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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:$ v7 V- Q( c; T9 t4 X( [* a
The firmware hub relies on the Intel Firmware Hub interface to communicate with the outside world." M/ k. ] _) S
This interface consists of four bi-directional signals and one control input. The timing and electrical4 n: m$ B: }, `4 G8 Q* S! O
parameters of the FWH interface are similar to those of the LPC interface, to provide compatibility
# }! @! D+ Y' N" c" v5 N) Obetween the interfaces, but differ in cases mentioned earlier in this section (clock pin capacitance), as
6 m, K0 y4 }$ M2 }well as in certain timing parameters. The Intel ICH has been engineered to accommodate both interfaces,+ L1 p* s( k: ~0 P- t
which allows the Intel FWH interface signals to be communicated over the same set of pins as LPC. The/ |) d( j4 ~$ O
Intel FWH interface is designed to use an LPC-compatible start cycle, with a reserved cycle type code.
: p/ ^0 {% L# U" J+ i8 x3 C4 ] a ^This ensures that all LPC devices present on the shared interface will ignore cycles destined for the
( O, J/ s O" RFWH, without becoming confused by the different protocol.
6 _5 B; |* Z" r" P3 eFWH和LPC基本是兼容的,不过FWH比LPC多几组命令1 d0 D7 B0 h2 \& t( J
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 A$ |8 W7 @8 i4 }1 g; k另外,可以看看这个:4 Z, Q4 G: }, M8 L8 a4 Z/ n$ ^& G( q
US Patent 7249213 - Memory device operable with a plurality of protocols with configuration data stored in non-volatile storage elements |
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