 2009-11-5 13:19 编辑
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1 J1 W8 x6 b% GCPCI 分为系统板，背板，外围板，对于外围板有死规范，但是对于，系统板，和背板的规范* f9 ?/ p T( F5 ?- v9 W4 e% S+ V
，见的不多，就是对于系统板，时钟线和数据线的长度有没有限定，还有背板，时钟和数据长度的限定怎么* X" R7 r& X, D. A# @5 }
计算，希望做过的朋友，给点经验，我的是PCI TO PCI桥出来，在到CPCI接口的，谢谢
6 Y/ b$ c2 P8 i5 j大家看看这段怎么理解6 [& X6 ]; B" r( a7 f
1 The System Slot clock distribution circuitry shall be designed to accommodate
9 i' D( g9 E e* l- U# _$ Nup to 200 ps of backplane and peripheral board skew. The following design rules9 t. ]- C5 D) K$ a% k8 k
apply to clock distribution to backplane peripherals and local (onboard) PCI) {) o9 ]' K m( E
peripherals
5 j" S9 C1 X8 K* K+ z3 `1 x2 Any onboard PCI peripherals connected to the CompactPCI bus, including, H& r9 e- G% j4 T2 c5 M
PCI to PCI bridges, shall be provided a clock that is delayed to& N4 e0 d( X! M' q& M; O% G
accommodate the maximum propagation delay of the backplane clocks and
5 Z8 M5 z* S; g5 G' A3 [still meet the 1 ns overall skew requirement. Up to 800 ps of skew is" Z! D2 u/ p5 h. [3 T' x
allowed for onboard clock distribution (including the clock buffer internal
8 U( `! j2 Z8 @( D! f1 gskew). The onboard clock signals shall be delayed beyond the clocks routed
: O- ]% G; [' K9 J9 G6 n. `8 @to the backplane (Section 3.5.5.1) to accommodate best and worst case7 u% z4 |) X: S1 x/ w
backplane delays and the 63.5mm wire delay on the peripheral board. |
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发表于 2009-11-5 13:17
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淘帖
支持！
反对！