MSP430G2553 electronic clock experiment

Use msp430g2553 to control the 1602 LCD to display time, and you can set the time by pressing the button. I made two modes: forward timing and countdown.

/************************************************************************
msp430g2553 and 1602 pin connection
* PIN1 --> Ground
* PIN2 --> VCC (must be connected to +5V)
* PIN3 --> floating during simulation, 2K resistor in actual circuit --> ground (the resistor can be 500-2k, changing the resistor can change the brightness of the character display, and improper connection of the resistor will result in nothing being displayed)
* PIN4 --> RS --> P1.6
* PIN5 --> R/W --> GND
* PIN6 --> EN --> P1.7
* PIN7 --> D0 not connected
* PIN8 --> D1 not connected
* PIN9 --> D2 not connected
* PIN10 --> D3 not connected
* PIN11 --> D4 --> P2.4
* PIN12 --> D5 --> P2.5
* PIN13 --> D6 --> P2.6
* PIN14 --> D7 --> P2.7
* PIN15 --> VCC
* PIN16 --> Ground

* Connection between msp430g2553 and key pins

*k1-->p1.2

*k2-->p1.3

*k3-->p2.1

*k4-->p1.1

Note: I use a matrix keyboard. If you use independent buttons, you need to connect resistors
********************************************************************/

code show as below:

#include
#include
#include
#define LCD_EN_PORT P1OUT //The following 2 should be set to the same port
#define LCD_EN_DDR P1DIR
#define LCD_RS_PORT P1OUT //The following 2 should be set to the same port
#define LCD_RS_DDR P1DIR
#define LCD_DATA_PORT P2OUT //The following 3 should be set to the same port
#define LCD_DATA_DDR P2DIR //Be sure to use the upper 4 bits
#define LCD_RS BIT6
#define LCD_EN BIT7
#define LCD_DATA BIT7|BIT6|BIT5|BIT4 //4-bit data line connection mode
//Function declaration
void LCD_init(void);
void LCD_init_first(void);
void LCD_en_write1(void); //Rising edge enable
void LCD_en_write2(void); //Falling edge enable
void LCD_write_command(unsigned char command);
void LCD_write_data(unsigned char data);
void LCD_set_xy (unsigned char x, unsigned char y);
void LCD_write_string(unsigned char X, unsigned char Y, unsigned char *s);
void LCD_write_char(unsigned char char
add,unsigned char date);
void delay_1ms(void);
void delay_nus(unsigned int n) ;
void delay_nms(unsigned int n);
void SetTime() ; void
SetMode();
void CalledByTimerA();
unsigned char LCDBuf1[]={"Hello world"};//The content to be displayed in the first line
unsigned char LCDBuf2[]={"10:30:00" }; //The content to be displayed in the second line is


unsigned char shi1,fen1,miao1,aa,shi2,fen2,miao2;
unsigned char miao=0;
unsigned char fen=30;
unsigned char shi=10;


unsigned char aa=0;//Counter
int set_flag=0;//Time setting flag
int time_flag=0;//Select


void main()//Main function
{
  WDTCTL = WDTPW + WDTHOLD; // Turn off watchdog
  LCD_init_first();
  LCD_init();
  delay_nms(100);


 BCSCTL3 |= LFXT1S_2; // Set LFXT1 to vol clock, i.e. 12kHZ       
 CCTL0|= CCIE; //Set capture/compare control register, CCIE=0x0010, enable capture compare interrupt 
 CCR0 =182; //Set capture/compare register, initial value is 12000, for ACLK clock frequency of 12khz, equivalent to 1s 
 TA0CTL = TASSEL_1 +TACLR+MC_1;  
 
 P1DIR|=BIT0;//P1.0 is LED, display button works
 P1OUT|=BIT0+BIT3;//P1IN low level jump
 P1REN|=BIT2+BIT3+BIT1;//Pull-up resistor, it seems that it cannot be used without it
 P2REN|=BIT1;




  LCD_write_string(0,0," Mode ");
  delay_nms(10);
  LCD_write_string(0,1,"k1(up) k2(down) ");
  SetMode();
   LCD_write_string(0,0," ");
  delay_nms(10);
  LCD_write_string(0,1," ");
  
  delay_nms(10); 
  LCD_write_string(0,0,LCDBuf1);
  delay_nms(10);
  LCD_write_string(0,1,LCDBuf2);


  _EINT(); //Enable interrupt, this is an internal process supported by the C compiler. 
 set_flag=0;
 while(1)
 { 
   P1OUT&=~BIT0;
    SetTime();
    P1OUT=BIT0+BIT3;
 }
}


/**********************************************************
K1-Enter and set the current time.
K2-Set the hour.
K3-Set the minute.
K4-Confirm and complete the setting.
******************************************************/
void SetTime()
{
  if(!(P1IN&BIT2))
   {
      delay_nms(10);
     // P1OUT&=~BIT0;  
      set_flag=1;
      TA0CTL&=0xffcf; //Stop mode


   }
   else if(!(P1IN&BIT3) && set_flag)
   {
          delay_nms(50);
          shi=(shi+1)%24;
          display_HMS( 0x40,shi);
          LCD_write_command(0x80+0x41);
         // P1OUT&=~BIT0;
   }
   else if (!(P2IN&BIT1) && set_flag)
   {
      delay_nms(50);
      // P1OUT&=~BIT0;
       fen=(fen+1)%60;
       display_HMS(0x43,fen);
       LCD_write_command(0x80+0x44) ;
   }
   else if (!(P1IN&BIT1)&& set_flag)
   {
     delay_nms(10);
      TA0CTL = TASSEL_1 +TACLR+MC_1;
     // P1OUT&=~BIT0;
       set_flag=0;
   }
   else
   {
     // P1OUT=BIT0+BIT3;
   }
 
}
/******************************************************
K1-mode 1, time
K2-mode 2, countdown
K3-confirmation
************************************************/
void SetMode()
{
  while(1)
  {
    if(!(P1IN&BIT2))
    {
      
      time_flag=1;


    }
    else if(!(P1IN&BIT3))
    {
       time_flag=2;
    }
 
   if(time_flag!=0 &&!(P2IN&BIT1))
   {
      break;
   }
  }
  LCD_write_command(0x0c); //Display on, off cursor, no blinking
}


/****************************************************
Display hours, minutes and seconds
****************************************************/
void display_HMS(unsigned char add,unsigned char date)
{
unsigned char shi,ge;
shi=date/10;
ge=date%10;
LCD_write_command(add+0x80);
LCD_write_data(0x30+shi);
LCD_write_data(0x30+ge);
}


/************************************************************
LCD1602 LCD initialization function
****************************************************/
void LCD_init_first(void) //LCD1602 LCD initialization function (hot start)
{
        delay_nms(500);
        LCD_DATA_DDR|=LCD_DATA; //Data port direction is output
        LCD_EN_DDR|=LCD_EN; //Set EN direction to output
        LCD_RS_DDR|=LCD_RS; //Set RS direction to output


        delay_nms(50);
        LCD_write_command(0x30);
        delay_nms(50);
        LCD_write_command(0x30);
        delay_nms(5);
        LCD_write_command(0x30);
        delay_nms(500);


}
void LCD_init(void)
{
delay_nms(500);
LCD_DATA_DDR|=LCD_DATA; //Data port direction is output
LCD_EN_DDR|=LCD_EN; //Set EN direction to output
LCD_RS_DDR|=LCD_RS; //Set RS direction to output


delay_nms(500);


LCD_write_command(0x28); //4-bit data interface
delay_nms(50);
LCD_write_command(0x28); //4-bit data interface
delay_nms(50);
LCD_write_command(0x28); //4-bit data interface
delay_nms(50);
LCD_en_write2();
delay_nms(50);
LCD_write_command(0x28); //4-bit data interface
delay_nms(500);
LCD_write_command(0x01); //Clear screen
LCD_write_command(0x0c); //Display on and off cursor, no blinking
LCD_write_command(0x06); //Set input mode, increment without shifting
delay_nms(50);
}


/********************************************************
 LCD enable rising edge
********************************************************/
void LCD_en_write1(void)
{
    LCD_EN_PORT&=~LCD_EN;
    delay_nus(10);
    LCD_EN_PORT|=LCD_EN;
}
/********************************************************
LCD enable falling edge
****************************************************/
void LCD_en_write2(void)
{
   LCD_EN_PORT|=LCD_EN;
   delay_nus(10);
   LCD_EN_PORT&=~LCD_EN;
}


/********************************************************
Write instruction function
****************************************************/
void LCD_write_command(unsigned char command)
{
   delay_nus(16);
   P2SEL=0x00;
   LCD_RS_PORT&=~LCD_RS; //RS=0
   LCD_en_write1();
   LCD_DATA_PORT&=0X0f; //clear high four bits
   LCD_DATA_PORT|=command&0xf0; //write high four bits


  delay_nus(16);
   LCD_en_write2();
   command=command<<4; //move low four bits to high four bits
   LCD_en_write1();
   LCD_DATA_PORT&=0x0f; //clear high four bits
   LCD_DATA_PORT|=command&0xf0; //write low four bits
   LCD_en_write2();
}




/******************************************************
Write data function
************************************************/
void LCD_write_data(unsigned char data)
{
   delay_nus(16);
   P2SEL=0x00;
   LCD_RS_PORT|=LCD_RS; //RS=1
   LCD_en_write1(); //E rising edge
   LCD_DATA_PORT&=0X0f; //clear high four bits
   LCD_DATA_PORT|=data&0xf0; //write high four bits
   delay_nus(16);
   LCD_en_write2();
   data=data<<4; //Move the lower four bits to the upper four bits
   LCD_en_write1();
   LCD_DATA_PORT&=0X0f; //Clear the high four bits
   LCD_DATA_PORT|=data&0xf0; //Write the lower four bits
   LCD_en_write2();
}


/*******************************************************
Write address function
************************************************/
void LCD_set_xy( unsigned char x, unsigned char y )
{
   unsigned char address;
   if (y == 0) address = 0x80 + x;
   else address = 0xc0 + x;
   LCD_write_command( address);
}


/*****************************************************
LCD writes a string at any position, column x=0~15, row y=0,1
*******************************************************/
void LCD_write_string(unsigned char X,unsigned char Y,unsigned char *s)
{
LCD_set_xy( X, Y ); //write addresswhile
    (*s) //write display character
    {
      LCD_write_data( *s );
      s++;
    }
}


/*******************************************************
LCD writes characters at any position, column x=0~15, row y=0,1
********************************************************/
void LCD_write_char(unsigned char X,unsigned char Y,unsigned char data)
{
   LCD_set_xy( X, Y ); //write addressLCD_write_data
   ( data);
}


/*******************************************************
1us delay function
************************************************/
void delay_1us(void)
{
   asm("nop");
}


/********************************************************
N us delay function
****************************************************/
void delay_nus(unsigned int n)
{
   unsigned int i;
  for (i=0;i   delay_1us();
}


/**************************************************
1ms delay function
***************************************************/
void delay_1ms(void)
{
   unsigned int i;
   for (i=0;i<1140;i++);
}


/******************************************************
N ms delay function
***************************************************/
void delay_nms(unsigned int n)
{
   unsigned int i=0;
   for (i=0;i   delay_1ms();
}


/****************************************************
 Interrupt response function mode 1
************************************************/
void CalledByTimerA()
{  
   if(aa>=60)//One second is up
   { 
     aa=0;//clear 0
     miao++; 
   }
   if(miao>=60)//one point
   { 
     miao=0; 
     fen++; 
   }
   if(fen>=60)
   { 
     fen=0;
     shi++;
     LCD_write_command(0x80+0x45);//Display "：" between minutes and seconds
     LCD_write_data(':');
   }
   if(shi>=24)
   {
    shi=0;
    display_HMS(0x43,shi); 
    LCD_write_command(0x80+0x42);//Display "：" between hours and minutes
    LCD_write_data(':'); 
   }


   display_HMS(0x46,miao);
   display_HMS(0x43,fen);
   display_HMS(0x40,shi);


  LCD_write_command(0x87);
  LCD_write_command(0x84);


}
/****************************************************
 Interrupt response function mode 2
************************************************/
void CalledByTimerAForCountDown()
{ 


  if(aa>=60)
  {
      aa=0;
      if(miao<=0)
      {
        if(fen<=0)
       {
           if(shi<=0)
           {
          
           }
           else
           {
              shi--;
              fen=59;
              miao=59;
            }
       }
       else
       {
        fen--;
        miao=59;
        }
      }
         else
        {
           miao--;
        }
        
    
    LCD_write_command(0x80+0x45);//Display "：" between minutes and seconds
    LCD_write_data(':');
 
    LCD_write_command(0x80+0x42);//Display "：" between hours and minutes
    LCD_write_data(':'); 




   display_HMS(0x46,miao);
   display_HMS(0x43,fen);
   display_HMS(0x40,shi);


    LCD_write_command(0x87);
    LCD_write_command(0x84);
    
   }
 
}
/******************************************************
Timer interrupt
************************************************/
#pragma vector=TIMER0_A0_VECTOR
__interrupt void Timer_A(void)
{
 aa++;
 if(time_flag==1)
 {
  CalledByTimerA();
 }
 else if(time_flag==2)
 {
   CalledByTimerAForCountDown();
 }
 
}