STM32f4 RTC Alarm with LCD

[haythem]

Posted on June 19, 2014 at 17:40

HI, i want to configure the RTC alarm with LCD, to goal is to display the time in a LCD. I set the LCD and RTC but I do not know commant display the time on the LCD

This is my code to configure the RTC alarm

1. void RTC_Config(void)
2. {
3. RTC_TimeTypeDef RTC_TimeStructure;
4. RTC_InitTypeDef RTC_InitStructure;
5.   /* Enable the PWR clock */
6.   RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);
7.   /* Allow access to RTC */
8.   //PWR_BackupAccessCmd(ENABLE);
9.   /* Reset RTC Domain */
10.   RCC_BackupResetCmd(ENABLE);
11.   RCC_BackupResetCmd(DISABLE);
12.   /* Enable the LSE OSC */
13.   RCC_LSEConfig(RCC_LSE_ON);
14.   /* Wait till LSE is ready */  
15.   while(RCC_GetFlagStatus(RCC_FLAG_LSERDY) == RESET)
16.   {
17.   }
18.   /* Select the RTC Clock Source */
19.   RCC_RTCCLKConfig(RCC_RTCCLKSource_LSE);
20.   /* Define the RCC with hours */
21.   RTC_InitStructure.RTC_AsynchPrediv = 0x7F;
22.   RTC_InitStructure.RTC_SynchPrediv  = 0xFF;
23.   RTC_InitStructure.RTC_HourFormat   = RTC_HourFormat_24;
24.   RTC_Init(&RTC_InitStructure);
25.   
26.   /* Define time to 00h 00mn 00s AM */
27.   RTC_TimeStructure.RTC_H12     = RTC_H12_AM;
28.   RTC_TimeStructure.RTC_Hours   = 0x00;  //0 h
29.   RTC_TimeStructure.RTC_Minutes = 0x00;  //0 Minutes
30.   RTC_TimeStructure.RTC_Seconds = 0x00;  // Secands
31.   RTC_SetTime(RTC_Format_BCD, &RTC_TimeStructure);
32.   
33. }
34. void RTC_AlarmConfig(void)
35. {
36.   EXTI_InitTypeDef EXTI_InitStructure;
37.   RTC_AlarmTypeDef RTC_AlarmStructure;
38.   NVIC_InitTypeDef NVIC_InitStructure;
39.   
40.   /* EXTI configuration */
41.   EXTI_ClearITPendingBit(EXTI_Line17);
42.   EXTI_InitStructure.EXTI_Line = EXTI_Line17;
43.   EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
44.   EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
45.   EXTI_InitStructure.EXTI_LineCmd = ENABLE;
46.   EXTI_Init(&EXTI_InitStructure);
47.   
48.   /* Enable the RTC Alarm Interrupt */
49.   NVIC_InitStructure.NVIC_IRQChannel = RTC_Alarm_IRQn;
50.   NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
51.   NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
52.   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
53.   NVIC_Init(&NVIC_InitStructure);
54.  
55.   /* Set the alarmA Masks */
56.   RTC_AlarmStructure.RTC_AlarmMask = RTC_AlarmMask_All;
57.   RTC_SetAlarm(RTC_Format_BCD, RTC_Alarm_A, &RTC_AlarmStructure);
58.   
59.   /* Set AlarmA subseconds and enable SubSec Alarm : generate 8 interripts per Second */
60.   RTC_AlarmSubSecondConfig(RTC_Alarm_A, 0xFF, RTC_AlarmSubSecondMask_SS14_5);
61.   /* Enable AlarmA interrupt */
62.   RTC_ITConfig(RTC_IT_ALRA, ENABLE);
63. }

[Tesla DeLorean]

Posted on June 19, 2014 at 17:52

Perhaps you can use

http://www.cplusplus.com/reference/cstdio/sprintf/

to compose a string in the format you want, and then print the string to the LCD.

[haythem]

Posted on June 19, 2014 at 18:16

Thank you , i have a problem with ''

PWR_BackupAccessCmd(ENABLE);''  than keil give me this erreur ''.\TIM_PWM_Output\TIM_PWM_Output.axf: Error: L6218E: Undefined symbol PWR_BackupAccessCmd (referred from main.o).'' i use the stm32f4  discovery library

[Tesla DeLorean]

Posted on June 19, 2014 at 18:57

Make sure you have the library file stm32f4xx_pwr.c in your project

[haythem]

Posted on June 21, 2014 at 19:21Thank you for your support, now I think that I have successfully configured the RTC Alarm. Here is my setup code, but my problem is that I can not display the seconds, minutes and hours on the LCD. Else can you help me to resolve this problem?

1. void RTC_Config(void)
2. {
3. RTC_TimeTypeDef RTC_TimeStructure;
4. RTC_InitTypeDef RTC_InitStructure;
5.   /* Enable the PWR clock */
6.   RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);
7.   /* Allow access to RTC */
8.   PWR_BackupAccessCmd(ENABLE);
9.   /* Reset RTC Domain */
10.   RCC_BackupResetCmd(ENABLE);
11.   RCC_BackupResetCmd(DISABLE);
12.   /* Enable the LSE OSC */
13.   RCC_LSEConfig(RCC_LSE_ON);
14.   /* Wait till LSE is ready */  
15.  /* while(RCC_GetFlagStatus(RCC_FLAG_LSERDY) == RESET)
16.   {
17.   }*/
18.   /* Select the RTC Clock Source */
19.   RCC_RTCCLKConfig(RCC_RTCCLKSource_LSE);
20.   /* Define the RCC with hours */
21.   RTC_InitStructure.RTC_AsynchPrediv = 0x7F;
22.   RTC_InitStructure.RTC_SynchPrediv  = 0xFF;
23.   RTC_InitStructure.RTC_HourFormat   = RTC_HourFormat_24;
24.   RTC_Init(&RTC_InitStructure);
25.   
26.   /* Define time to 00h 00mn 00s AM */
27.   RTC_TimeStructure.RTC_H12     = RTC_H12_AM;
28.   RTC_TimeStructure.RTC_Hours   = 0x00;  //0 h
29.   RTC_TimeStructure.RTC_Minutes = 0x00;  //0 Minutes
30.   RTC_TimeStructure.RTC_Seconds = 0x00;  // Secands
31.   RTC_SetTime(RTC_Format_BCD, &RTC_TimeStructure);
32.   
33. }
34. void time_config(void)
35. {
36. RTC_AlarmTypeDef RTC_AlarmStructure;
37. RTC_AlarmCmd(RTC_Alarm_A, DISABLE);   /* disable before setting or cann't write */
38. /* set alarm time 8:30:0 everyday */
39. RTC_AlarmStructure.RTC_AlarmTime.RTC_H12     = RTC_H12_AM;
40. RTC_AlarmStructure.RTC_AlarmTime.RTC_Hours   = 0x08;
41. RTC_AlarmStructure.RTC_AlarmTime.RTC_Minutes = 0x30;
42. RTC_AlarmStructure.RTC_AlarmTime.RTC_Seconds = 0x0;
43. RTC_AlarmStructure.RTC_AlarmDateWeekDay = 0x31; // Nonspecific
44. RTC_AlarmStructure.RTC_AlarmDateWeekDaySel = RTC_AlarmDateWeekDaySel_Date;
45. RTC_AlarmStructure.RTC_AlarmMask = RTC_AlarmMask_DateWeekDay; // Everyday 
46. RTC_SetAlarm(RTC_Format_BCD, RTC_Alarm_A, &RTC_AlarmStructure);
47. /* Enable Alarm */
48. RTC_ITConfig(RTC_IT_ALRA, ENABLE);
49. RTC_AlarmCmd(RTC_Alarm_A, ENABLE);
50. RTC_ClearFlag(RTC_FLAG_ALRAF);
51. }
52. void RTC_AlarmConfig(void)
53. {
54.   EXTI_InitTypeDef EXTI_InitStructure;
55.   RTC_AlarmTypeDef RTC_AlarmStructure;
56.   NVIC_InitTypeDef NVIC_InitStructure;
57.   
58.   /* EXTI configuration */
59.   EXTI_ClearITPendingBit(EXTI_Line17);
60.   EXTI_InitStructure.EXTI_Line = EXTI_Line17;
61.   EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
62.   EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
63.   EXTI_InitStructure.EXTI_LineCmd = ENABLE;
64.   EXTI_Init(&EXTI_InitStructure);
65.   
66.   /* Enable the RTC Alarm Interrupt */
67.   NVIC_InitStructure.NVIC_IRQChannel = RTC_Alarm_IRQn;
68.   NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
69.   NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
70.   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
71.   NVIC_Init(&NVIC_InitStructure);
72.  
73.   /* Set the alarmA Masks */
74.   RTC_AlarmStructure.RTC_AlarmMask = RTC_AlarmMask_All;
75.   RTC_SetAlarm(RTC_Format_BCD, RTC_Alarm_A, &RTC_AlarmStructure);
76.   
77.   /* Set AlarmA subseconds and enable SubSec Alarm : generate 8 interripts per Second */
78.   RTC_AlarmSubSecondConfig(RTC_Alarm_A, 0xFF, RTC_AlarmSubSecondMask_SS14_5);
79.   /* Enable AlarmA interrupt */
80.   RTC_ITConfig(RTC_IT_ALRA, ENABLE);
81. }

[Tesla DeLorean]

Posted on June 21, 2014 at 22:37

And what Board and LCD are we talking about? Are there no demos/examples for your board using the LCD? STemWin, etc?

STM32F4xx_DSP_StdPeriph_Lib_V1.0.0\Project\STM32F4xx_StdPeriph_Examples\RTC\RTC_StopWatch\main.c

/* Get the Curent time */
RTC_GetTime(RTC_Format_BCD, &RTC_TimeStruct);
/* Display the curent time and the sub second on the LCD */
RTC_Time_display(Line2, Black , RTC_Get_Time(Secondfraction , &RTC_TimeStruct));

[haythem]

Posted on June 22, 2014 at 00:49

I work with keil ARM bord, i was connected an LCD 16*2 to my stm32f4

[Tesla DeLorean]

Posted on June 22, 2014 at 01:43

Ok, and can you output characters and strings to your display?

And can you use sprintf() to create a string to send to the display from the time structure read from the RTC?

[haythem]

Posted on June 22, 2014 at 03:57

To write in LCD i use this function, but that is no work with RTC

1. void LCD_Print(char* str){ // Print a null terminated string.
2. struct TASK Task;
3. int strPtr;
4. strPtr = 0;
5. //LCD_WaitNotBusy(); // Wait until we are not busy first
6. while(*(str + strPtr) != 0){
7. Task.Command = WriteData;
8. Task.Data = WriteData | *(str + strPtr);
9. Task.Iter = 0;
10. LCD_PushTask(Task);
11. strPtr++;
12. }
13. return;
14. }

[Tesla DeLorean]

Posted on June 22, 2014 at 04:21

Wouldn't something like this suffice?

{
char String[16];
RTC_TimeTypeDef RTC_TimeStruct;
/* Get the Curent time */
RTC_GetTime(RTC_Format_BCD, &RTC_TimeStruct);
sprintf(String,''%02X:%02X:%02X'',
RTC_TimeStruct.RTC_Hours,
RTC_TimeStruct.RTC_Minutes,
RTC_TimeStruct.RTC_Seconds);
LCD_Print(String);
}