基于LPC54114开发板的RTC电子时钟

jinglixixi

在LPC54114的芯片内部配有RTC计时器，使用它与OLED显示屏相配合，可以快速地构成一个RTC电子时钟，其效果如图所示。

file:///C:/Users/PC/AppData/Local/Temp/msohtmlclip1/01/clip_image002.jpg

RTC计时效果

OLED屏的显示驱动，在前面已经介绍过，可直接加以引用。

电子时钟的主程序如下：

1. int main(void)
   
2. {
   
3. int loop = 1;     /* Used to fix the unreachable statement warning */
   
4. uint32_t rtcCount;
   
5. /* Starting time for this example used to set the RTC */
   
6. struct tm startTime = {
   
7. 0,                       /* tm_sec, seconds after the minute, 0 to 59 */
   
8. 15,                     /* tm_min, minutes after the hour, 0 to 59 */
   
9. 1,                       /* tm_hour, hours since midnight, 0 to 23 */
   
10. 5,                       /* tm_mday, day of the month, 1 to 31 */
    
11. 1,                       /* tm_mon, months since January, 0 to 11 */
    
12. (2021 - TM_YEAR_BASE),       /* tm_year, years since base year (1900) */
    
13. /* The following 3 fields are not used by the ConvertTimeRtc() function,
    
14. while the ConvertRtcTime() fucntion will generate data in them from an
    
15. RTC tick (except tm_isdst) */
    
16. 0,                       /* tm_wday, days since Sunday, 0 to 6 */
    
17. 0,                       /* tm_yday, days since January 1, 0 to 365 */
    
18. 0                        /* tm_isdst, Daylight Savings Time flag */
    
19. };
    
20. /* Setup SystemCoreClock and any needed board code */
    
21. SystemCoreClockUpdate();
    
22. Board_Init();
    
23. Board_LED_Set(0, false);
    
24. /* Turn on the RTC 32K Oscillator */
    
25. Chip_RTC_PowerUp(LPC_RTC);
    
26. /* Enable the RTC oscillator, oscillator rate can be determined by
    
27. calling Chip_Clock_GetRTCOscRate()     */
    
28. Chip_Clock_EnableRTCOsc();
    
29. /* Initialize RTC driver (enables RTC clocking) */
    
30. Chip_RTC_Init(LPC_RTC);
    
31. /* RTC reset */
    
32. Chip_RTC_Reset(LPC_RTC);
    
33. /* Start RTC at a count of 0 when RTC is disabled. If the RTC is enabled, you
    
34. need to disable it before setting the initial RTC count. */
    
35. Chip_RTC_Disable(LPC_RTC);
    
36. /* COnvert tm structure to RTC tick count */
    
37. ConvertTimeRtc(&startTime, &rtcCount);
    
38. Chip_RTC_SetCount(LPC_RTC, rtcCount);
    
39. rtcCount += 1;
    
40. Chip_RTC_SetAlarm(LPC_RTC, rtcCount);
    
41. /* Enable RTC */
    
42. Chip_RTC_Enable(LPC_RTC);
    
43. /* Clear latched RTC interrupt statuses */
    
44. Chip_RTC_ClearStatus(LPC_RTC, (RTC_CTRL_ALARM1HZ | RTC_CTRL_WAKE1KHZ));
    
45. /* Enable RTC interrupt */
    
46. NVIC_EnableIRQ(RTC_IRQn);
    
47. /* Enable RTC alarm interrupt */
    
48. Chip_RTC_EnableWakeup(LPC_RTC, (RTC_CTRL_ALARMDPD_EN | RTC_CTRL_WAKEDPD_EN));
    
49. OLED_IO_Init();
    
50. delay_us(10);
    
51. OLED_Init();
    
52. OLED_Clear();
    
53. OLED_ShowString(0,0,"LPC54114 TEST",16);
    
54. OLED_ShowString(0,2,"OLED & RTC",16);
    
55. delay_ms(1000);
    
56. OLED_Clear();
    
57. OLED_ShowString(16,0,"  -  -",16);
    
58. OLED_ShowString(16,2,"  :  :",16);
    
59. /* Sleep and do all the work in the RTC interrupt handler */
    
60. while (loop) {
    
61. if (rtcAlarm) {
    
62. rtcCount = Chip_RTC_GetCount(LPC_RTC) + 1;
    
63. Chip_RTC_SetAlarm(LPC_RTC, rtcCount);
    
64. rtcAlarm = false;
    
65. }
    
66. /* Show RTC time in UT format */
    
67. showTime(Chip_RTC_GetCount(LPC_RTC));
    
68. /* Sleep while waiting for alarm */
    
69. __WFI();
    
70. }
    
71. return 0;
    
72. }

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相应的RTC显示函数为：

1. static void showTime(uint32_t rtcCount)
   
2. {
   
3. struct tm currTime;
   
4. ConvertRtcTime(rtcCount, &currTime);
   
5. /* Todays date */
   
6. OLED_ShowNum(16,0,(currTime.tm_year + TM_YEAR_BASE),2,16);
   
7. OLED_ShowNum(40,0,currTime.tm_mon + 1,2,16);
   
8. OLED_ShowNum(64,0,currTime.tm_mday,2,16);
   
9. /* Current time */
   
10. OLED_ShowNum(16,2,currTime.tm_hour,2,16);
    
11. OLED_ShowNum(40,2,currTime.tm_min,2,16);
    
12. OLED_ShowNum(64,2,currTime.tm_sec,2,16);
    
13. }

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NXP管管

有没有想法出一期视频教程

jinglixixi

NXP管管 发表于 2021-2-5 11:16
有没有想法出一期视频教程

实现个功能啥的还能行，出视频还真发憷呀！先把LPC54114搞定，为DIY挑战赛做好准备。

NXP管管

jinglixixi 发表于 2021-2-5 16:24
实现个功能啥的还能行，出视频还真发憷呀！先把LPC54114搞定，为DIY挑战赛做好准备。 ...

可以可以