【導(dǎo)讀】RTX51是一個(gè)適用于8051家族的實(shí)時(shí)多任務(wù)操作系統(tǒng)。和軟件設(shè)計(jì)以及有時(shí)間限制的工程開(kāi)發(fā)變得簡(jiǎn)單。RTX51是一個(gè)強(qiáng)大的工具，它。任務(wù)或中斷的消息、信號(hào)量。RTX51Tiny可以很容易的運(yùn)行在。沒(méi)有擴(kuò)展外部存儲(chǔ)器的單片機(jī)系統(tǒng)上。但是，使用RTX51Tiny的程序可以訪問(wèn)。RTX51Tiny允許循環(huán)任務(wù)切換，并且支持信號(hào)傳遞，還能并行的利。RTX51Tiny的os_wait函數(shù)可以等待以下事件：時(shí)間到、時(shí)間間隔、以后的部分用RTX-51來(lái)指代RTX-51Full和RTX-51Tiny。的地方會(huì)加以說(shuō)明。RTX-51是一個(gè)強(qiáng)大的實(shí)時(shí)操作系統(tǒng)，并且易于應(yīng)用。系列的微處理器上。你使用標(biāo)準(zhǔn)C語(yǔ)言編寫(xiě)RTX-51應(yīng)用程序，并且用C51來(lái)編譯。為了具體指明任務(wù)的標(biāo)志和優(yōu)先級(jí)，會(huì)與標(biāo)準(zhǔn)C存在一點(diǎn)差別。用程序要求你將件包含進(jìn)來(lái)。一個(gè)無(wú)窮循環(huán)，也可以被認(rèn)為是一個(gè)連續(xù)執(zhí)行的單個(gè)任務(wù)。好的時(shí)間片內(nèi)得以執(zhí)行。時(shí)間到使正在執(zhí)行的任務(wù)掛起，并使另一個(gè)任務(wù)開(kāi)始執(zhí)。期間，作業(yè)1得以執(zhí)行。發(fā)出信號(hào)，在os_wait函數(shù)控制下的任務(wù)才結(jié)束等待狀態(tài)。送出來(lái)，那么任務(wù)將立即繼續(xù)執(zhí)行。

　　

【正文】 tf and getlinecall these basic I/O routines. The traffic light application will also operatewithout using interrupt driven serial I/O. but will not perform as well. is the mand line editor for characters received from the serial port. This source file is also used by the MEASURE application. TRAFFIC Project 19 Open the project file that islocated in \KEIL\C51\EXAMPLES\TRAFFIC folderwith μVision2. The source files for theTRAFFIC project will be shown in theProject Window – Files page. The RTX51 Tiny RealTime OS is selected under Options for Target. Build the TRAFFIC program with Project Build or the toolbar button. Run the TRAFFIC Program You can test TRAFFIC with theμVision2 simulator. The watch variables shown on the rightallow you to view port status that drivesthe lights. The push_keysignal functionsimulates thepedestrianpush key thatswitches thelight system towalk functionis called withthe Push forUse Debug – Function Editor to open . This file is specified 20 the Push forWalk toolbarbutton. under Options for Target – Debug – Initialization File and defines thesignal function push_key, the port initialization and the toolbar button. Note: the VTREG symbol Clock is literalized with a back quote (`),since there is a C function named clock in the to “Literal Symbols” on page 121 for more information. Now run the TRAFFIC application. Enable View – Periodic WindowUpdate to view the lights in the watch window during program execution. The Serial Window 1 displays the printf output and allows you to enterthe traffic light controller mands described in the table above. Set the clocktime outside ofthe start/endtime intervalto flash theyellow light. RTX Kernel Aware Debugging A RTX application can be tested with the same methods and mands asstandard 8051 applications. When you select an Operating System underOptions for Target – Target, μVision2 enables additional debugging features:a dialog lists the operating system status and with the _TaskRunning_ debugfunction you may stop program execution when a specific task is active. The following section exemplifies RTX debugging with the TRAFFIC example. Stop program execution, reset the CPU and kill all breakpoints. An RTX51 application can be tested in the same way as standardapplications. You may open source files, set break points and single stepthrough the code. The TRAFFIC application starts with task 0 init. μVision2 is pletely kernel aware. You may display the task statuswith the menu mand Peripherals – RTX Tiny Tasklist. 21 The dialog RTX51 Tiny Tasklist gives you the following information: 頭 描述 TID task_id used in the definition of the task function. Task Name name of the task function. State task state of the function。 explained in detail in the next table. Wait for event the task is waiting for。 the following events are possible (also in bination): Event Timeout: the task Timer is set to the duration is specified with the os_wait function call. After the Timer decrements to zero, the task goes into Ready state. Interval: the time interval specified with os_wait is added to the task Timer value. After the Timer decrements to zero, the task goes into Ready state. Signal: the os_wait function was called with K_SIG and the task waits for Sig = 1. Sig status of the Signal bit that is assigned to this task. Timer value of the Timer that is assigned to this task. The Timer value decrements with every RTX system timer tick. If the Timer bees zero and the task is waiting for Timeout or Interval the task goes into Ready state. Stack value of the stack pointer (SP) that is used when this task is Running. RTX51 Tiny contains an efficient stack management that is explained in the RTX51 Tiny User’sGuide, Chapter 5: RTX51 Tiny, Stack Management. This manual provides detailed information about the Stack value. S 狀態(tài) 描述 Deleted Tasks that are not started are in the Deleted state. Ready Tasks that are waiting for execution are in the Ready state. After the currently Running task has finished processing, RTX starts the next task that is in the Ready 22 state. Running The task currently being executed is in the Running state. Only one task is in the Running state at a time. Timeout Tasks that were interrupted by a roundrobin timeout are in the Timeout state. This state is equivalent to Ready。 however, a roundrobin task switch is marked due to internal operating procedures. Waiting Tasks that are waiting for an event are in the Waiting state. If the event occurs which the task is waiting for, this task then enters the Ready state. The Debug – Breakpoints… dialog allows you to define breakpoints that stopthe program execution only when the task specified in the _TaskRunning_debug function argument is Running. Refer to “Predefined Functions” on page134 for a detailed description of the _TaskRunning_ debug function. The breakpoint at the function signalon stops execution only if lights is the current Running task.