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发表于 2008-8-21 14:36:05
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在Intel® 82802AB/82802AC Firmware Hub (FWH)的data sheet里面,有下面一段话:
0 ?7 X3 p1 a; Z: F/ yThe firmware hub relies on the Intel Firmware Hub interface to communicate with the outside world.
5 s2 Q" ^& R3 C& \This interface consists of four bi-directional signals and one control input. The timing and electrical
; M9 |9 x# U( T! [parameters of the FWH interface are similar to those of the LPC interface, to provide compatibility
. C. e/ j9 p' ?between the interfaces, but differ in cases mentioned earlier in this section (clock pin capacitance), as# U* _2 _3 d8 Y$ |
well as in certain timing parameters. The Intel ICH has been engineered to accommodate both interfaces,
2 Q- G! t7 `0 B# O: V" kwhich allows the Intel FWH interface signals to be communicated over the same set of pins as LPC. The
9 u% c+ L* w9 m+ I7 xIntel FWH interface is designed to use an LPC-compatible start cycle, with a reserved cycle type code.
4 C1 r. [0 y+ s5 H$ @; s0 O# _This ensures that all LPC devices present on the shared interface will ignore cycles destined for the( x) i7 R3 z* e: t; E
FWH, without becoming confused by the different protocol.9 X$ g' Y$ a/ l
FWH和LPC基本是兼容的,不过FWH比LPC多几组命令
) L; P, t7 k( _# N在ICH9上面LPC和FWH的数据地址控制信号线都是相同pin复用的,所以应该是二选一的吧.1 C: S+ J# l8 } [
另外,可以看看这个:
, h& o0 F, d! U- fUS Patent 7249213 - Memory device operable with a plurality of protocols with configuration data stored in non-volatile storage elements |
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