//****************************************************************************************** // PIC18F14K50 Sample Program // Project : // Program Name : // Programer : // Create date : Version 1.0 H22.5.05 // History : // Laungage : MPLAB C18 //****************************************************************************************** // (1)Description // //****************************************************************************************** #include #include #include #include #include #include #include #include // //Define configration // #pragma config CPUDIV=NOCLKDIV //CPU System Clock Selection bit(No CPU System Clock divide) #pragma config USBDIV = OFF //USB Clock Selection bit(USB Clock comes directly from the OSC1/OSC2 oscillator block; no divide) #pragma config FOSC = HS //Oscillator Selection bits(HS oscillator) #pragma config PLLEN = ON //X PLL Enable bit(Oscillator multiplied by 4) #pragma config PCLKEN = OFF //Primary Clock Enable Bit(Primary clock is under software control) #pragma config FCMEN = OFF #pragma config IESO = OFF //Internal/External Oscillator Switchover bit(Oscillator Switchover mode disabled) #pragma config PWRTEN = OFF,BOREN = OFF,BORV = 19 #pragma config WDTEN = OFF,WDTPS = 1 #pragma config MCLRE = OFF //MCLR Pin Enable bit(RE3 input pin enabled; MCLR disabled) #pragma config HFOFST = OFF,STVREN = OFF,LVP = OFF,BBSIZ = OFF,XINST = OFF #pragma config CP0 = OFF,CP1 = OFF,CPB = OFF,CPD = OFF,WRT0 = OFF,WRT1 = OFF,WRTB = OFF,WRTC = OFF,WRTD = OFF,EBTR0 = OFF,EBTR1 = OFF,EBTRB = OFF // //Define function // void Wait_1ms(unsigned int); void Timer(void); void main(void) { unsigned int lp; // ***************************** // 1.Initialized Segment // ***************************** // (1)Define I/O port TRISA = 0xFF; TRISB = 0xFF; TRISC = 0x00; PORTC = 0x00; // (2)Define ANSEL ANSEL = 0b00000000; //All Degital PORT ANSELH = 0b00000000; //All Degital PORT // ***************************** // 2.Program main // ***************************** while(1){ for(lp=0;lp<0x100;lp++){ PORTC = (unsigned char)lp; Timer(); } } } //****************************************************************************************** // Program : Wait_1ms // Title : // Input : // Output : //****************************************************************************************** void Wait_1ms(unsigned int n) { unsigned int lp; for(lp=0;lp: Timer1 Input Clock Prescale Select bits // 11 = 1:8 Prescale value // 10 = 1:4 Prescale value // 01 = 1:2 Prescale value // 00 = 1:1 Prescale value //* T1CON(3) T1OSCEN: Timer1 Oscillator Enable bit // 1 = Timer1 oscillator is enabled // 0 = Timer1 oscillator is shut off // The oscillator inverter and feedback resistor are turned off to eliminate power drain. //* T1CON(2) T1SYNC: Timer1 External Clock Input Synchronization Select bit // When TMR1CS = 1: // 1 = Do not synchronize external clock input // 0 = Synchronize external clock input // When TMR1CS = 0: // This bit is ignored. Timer1 uses the internal clock when TMR1CS = 0. //* T1CON(1) TMR1CS: Timer1 Clock Source Select bit // 1 = External clock from the T13CKI pin (on the rising edge) // 0 = Internal clock (FOSC/4) //* T1CON(0) bit 0 TMR1ON: Timer1 On bit // 1 = Enables Timer1 // 0 = Stops Timer1 // ******************************************************* T1CON = 0b10000001; // 16-bit Read/Write Mode, 1:8 Prescale value // ******************************************************* // 2.Define TMR1 Register // Caution(16-bit Read/Write Mode) !!!!: // (a)Writing to TMR1H does not directly affect Timer1. // Instead, the high byte of Timer1 is updated with the contents of TMR1H when a write occurs to TMR1L. // This allows all 16 bits of Timer1 to be updated at once. // (b)A read from TMR1L will load the contents of the high byte of Timer1 into the Timer1 high byte buffer. // This provides the user with the ability to accurately read all 16 bits of Timer1 without the need to // determine whether a read of the high byte, followed by a read of the low byte, has become invalid due // to a rollover or carry between reads. // ******************************************************* // TMR1 data ( OSC:12MHz, 4X PLLON, 1:8 Prescale value, 0.01[S];100Hz ) // 10mS(100Hz): 12MHz * 4(PLLON) / 4(PIC) / 8(Prescale) / 100(100Hz)==> 0d15,000(Count) ==> 0x3A98(Count) // TMR1 = 0xFFFF - 0x3A98 ==> 0xC567 // 10mS(100Hz): 12MHz * 4(PLLON) / 4(PIC) / 1(Prescale) / 1000(1000Hz)==> 0d12,000(Count) ==> 0x2EE0(Count) // TMR1 = 0xFFFF - 0x2EE0 ==> 0xD11F // TMR1H = 0xD1; TMR1L = 0x1F; // ******************************************************* // 3.Timer // ******************************************************* PIR1bits.TMR1IF = 0; while(1){ if(PIR1bits.TMR1IF != 0 )break; } }