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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:. \9 y" I) d7 r' e: [, j
The firmware hub relies on the Intel Firmware Hub interface to communicate with the outside world.
! W( K6 e) A0 {# [This interface consists of four bi-directional signals and one control input. The timing and electrical2 d5 Q7 T# [! h+ i) d: M
parameters of the FWH interface are similar to those of the LPC interface, to provide compatibility |% g/ i* H, Y4 c: h9 G5 M' p
between the interfaces, but differ in cases mentioned earlier in this section (clock pin capacitance), as& Z9 w" b- @- _" r% o" n0 @6 i6 B
well as in certain timing parameters. The Intel ICH has been engineered to accommodate both interfaces,0 ~8 b4 D, g4 W( F8 ~
which allows the Intel FWH interface signals to be communicated over the same set of pins as LPC. The
' |0 f' m+ h# WIntel FWH interface is designed to use an LPC-compatible start cycle, with a reserved cycle type code. v- B! |( j: p$ H4 h+ c* B- s- k, x
This ensures that all LPC devices present on the shared interface will ignore cycles destined for the9 z# B" u6 Z* R4 ?- z* B9 {
FWH, without becoming confused by the different protocol.' j( |( S& X" `8 r
FWH和LPC基本是兼容的,不过FWH比LPC多几组命令
+ E; t6 i# g( 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.& Z4 N* k. ]2 `
另外,可以看看这个:2 N# y' l# M9 b. e
US Patent 7249213 - Memory device operable with a plurality of protocols with configuration data stored in non-volatile storage elements |
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