//****************************************************************************************** // PIC18F14K50 Sample Program // Project : // Program Name : // Programer : // Create date : Version 1.0 H21.12.20 // 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 mvLED(unsigned char *); void Int_Timer(void); void isr (void); // //Grobal value // volatile unsigned char G_LEDlst; volatile unsigned int G_lp_cnt; //****************************************************************************************** // Program : // Title : // Input : // Output : //****************************************************************************************** void main(void) { // ***************************** // 1.Initialized Segment // ***************************** // (1)Define I/O Port TRISA = 0xFF; TRISB = 0xFF; TRISC = 0x00; LATC = 0x00; PORTC = 0x00; // (2)Define Timer Int_Timer(); // (3)Initialize G_LEDlst = 0x01; G_lp_cnt = 0; PORTC = G_LEDlst; // ***************************** // 2.Program main (No action) // ***************************** while(1){ }; } //****************************************************************************************** // Function Name : mvLED // Title : Move LED function // Input : // Output : //****************************************************************************************** void mvLED(unsigned char *LEDlst) { if(*LEDlst == 1){ *LEDlst = 2; }else if(*LEDlst > 127){ *LEDlst = 1; }else{ *LEDlst = *LEDlst * 2; } PORTB = *LEDlst; return; } //****************************************************************************************** // Function Name : Int_Timer // Title : // Input : // Output : //****************************************************************************************** void Int_Timer(void) { // ******************************************************* // 1.Define Interrupts // Timer1 interrupt, if enabled, is generated on overflow, which is latched in the TMR1IF // interrupt flag bit of the PIR1 register. This interrupt can be enabled or disabled // by setting or clearing the TMR1IE Interrupt Enable bit of the PIE1 register. // ******************************************************* // (1)Define INTCON(INTERRUPT CONTROL)Register // INTCON(7) GIE/GIEH(Global Interrupt Enable bit) // INTCON(6) PEIE/GIEL(Peripheral Interrupt Enable bit) // 1 = Enables, 0 = Disables INTCON = INTCON | 0b11000000; // (2)Define PIR1(PERIPHERAL INTERRUPT REQUEST)Register // PIR1(0) TMR1IF(TMR1 Overflow Interrupt Flag bit) // 1 = Enables, 0 = Disables PIR1 = PIR1 | 0b00000001; // (3)Define PIE1(PERIPHERAL INTERRUPT ENABLE)Register // PIE1(0) TMR1IE(TMR1 Overflow Interrupt Enable bit) // 1 = Enables, 0 = Disables PIE1 = PIE1 | 0b00000001; // (4)Define IPR1(PERIPHERAL INTERRUPT PRIORITY REGISTER 1) // IPR1(0) TMR1IP(TMR1 Overflow Interrupt Priority bit) // 1 = High priority, 0 = Low priority // IPR1 = IPR1 | 0b00000001; IPR1 = IPR1 | 0b00000000; // ******************************************************* // 2.Define T1CON(TIMER1 CONTROL REGISTER) Register //* T1CON(7) RD16: 16-bit Read/Write Mode Enable bit // 1 = Enables register read/write of TImer1 in one 16-bit operation // 0 = Enables register read/write of Timer1 in two 8-bit operations //* T1CON(6) T1RUN: Timer1 System Clock Status bit // 1 = Main system clock is derived from Timer1 oscillator // 0 = Main system clock is derived from another source //* T1CON(5-4)T1CKPS<1:0>: 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 = 0b10110001; // 16-bit Read/Write Mode, 1:8 Prescale value // ******************************************************* // 3.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 // TMR1H = 0xC5; TMR1L = 0x67; } //****************************************************************************************** // Function Name : isr // Title : interrupt // Input : // Output : //****************************************************************************************** #pragma code Int_addr=0x8 void Int_function (void) { _asm GOTO isr _endasm } #pragma code #pragma interruptlow isr void isr (void) { // ******************* // 1.Clear Timer1 (10mS) // ******************* TMR1H = 0xC5; TMR1L = 0x67; PIR1bits.TMR1IF = 0; // ******************* // 2.Move LED (1S) // ******************* if(99 < G_lp_cnt){ mvLED(&G_LEDlst); PORTC = G_LEDlst; G_lp_cnt = 0; }else{ G_lp_cnt++; } }