PIC16F15323單片機 （中斷與定時器Timer0）

• 1 基本原理
• 2 實現代碼

開發環境選擇的是 MPLAB X IDE v5.50和 xc8-v2.32-full-install-windows-x64-installer。

1 基本原理

2 實現代碼

主要根據FIGURE 25-1 和中斷的邏輯框圖來編寫代碼，這樣代碼的可讀性強，也便于理解。但有些寄存器在框圖中可能沒有說明，所以也需要仔細閱讀定時器0的官方文檔，即基本原理部分。

/** File: timer0.c* Author: Sure*---------------系統功能：中斷 定時器0* Created on October 21, 2021, 7:48 PM*/// PIC16F15323 Configuration Bit Settings // -----------熔絲配置-------------- // 'C' source line config statements // CONFIG1 #pragma config FEXTOSC = ECH // External Oscillator mode selection bits (EC above 8MHz; PFM set to high power) #pragma config RSTOSC = EXT1X // Power-up default value for COSC bits (EXTOSC operating per FEXTOSC bits) #pragma config CLKOUTEN = OFF // Clock Out Enable bit (CLKOUT function is disabled; i/o or oscillator function on OSC2) #pragma config CSWEN = OFF // Clock Switch Enable bit (Writing to NOSC and NDIV is allowed) #pragma config FCMEN = OFF // Fail-Safe Clock Monitor Enable bit (FSCM timer enabled)// CONFIG2 #pragma config MCLRE = OFF // Master Clear Enable bit (MCLR pin is Master Clear function) #pragma config PWRTE = OFF // Power-up Timer Enable bit (PWRT disabled) #pragma config LPBOREN = OFF // Low-Power BOR enable bit (ULPBOR disabled) #pragma config BOREN = OFF // Brown-out reset enable bits (Brown-out Reset Enabled, SBOREN bit is ignored) #pragma config BORV = LO // Brown-out Reset Voltage Selection (Brown-out Reset Voltage (VBOR) set to 1.9V on LF, and 2.45V on F Devices) #pragma config ZCD = OFF // Zero-cross detect disable (Zero-cross detect circuit is disabled at POR.) #pragma config PPS1WAY = OFF // Peripheral Pin Select one-way control (The PPSLOCK bit can be cleared and set only once in software) #pragma config STVREN = OFF // Stack Overflow/Underflow Reset Enable bit (Stack Overflow or Underflow will cause a reset)// CONFIG3 #pragma config WDTCPS = WDTCPS_31// WDT Period Select bits (Divider ratio 1:65536; software control of WDTPS) #pragma config WDTE = OFF // WDT operating mode (WDT enabled regardless of sleep; SWDTEN ignored) #pragma config WDTCWS = WDTCWS_7// WDT Window Select bits (window always open (100%); software control; keyed access not required) #pragma config WDTCCS = SC // WDT input clock selector (Software Control)// CONFIG4 #pragma config BBSIZE = BB512 // Boot Block Size Selection bits (512 words boot block size) #pragma config BBEN = OFF // Boot Block Enable bit (Boot Block disabled) #pragma config SAFEN = OFF // SAF Enable bit (SAF disabled) #pragma config WRTAPP = OFF // Application Block Write Protection bit (Application Block not write protected) #pragma config WRTB = OFF // Boot Block Write Protection bit (Boot Block not write protected) #pragma config WRTC = OFF // Configuration Register Write Protection bit (Configuration Register not write protected) #pragma config WRTSAF = OFF // Storage Area Flash Write Protection bit (SAF not write protected) #pragma config LVP = OFF // Low Voltage Programming Enable bit (Low Voltage programming enabled. MCLR/Vpp pin function is MCLR.)// CONFIG5 #pragma config CP = OFF // UserNVM Program memory code protection bit (UserNVM code protection disabled)// #pragma config statements should precede project file includes. // Use project enums instead of #define for ON and OFF.#include <xc.h>//引用頭文件 //#include"delay.h"//調用延時子函數/*-----------宏定義--------------*/ #define uint unsigned int #define uchar unsigned char #define V0 RA0uint i;/*-----------子函數聲明--------------*//*-----------主函數--------------*/ void main(void) {// The corresponding data direction register is TRISA. // Setting a TRISA bit (= 1) will make the corresponding PORTA pi an input. // Clearing a TRISA bit (= 0) will make the corresponding PORTA pin an output. TRISA=0xfe; //設置數據方向 RA7-RA1為輸入，RA0為輸出// 1 = Port pin is > VIH，即高電平 ; 0 = Port pin is < VIL ,即低電平PORTA=0X00; //端口賦初值/********定時器TMR0初始化**********///The T0CS<2:0> bits of the T0CON1 register are used to select the clock source for Timer0. // Clock Source Selection: 010 = FOSC/4 T0CS2=0; //TMR0時鐘源選擇位，TMR0的時鐘源 選擇 內部指令周期（fosc/4）T0CS1=1;T0CS0=0;// There are 16 prescaler options for Timer0 ranging in powers of two from 1:1 to// 1:32768. The prescaler values are selected using the T0CKPS<3:0> bits of the T0CON1 register.T0CKPS3=0; // 預分頻 1:1 ，對應的編碼為0000T0CKPS2=0; T0CKPS1=0;T0CKPS0=0;// T0ASYNC: TMR0 Input Asynchronization Enable bit// 1 = The input to the TMR0 counter is not synchronized to system clocks// 0 = The input to the TMR0 counter is synchronized to FOSC/4T0ASYNC=0; // 同步時鐘模式// T016BIT : Timer0 Operating as 16-bit Timer Select bit// 1 = Timer0 is a 16-bit timer. 0 = Timer0 is an 8-bit timerT016BIT=1; // 計數寄存器16位// 2The Timer0 interrupt flag bit (TMR0IF) is set when either of the following conditions occur:// 8-bit TMR0L matches the TMR0H value. 16-bit TMR0 rolls over from ‘FFFFh’// The Timer1 module is a 16-bit timer/counter consisting of two 8-bit registers (TMR1H and TMR1L)// which are readable and writable. //16位計數寄存器給初值，在這里沒有考慮中斷所造成的時鐘延遲13個指令周期TMR0H=(65536-100)/256; // 定時100us*8(八分頻)，計數寄存器就會溢出TMR0L=(65536-100)%256; // There are 16 postscaler options for Timer0 ranging from 1:1 to 1:16.// The postscaler values are selected using the T0OUTPS<3:0> bits of the T0CON0 register. T0OUTPS3=0; // 后分頻器 0000 = 1:1 PostscalerT0OUTPS2=0;T0OUTPS1=0;T0OUTPS0=0;// Timer0 Enable bit. 1 = The module is enabled and operating// 0 = The module is disabled and in the lowest power modeT0EN=1; // 打開定時器0// This overflow sets bit TMR0IF(T0IF). 通過T0IF=1，來說明計數寄存器溢出了TMR0IF=0; //TMR0的溢出中斷標志位 清零，從而計數寄存器滿的時候，T0IF產生一個上升沿。//If Timer0 interrupts are enabled (TMR0IE bit of the PIE0 register = 1), the CPU will be interrupted TMR0IE=1; // 打開定時器0的使能位//******************** 開全局中斷設置//定時器T0設置了中斷允許，此處要開全局中斷GIE=1; // 中斷總允許控制位 置一while(1) // 死循環，單片機初始化后，就一直運行這個死循環{}}/*************中斷服務程序***************/ // void __interrupt(irq(TMR0,TMR1),base(0x100)) timerIsr(void) // 文檔里可以查到要用 void __interrupt() ISR(void) 的形式添加中斷程序 //void interrupt ISR(void)//PIC單片機的所有中斷都是這樣一個入口 void __interrupt() ISR(void)//PIC單片機的所有中斷都是這樣一個入口 {// The TMR0 interrupt is generated(T0IF==1) when the TMR0 register overflows from FFFFh to 0000h.// 計數器寄存器由全1變為全0的時候，T0IF==1.if(TMR0IF==1) //需要進一步判斷是否為T0中斷 {//定時器中斷后，要重置初值，以備下次中斷TMR0H=(65536-100)/256; TMR0L=(65536-100)%256; // Bit TMR0IF must be cleared in software by the Timer0 module Interrupt Service Routine// before re-enabling this interrupt. 解釋了為什么要清零//溢出中斷標志位清零 只有T0IF出現上升沿，才會產生中斷，所以中斷發生之后要清零。 TMR0IF=0; // 執行中斷處理程序，也就是中斷產生了，我們想要執行什么功能if(++i>250) //2ms中斷一次，再計次250次后就是500ms{i=0;V0=!V0; // 取反 實現一秒的閃爍}} }

總結

以上是生活随笔為你收集整理的PIC16F15323单片机 （中断与定时器Timer0）的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。