4. uCOS配置

uCOS是可裁减实时操作系统，可以根据实际的应用对内核未使用到的功能进行裁减，以进一步节省系统宝贵的硬件资源，通常可用的uCOS-II内核代码在6K~26K，这在uCOS-II配置文件os_cfg.h中进行配置，这个配置文件在源码目录为os_cfg_r.h，从目录中拷贝添加到uCOS/uCOS-II/Cfg目录中，并重命名为os_cfg.h。

  1. #ifndef OS_CFG_H
  2. #define OS_CFG_H
  3. /* ---------------------------- MISCELLANEOUS -------------------------- */
  4. #define OS_CFG_APP_HOOKS_EN   1u   /* Enable/Disable application specific hooks*/
  5. #define OS_CFG_ARG_CHK_EN        1u   /*Enable/Disable argument checking*/
  6. #define OS_CFG_CALLED_FROM_ISR_CHK_EN   1u   /* check for called from ISR*/
  7. #define OS_CFG_DBG_EN                  1u   /* Enable (1) debugcode/variables */
  8. #define OS_CFG_ISR_POST_DEFERRED_EN    0u   /* Enable/Disable DeferredISR posts */
  9. #define OS_CFG_OBJ_TYPE_CHK_EN                 1u   /* Enable/Disable object typechecking*/
  10. #define OS_CFG_TS_EN                    1u   /* Enable/Disable timestamping*/
  11. #define OS_CFG_PEND_MULTI_EN            1u   /* code generation formulti-pend feature */
  12. #define OS_CFG_PRIO_MAX                32u   /* maximum number of taskpriorities */
  13. #define OS_CFG_SCHED_LOCK_TIME_MEAS_EN 1u   /* code to measure schedulerlock time */
  14. #define OS_CFG_SCHED_ROUND_ROBIN_EN      1u   /* code for Round-Robinscheduling */
  15. #define OS_CFG_STK_SIZE_MIN              64u   /* Minimum allowable taskstack size */
  17. /* ----------------------------- EVENT FLAGS --------------------------- */
  18. #define OS_CFG_FLAG_EN                  1u   /* Enable/Disable code forEVENT FLAGS*/
  19. #define OS_CFG_FLAG_DEL_EN              0u   /* Include code forOSFlagDel()*/
  20. #define OS_CFG_FLAG_MODE_CLR_EN      0u   /* code for Wait on ClearEVENT FLAGS*/
  21. #define OS_CFG_FLAG_PEND_ABORT_EN   0u   /* Include code forOSFlagPendAbort()*/
  24. /* -------------------------- MEMORY MANAGEMENT ------------------------ */
  25. #define OS_CFG_MEM_EN                  1u   /* code generation for MEMORYMANAGER */
  27. /* --------------------- MUTUAL EXCLUSION SEMAPHORES ------------------- */
  28. #define OS_CFG_MUTEX_EN                 1u   /* code generation for MUTEX*/
  29. #define OS_CFG_MUTEX_DEL_EN             0u   /* code for OSMutexDel()*/
  30. #define OS_CFG_MUTEX_PEND_ABORT_EN     0u   /* code for OSMutexPendAbort()*/
  32. /* --------------------------- MESSAGE QUEUES -------------------------- */
  33. #define OS_CFG_Q_EN                      1u   /* code generation for QUEUES*/
  34. #define OS_CFG_Q_DEL_EN                    0u   /* Include code forOSQDel()*/
  35. #define OS_CFG_Q_FLUSH_EN                 0u   /* Include code forOSQFlush()*/
  36. #define OS_CFG_Q_PEND_ABORT_EN         1u   /* Include code forOSQPendAbort()*/
  38. /* ----------------------------- SEMAPHORES ---------------------------- */
  39. #define OS_CFG_SEM_EN                          1u  /* code generation for SEMAPHORES */
  40. #define OS_CFG_SEM_DEL_EN                    0u   /* Include code forOSSemDel()*/
  41. #define OS_CFG_SEM_PEND_ABORT_EN       1u   /* Include code forOSSemPendAbort()*/
  42. #define OS_CFG_SEM_SET_EN                     1u   /* Include code forOSSemSet()*/
  44. /* -------------------------- TASK MANAGEMENT -------------------------- */
  45. #define OS_CFG_STAT_TASK_EN             1u   /* Enable/Disable thestatistics task*/
  46. #define OS_CFG_STAT_TASK_STK_CHK_EN    1u   /* Check task stacks fromstatistic task*/
  47. #define OS_CFG_TASK_CHANGE_PRIO_EN      1u   /* Include code forOSTaskChangePrio()*/
  48. #define OS_CFG_TASK_DEL_EN              0u   /* Include code forOSTaskDel()*/
  49. #define OS_CFG_TASK_Q_EN                  1u   /* Include code forOSTaskQXXXX()*/
  50. #define OS_CFG_TASK_Q_PEND_ABORT_EN    0u   /* Include code forOSTaskQPendAbort()*/
  51. #define OS_CFG_TASK_PROFILE_EN          1u   /* variables in OS_TCB forprofiling */
  52. #define OS_CFG_TASK_REG_TBL_SIZE        1u   /* Number of task specificregisters*/
  53. #define OS_CFG_TASK_SEM_PEND_ABORT_EN  1u   /* Include code forOSTaskSemPendAbort()*/
  54. #define OS_CFG_TASK_SUSPEND_EN          1u   /* OSTaskSuspend() and OSTaskResume()*/
  56. /* -------------------------- TIME MANAGEMENT -------------------------- */
  57. #define OS_CFG_TIME_DLY_HMSM_EN           1u   /* Include code forOSTimeDlyHMSM()*/
  58. #define OS_CFG_TIME_DLY_RESUME_EN      0u   /* Include code forOSTimeDlyResume()*/
  60. /* ------------------- TASK LOCAL STORAGE MANAGEMENT ------------------- */
  61. #define OS_CFG_TLS_TBL_SIZE    0u   /* code for Task LocalStorage (TLS) registers */
  63. /* ------------------------- TIMER MANAGEMENT -------------------------- */
  64. #define  OS_CFG_TMR_EN            1u   /*Enable/Disablecode generation for TIMERS */
  65. #define OS_CFG_TMR_DEL_EN   0u   /*Enable/Disable code generation for OSTmrDel()*/
  67. #endif

5. 用户代码

用户需要提供一个周期性定时中断作为uCOS-II的运行Tick，每个Tick需调用OSTimeTick()来让内核管理时钟节拍，在s3c2416用定时器4产生这个系统Tick。在main()函数中需调用OSInit()初始化内核，创建任务后，再调用OSStart()把cpu管理权交给内核。内核即可正确地管理用户的任务。

  1. #include "s3c2416.h"
  2. #include "Exception.h"
  3. #include "ucos_ii.h"
  5. // IO port for controling LEDs
  6. #define LED2    (13) // GPE13 LED2
  7. #define LED3    (11) // GPE11 LED3
  8. #define LED4    (13) // GPL13 LED4
  9. #define LED5    (12) // GPE12 LED5
  10. #define LED6    (2)  // GPG2  LED6
  12. OS_STK TaskStartStk[TASK_START_STK_SIZE];
  13. OS_STK  Task1Stk[TASK1_STK_SIZE];
  14. OS_STK  Task2Stk[TASK2_STK_SIZE];
  15. OS_STK  Task3Stk[TASK3_STK_SIZE];
  17. static void Timer4_IRQ(void)
  18. {
  19.     OSTimeTick(); // uCOS时钟节拍管理
  20.     rSRCPND1 |= (0x01 <<INT_TIMER4);       // write 1 to clear
  21.     rINTPND1 |= (0x01 <<INT_TIMER4);       // write 1 to clear
  22. }
  24. void Timer4_Start()
  25. {
  26.     rTCON |= (0x1 << 20); // 定时器开启
  27. }
  29. void Timer4_Stop()
  30. {
  31.     rTCON &= ~(0x1 << 20);// 定时器停止
  32. }
  34. void Timer4_Init()
  35. {
  36. // 定时器4时钟频率为PCLK(66.66666M)/(0+1)/16=4.166MHZ
  37.     rTCFG1 &= ~(0xf << 16);
  38.     rTCFG1 |= (0x3 << 16);  // Timer4 16分频
  39.     rTCFG0 &= ~(0xff << 8);
  40.     rTCFG0 |= (0 << 8); // PCLK预分频为1
  41.     rTCNTB4 = 4166; // System Tick设1ms
  42.     rTCON |= (0x1 << 21); // 更新计数值
  43.     rTCON &= ~(0x1 << 21);// 清除
  44.     rTCON |= (0x1 << 22); // 自动重装载
  46.     IRQ_Register(INT_TIMER4,Timer4_IRQ); // 注册Timer4中断函数
  47.     rINTMOD1 &= ~(1 <<INT_TIMER4); // Timer4 IRQ 模式
  48.     rINTMSK1 &= ~(1 <<INT_TIMER4); // Timer4开中断
  49. }
  51. void Gpio_LED2(unsigned char On)
  52. {
  53.     if (!On) {
  54.         rGPEDAT &=~(1<<LED2);
  55.     } else {
  56.         rGPEDAT |= (1<<LED2);
  57.     }
  58. }
  60. void Gpio_LED3(unsigned char On)
  61. {
  62.     if (!On) {
  63.         rGPEDAT &=~(1<<LED3);
  64.     } else {
  65.         rGPEDAT |= (1<<LED3);
  66.     }
  67. }
  69. void Gpio_LED4(unsigned char On)
  70. {
  71.     if (!On) {
  72.         rGPLDAT &=~(1<<LED4);
  73.     } else {
  74.         rGPLDAT |= (1<<LED4);
  75.     }
  76. }
  78. void Gpio_LED5(unsigned char On)
  79. {
  80.     if (!On) {
  81.         rGPEDAT &=~(1<<LED5);
  82.     } else {
  83.         rGPEDAT |= (1<<LED5);
  84.     }
  85. }
  87. void Gpio_Init()
  88. {
  89.     // GPE11,12,13 LED3,LED5,LED2output   
  90.     rGPECON &=~((0x03<<(LED3<<1)) | (0x03<<(LED5<<1))
  91.                 |(0x03<<(LED2<<1)));
  92.     rGPECON |= ((0x01<<(LED3<<1))| (0x01<<(LED5<<1))
  93.                 |(0x01<<(LED2<<1)));
  94.     // GPL13 LED4 output   
  95.     rGPLCON &= ~(0x03 <<(LED4<<1));
  96.     rGPLCON |= (0x01 <<(LED4<<1));
  97. }
  99. void Task3(void *pdata)
  100. {
  101.     (void)pdata;
  102.     while (1) {
  103.         Gpio_LED5(1);
  104.         OSTimeDly(2000); // LED5 2000ms闪烁
  105.         Gpio_LED5(0);
  106.         OSTimeDly(2000); // LED52000ms闪烁    
  107.     }
  108. }
  110. void  Task2(void *pdata)
  111. {
  112.     (void)pdata;
  113.     while (1) {
  114.         Gpio_LED4(1);
  115.         OSTimeDly(1500); // LED41500ms闪烁
  116.         Gpio_LED4(0);
  117.         OSTimeDly(1500); // LED41500ms闪烁    
  118.     }
  119. }
  121. void  Task1(void *pdata)
  122. {
  123.     (void)pdata;
  124.     while (1) {
  125.         Gpio_LED3(1);
  126.         OSTimeDly(1000); // LED31000ms闪烁
  127.         Gpio_LED3(0);
  128.         OSTimeDly(1000); // LED31000ms闪烁    
  129.     }
  130. }
  132. void  TaskStart(void *pdata)
  133. {
  134.     (void)pdata;
  135.     Gpio_Init();
  136.     Timer4_Init();
  137.     Timer4_Start();
  139.     OSTaskCreate(Task1, (void *)0,&Task1Stk[TASK1_STK_SIZE - 1], Task1Prio);
  140.     OSTaskCreate(Task2, (void *)0,&Task2Stk[TASK2_STK_SIZE - 1], Task2Prio);
  141.     OSTaskCreate(Task3, (void *)0,&Task3Stk[TASK3_STK_SIZE - 1], Task3Prio);
  143.     while (1) {
  144.         Gpio_LED2(1);
  145.         OSTimeDly(500); // LED2 500ms闪烁
  146.         Gpio_LED2(0);
  147.         OSTimeDly(500); // LED2 500ms闪烁
  148.     }
  149. }
  151. int  main (void)
  152. {  
  153.     OSInit(); // 初始化uCOS
  154.     OSTaskCreate(TaskStart, (void *)0,&TaskStartStk[TASK_START_STK_SIZE-1], TaskStartPrio);
  155.    OSStart();// 开始uCOS调度
  156.     return 0;
  157. }

uCOS-II通过app_cfg.h文件来配置任务的栈、优先级等，app_cfg.h的内容如下:

  1. #ifndef APP_CFG_MODULE_PRESENT
  2. #define APP_CFG_MODULE_PRESENT
  4. // 任务TaskStart的栈及优先级分配
  5. #define  TASK_START_STK_SIZE      256u
  6. #define  TaskStartPrio      10
  7. // 任务Task1的栈及优先级分配
  8. #define  TASK1_STK_SIZE         256u
  9. #define  Task1Prio          11
  10. // 任务Task2的栈及优先级分配
  11. #define  TASK2_STK_SIZE         256u
  12. #define  Task2Prio          12
  13. // 任务Task3的栈及优先级分配
  14. #define  TASK3_STK_SIZE         256u
  15. #define  Task3Prio          13
  16. // 定时器优先级配置
  17. #define OS_TASK_TMR_PRIO       (OS_LOWEST_PRIO - 2)
  19. #endif

uCOS-II+uCGUI效果图： 15_GCC下uCOS的移植(2) - 图1 15_GCC下uCOS的移植(2) - 图2

6. 附录

本篇uCOS接口部分的移植对于ARM7、ARM9都是适用的，不同型号的cpu只需加入定时器产生系统Tick，通过调用OSTimeTick()来让内核管理时钟节拍。总的来说，熟悉一款操作系统的工作原理，了解其任务调度、信号量同步、临界区访问等概念，对学习其它操作系统、多线程编程等均是有很较大的帮助的。 uCOS_GCC，GCC下uCOS-II的移植工程，可直接make http://pan.baidu.com/s/1o6NTaVw uCOS_MDK，MDK下uCOS-II的移植工程 http://pan.baidu.com/s/1jGjzE0A