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June 20, 2015 at 11:10 pm #11510ChibunduParticipant
With reference to the article Digital Clock using PIC Microcontroller and DS1307 RTC. Can anyone help me with the explanation of setting hour in the switch case 1 ?
// LCD module connections sbit LCD_RS at RB2_bit; sbit LCD_EN at RB3_bit; sbit LCD_D4 at RB4_bit; sbit LCD_D5 at RB5_bit; sbit LCD_D6 at RB6_bit; sbit LCD_D7 at RB7_bit; sbit LCD_RS_Direction at TRISB2_bit; sbit LCD_EN_Direction at TRISB3_bit; sbit LCD_D4_Direction at TRISB4_bit; sbit LCD_D5_Direction at TRISB5_bit; sbit LCD_D6_Direction at TRISB6_bit; sbit LCD_D7_Direction at TRISB7_bit; // End LCD module connections unsigned short read_ds1307(unsigned short address) { unsigned short r_data; I2C1_Start(); I2C1_Wr(0xD0); //address 0x68 followed by direction bit (0 for write, 1 for read) 0x68 followed by 0 --> 0xD0 I2C1_Wr(address); I2C1_Repeated_Start(); I2C1_Wr(0xD1); //0x68 followed by 1 --> 0xD1 r_data=I2C1_Rd(0); I2C1_Stop(); return(r_data); } void write_ds1307(unsigned short address,unsigned short w_data) { I2C1_Start(); // issue I2C start signal //address 0x68 followed by direction bit (0 for write, 1 for read) 0x68 followed by 0 --> 0xD0 I2C1_Wr(0xD0); // send byte via I2C (device address + W) I2C1_Wr(address); // send byte (address of DS1307 location) I2C1_Wr(w_data); // send data (data to be written) I2C1_Stop(); // issue I2C stop signal } unsigned char BCD2UpperCh(unsigned char bcd) { return ((bcd >> 4) + '0'); } unsigned char BCD2LowerCh(unsigned char bcd) { return ((bcd & 0x0F) + '0'); } int Binary2BCD(int a) { int t1, t2; t1 = a%10; t1 = t1 & 0x0F; a = a/10; t2 = a%10; t2 = 0x0F & t2; t2 = t2 << 4; t2 = 0xF0 & t2; t1 = t1 | t2; return t1; } int BCD2Binary(int a) { int r,t; t = a & 0x0F; r = t; a = 0xF0 & a; t = a >> 4; t = 0x0F & t; r = t*10 + r; return r; } int second; int minute; int hour; int hr; int day; int dday; int month; int year; int ap; unsigned short set_count = 0; short set; char time[] = "00:00:00 PM"; char date[] = "00-00-00"; void main() { I2C1_Init(100000); //DS1307 I2C is running at 100KHz CMCON = 0x07; // To turn off comparators ADCON1 = 0x06; // To turn off analog to digital converters TRISA = 0x07; PORTA = 0x00; Lcd_Init(); // Initialize LCD Lcd_Cmd(_LCD_CLEAR); // Clear display // Lcd_Cmd(_LCD_CURSOR_OFF); // Cursor off Lcd_Cmd(_LCD_BLINK_CURSOR_ON); Lcd_out(1,1,"Time:"); Lcd_out(2,1,"Date:"); do { set = 0; if(PORTA.F0 == 0) { Delay_ms(100); if(PORTA.F0 == 0) { set_count++; if(set_count >= 7) { set_count = 0; } } } if(set_count) { if(PORTA.F1 == 0) { Delay_ms(100); if(PORTA.F1 == 0) set = 1; } if(PORTA.F2 == 0) { Delay_ms(100); if(PORTA.F2 == 0) set = -1; } if(set_count && set) { switch(set_count) { case 1: hour = BCD2Binary(hour); hour = hour + set; hour = Binary2BCD(hour); if((hour & 0x1F) >= 0x13) { hour = hour & 0b11100001; hour = hour ^ 0x20; } else if((hour & 0x1F) <= 0x00) { hour = hour | 0b00010010; hour = hour ^ 0x20; } write_ds1307(2, hour); //write hour break; case 2: minute = BCD2Binary(minute); minute = minute + set; if(minute >= 60) minute = 0; if(minute < 0) minute = 59; minute = Binary2BCD(minute); write_ds1307(1, minute); //write min break; case 3: if(abs(set)) write_ds1307(0,0x00); //Reset second to 0 sec. and start Oscillator break; case 4: day = BCD2Binary(day); day = day + set; day = Binary2BCD(day); if(day >= 0x32) day = 1; if(day <= 0) day = 0x31; write_ds1307(4, day); // write date 17 break; case 5: month = BCD2Binary(month); month = month + set; month = Binary2BCD(month); if(month > 0x12) month = 1; if(month <= 0) month = 0x12; write_ds1307(5,month); // write month 6 June break; case 6: year = BCD2Binary(year); year = year + set; year = Binary2BCD(year); if(year <= -1) year = 0x99; if(year >= 0x50) year = 0; write_ds1307(6, year); // write year break; } } } second = read_ds1307(0); minute = read_ds1307(1); hour = read_ds1307(2); hr = hour & 0b00011111; ap = hour & 0b00100000; dday = read_ds1307(3); day = read_ds1307(4); month = read_ds1307(5); year = read_ds1307(6); time[0] = BCD2UpperCh(hr); time[1] = BCD2LowerCh(hr); time[3] = BCD2UpperCh(minute); time[4] = BCD2LowerCh(minute); time[6] = BCD2UpperCh(second); time[7] = BCD2LowerCh(second); date[0] = BCD2UpperCh(day); date[1] = BCD2LowerCh(day); date[3] = BCD2UpperCh(month); date[4] = BCD2LowerCh(month); date[6] = BCD2UpperCh(year); date[7] = BCD2LowerCh(year); if(ap) { time[9] = 'P'; time[10] = 'M'; } else { time[9] = 'A'; time[10] = 'M'; } Lcd_out(1, 6, time); Lcd_out(2, 6, date); Delay_ms(100); }while(1); }
June 21, 2015 at 5:10 pm #11519Ligo GeorgeKeymaster -
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