can.rar

/******************************************************************************* * FileName: can.c * Dependencies: Header (.h) files if applicable, see below * Processor: PIC24HJ128GP506A * * ADDITIONAL NOTES: * * * REVISION HISTORY: * 2014/07/17 First release of source file * * *******************************************************************************/ #include "can.h" #include <p24HJ128GP506A.h> #include "common.h" #include "delay.h" #include "led.h" /******************************************************************************/ _FOSCSEL(FNOSC_FRC); // Select Internal FRC at POR _FOSC(FCKSM_CSECMD & OSCIOFNC_OFF); // Enable Clock Switching and Configure //_FOSCSEL(FNOSC_FRC); //_FOSC(FCKSM_CSECMD & OSCIOFNC_OFF & POSCMD_XT); // Clock switching enabled and fail safe clock monitor is disabled // // OSC2 pin function: OSC2 is clock output // // Primary oscillator mode: XT crystal _FWDT(FWDTEN_OFF); // Watchdog timer enabled/disabled by user software _FICD(JTAGEN_OFF & ICS_PGD2); // JTAG disabled and use ICD channel PGEC2/PGED2 /******************************************************************************/ void InitSys( void ) { RCONbits.SWDTEN = 0; // Disable watch dog timer // Configure PLL prescaler, PLL postscaler, PLL divisor PLLFBD = 41; // M = 43 CLKDIVbits.PLLPOST = 0; // N2 = 2 CLKDIVbits.PLLPRE = 0; // N1 = 2 __builtin_write_OSCCONH(0x01); // Initiate Clock Switch to Internal FRC with PLL (NOSC = 0b001) __builtin_write_OSCCONL(0x01); while( OSCCONbits.COSC != 0b001 ) Nop(); // Wait for Clock switch to occur while( OSCCONbits.LOCK != 1 ) Nop(); // Wait for PLL to lock // // Configure oscillator to operate the device at 40MHz // // Fosc= Fin*M/(N1*N2), Fcy=Fosc/2 // // Fosc= 8M*40/(2*2)=80MHz for 8MHz input clock // PLLFBD = 38; // M=40 // CLKDIVbits.PLLPOST = 0; // N1=2 // CLKDIVbits.PLLPRE = 0; // N2=2 // OSCTUN=0; // Tune FRC oscillator, if FRC is used // // Clock switching to incorporate PLL // __builtin_write_OSCCONH(0x01); // Initiate clock switch to FRC with PLL(NOSC=0b001) // __builtin_write_OSCCONL(0x01); // Start clock switching // while( OSCCONbits.COSC != 0b001 ) Nop(); // Wait for clock switch to occur // while( OSCCONbits.LOCK != 1 ) Nop(); // Wait for PLL to lock } /******************************************************************************/ void InitTimer1( void ) { T1CON = 0; // Timer1 reset IFS0bits.T1IF = 0; // Reset timer1 interrupt flag IPC0bits.T1IP = 6; // Timer1 interrupt priority level=4 IEC0bits.T1IE = 1; // Enable timer1 interrupt TMR1= 0; PR1 = 39629; // Timer1 period register=39629, resulting timing period 1ms@Fcy=39.6288MHz // PR1 = 40000; // Timer1 period register=40000, resulting timing period 1ms@Fcy=40MHz T1CONbits.TON = 1; // Enable timer1 and start the counter } /******************************************************************************/ void __attribute__((interrupt, no_auto_psv)) _T1Interrupt( void ) { static INT16U Count; IFS0bits.T1IF = 0; // Reset timer1 interrupt flag T1CONbits.TON = 0; Count++; if( Count == 500 ) { Count = 0; LEDDBG_BLINK(); // Toggle debug LED } TMR1 = 0; // Clear timer1 counter T1CONbits.TON = 1; } /******************************************************************************/ /******************************************************************************/ INT16S main( void ) { INT16U Tmp; INT08U i; Nop(); Nop(); InitSys(); // Initialize mcu primary modules: WDT/OSC/CLK and GPIOs InitTimer1(); // Initialize timer1 for period interrupts while(1) { Nop(); Nop(); } } /******************************************************************************/