PIC24F16KL402开发板使用笔记四: Timer1计时器例程

配置Timer1 的操作：
1. 将TON 位置1 （= 1）。
2. 使用TCKPS<1:0> 位选择定时器预分频比。
3. 使用TCS 和TGATE 位设置时钟和门控模式。
4. 将TSYNC位置1或清零来配置同步或异步操作。
5. 将定时器的周期值装入PR1 寄存器。
6. 如果需要中断，将中断允许位T1IE 置1。使用中
断优先级位T1IP<2:0> 来设置中断优先级。

timer1的代码：

/*
* File: ??mainXC16.c
* Author: Administrator
*
* Created on 2015?3?23?, ??10:20
*/
#include "xc.h"
_FBS
(
BWRP_OFF & // Boot Segment Write Protect (Disabled)
BSS_OFF // Boot segment Protect (No boot flash segment)
)
//_FGS
//(
// GWRP_OFF & // General Segment Flash Write Protect (General segment may be written)
// GSS0_OFF // General Segment Code Protect (No Protection)
//)
_FOSCSEL
(
FNOSC_FRC & // Oscillator Select (8MHz FRC with Postscaler (FRCDIV))
// SOSCSRC_ANA & // SOSC Source Type (Analog Mode for use with crystal)
// LPRCSEL_HP & // LPRC Power and Accuracy (High Power/High Accuracy)
IESO_ON // Internal External Switch Over bit (Internal External Switchover mode enabled (Two-speed Start-up enabled))
)
_FOSC
(
// POSCMD_HS & // Primary Oscillator Mode (Primary oscillator disabled)
OSCIOFNC_ON & // CLKO Enable Configuration bit (CLKO output signal enabled)
POSCFREQ_MS & // Primary Oscillator Frequency Range Configuration bits (Primary oscillator/external clock frequency between 100kHz to 8MHz)
SOSCSEL_SOSCHP &// SOSC Power Selection Configuration bits (Secondary Oscillator configured for high-power operation)
FCKSM_CSECME // Clock Switching and Monitor Selection (Clock Switching and Fail-safe Clock Monitor Enabled)
)
_FWDT
(
WDTPS_PS32768 & // Watchdog Timer Postscale Select bits (1:32768)
FWPSA_PR128 & // WDT Prescaler bit (WDT prescaler ratio of 1:128)
FWDTEN_OFF & // Watchdog Timer Enable bits (WDT disabled in hardware; SWDTEN bit disabled)
WINDIS_OFF // Windowed Watchdog Timer Disable bit (Standard WDT selected (windowed WDT disabled))
)
// Warning:
// Always enable MCLRE_ON config bit setting so that the MCLR pin function will
// work for low-voltage In-Circuit Serial Programming (ICSP). The Microstick
// programming circuitry only supports low-voltage ICSP. If you disable MCLR pin
// functionality, a high-voltage ICSP tool will be required to re-program the
// part in the future.
_FPOR
(
BOREN_BOR3 & // Brown-out Reset Enable bits (Enabled in hardware; SBOREN bit disabled)
PWRTEN_ON & // Power-up Timer Enable (PWRT enabled)
I2C1SEL_PRI & // Alternate I2C1 Pin Mapping bit (Default SCL1/SDA1 Pins for I2C1)
BORV_V18 & // Brown-out Reset Voltage bits (Brown-out Reset at 1.8V)
MCLRE_ON // MCLR Pin Enable bit (RA5 input disabled; MCLR enabled)
)
_FICD
(
ICS_PGx3 // ICD Pin Placement Select (EMUC/EMUD share PGC3/PGD3)
)
int main(void) {
TRISAbits.TRISA0 = 0;
LATAbits.LATA0 = 1;
//Init timer1.
T1CON = 0x00; //Stops the Timer1 and reset control reg.
T1CONbits.TCKPS0 =1;
T1CONbits.TCKPS1 =0;
TMR1 = 0x00; //Clear contents of the timer register
PR1 = 0x000f; //Load the Period register with the value 0xFFFF
IPC0bits.T1IP = 0x01; //Setup Timer1 interrupt for desired priority level.
IFS0bits.T1IF = 0;
IEC0bits.T1IE = 1;
T1CONbits.TON = 1;
while(1)
{
;
}
return 0;
}
void __attribute__((interrupt, shadow, no_auto_psv)) _T1Interrupt(void)
{
LATAbits.LATA0 ^= 1;
/* Interrupt Service Routine code goes here. */
IFS0bits.T1IF = 0; //Reset Timer1 interrupt flag and Return from ISR
}