|
发表于 2008-10-21 16:23:13
|
显示全部楼层
In burst mode, embedded controller has received the burst enable command from the host, has halted normal processing, and is waiting for a series of commands to be sent from the host. this allows OSPM or system management handler to quickly read and write several bytes of data at a time without the overhead of SCIs between the commands. / S+ p* O0 Z7 u, N
一般情况下, OSPM与EC通信均是通过SCIs事件方式(interrupt-driven command processing)来完成, 但当在需要传输比较多数据时, 如SMBus Block 的大量数据传输时, OSPM可以发送 Bust Enable Command 请求EC进入burst Mode, 在此模式下, EC将中止正常的其它处理, 只处理与 OSPM 进行的全速的读/写操作, 此时, 不再是以SCIs事件来触发每一次的读写,而是查询方式(polled command processing)进行, 但这样处理不能超过 1ms:
3 Y8 o. t* \- T0 D$ _$ W( c• First Access – 400 microseconds
0 M9 w, E) x# f1 a3 A) j. x• Subsequent Accesses – 50 microseconds each0 ^- j, ?7 \4 z$ k9 V- A
• Total Burst Time – 1 millisecond
2 }) T+ Z5 x: H; A当EC在收到 OSPM 发送的 Bust Disable Command 后, 则结束 Burst mode. |
|