實時軟件過程之間的緩沖通信

　　實時軟件過程之間的緩沖通信

　　假設(shè)您有兩個流程：服務(wù)器和客戶機。服務(wù)器進程從硬件接口讀取一些I/O，并將數(shù)據(jù)傳遞給客戶機進程。這些進程可能在不同的處理器上運行，也可能不會運行。特別是，它們沒有共同的共享內(nèi)存區(qū)域。

　　In this situation the server and client have to communicate over some explicit pipe between them. This communication mechanism may be implemented in different ways depending on the system. The server part of this system can be run with code similar to the following pseudo-code：

　　while （1） {

　　get_data_from_pins（）;

　　send_data_to_client（）;

　　}

　　and the client part can run with the following code pattern：

　　while （1） {

　　wait_for_then_get_data_from_server（）;

　　process_data（）;

　　}

　　In this case， the server initializes the communication and the client waits for and responds to the communication. So the server is the master and the client is the slave. This is perhaps to be expected since the whole process is driven by the arrival of data on the hardware interface. So far， this is simple. However， things get a bit more complicated if timing requirements are taken into account. Depending on the needs of the system， the protocol between the two processes may have to be more complicated.