f28335的ecap测量方波的周期 求教 谢谢高手们

#include "DSP2833x_Device.h" // DSP2833x Headerfile Include File
#include "DSP2833x_Examples.h" // DSP2833x Examples Include File
// Prototype statements for functions found within this file.
interrupt void ecap1_isr(void);
//interrupt void ecap5_isr(void);
void InitECapture1(void);
// Global variables used in this example
Uint32 ECap1IntCount;
Uint32 t1,t2,t3,t4,T1,T2;
void main(void)
{
InitSysCtrl();
//ECAP 引脚初始化
InitECap1Gpio();
// InitECap5Gpio();
DINT;
InitPieCtrl();
// Disable CPU interrupts and clear all CPU interrupt flags:
IER = 0x0000;
IFR = 0x0000;
InitPieVectTable();
EALLOW; // This is needed to write to EALLOW protected registers
//中断响应函数
PieVectTable.ECAP1_INT = &ecap1_isr;
// PieVectTable.ECAP5_INT = &ecap5_isr;
EDIS; // This is needed to disable write to EALLOW protected registers
//ECAP 配置
InitECapture1();
ECap1IntCount = 0;
// Enable CPU INT4 which is connected to ECAP1-4 INT:
IER |= M_INT4;
// Enable eCAP INTn in the PIE: Group 4 interrupt 1-6
PieCtrlRegs.PIEIER4.bit.INTx1 = 1;
// Enable global Interrupts and higher priority real-time debug events:
EINT; // Enable Global interrupt INTM
ERTM; // Enable Global realtime interrupt DBGM
// Step 6. IDLE loop. Just sit and loop forever (optional):
SysCtrlRegs.PCLKCR1.bit.ECAP1ENCLK=1;
for(;;)
{
asm("NOP");
}
}
void InitECapture1()
{
ECap1Regs.ECEINT.all = 0x0000; // Disable all capture interrupts
ECap1Regs.ECCLR.all = 0xFFFF; // Clear all CAP interrupt flags
ECap1Regs.ECCTL1.bit.CAPLDEN = 0; // Disable CAP1-CAP4 register loads
ECap1Regs.ECCTL2.bit.TSCTRSTOP = 0; // Make sure the counter is stopped
// Configure peripheral registers
ECap1Regs.ECCTL2.bit.CAP_APWM = 0; // ECAP模式，另一种模式是APWM
ECap1Regs.ECCTL2.bit.CONT_ONESHT = 0; // One shot
ECap1Regs.ECCTL2.bit.STOP_WRAP = 3; // Stop at 1 events
ECap1Regs.ECCTL1.bit.CAP1POL = 0; // 默认配置上升沿触发
ECap1Regs.ECCTL1.bit.CAP2POL = 1; // Falling edge
ECap1Regs.ECCTL1.bit.CAP3POL = 0; // Rising edge
ECap1Regs.ECCTL1.bit.CAP4POL = 1; // Falling edge
ECap1Regs.ECCTL1.bit.CTRRST1 = 0; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST2 = 0; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST3 = 0; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST4 = 1; // Difference operation
ECap1Regs.ECCTL2.bit.SYNCI_EN = 0; // Disable sync
ECap1Regs.ECCTL2.bit.SYNCO_SEL = 2; // Disable sync out
ECap1Regs.ECCTL1.bit.PRESCALE = 0; //1分频（不分频）
ECap1Regs.ECCTL1.bit.CAPLDEN = 1; // Enable CAP1-CAP4 register loads
ECap1Regs.ECCTL2.bit.TSCTRSTOP = 1; // Start Counter
// ECap1Regs.ECCTL2.bit.REARM = 1; // arm one-shot
ECap1Regs.ECEINT.bit.CEVT4 = 1; // CEVENT = interrupt
}
interrupt void ecap1_isr(void)
{
ECap1IntCount++;
t1 = ECap1Regs.CAP1;
t2 = ECap1Regs.CAP2;
t3 = ECap1Regs.CAP3;
t4 = ECap1Regs.CAP4;
T1=t3-t1;
T2=t4-t2;
ECap1Regs.ECCLR.bit.CEVT4 = 1; // CEVENT events = interrupt
ECap1Regs.ECCLR.bit.INT = 1;
// ECap1Regs.ECCTL2.bit.REARM = 1;
// Acknowledge this interrupt to receive more interrupts from group 4
PieCtrlRegs.PIEACK.all = PIEACK_GROUP4;
}
用f28335测量外接脉冲的频率，请问这程序哪里有问题呀？ 设置断点查看变量值 为什么ECap1Regs.CAP1 ECap1Regs.CAP2 ECap1Regs.CAP3 ECap1Regs.CAP4的值都一样啊 还有ECap1Regs.CAP3-ECap1Regs.CAP1的值就是一个周期 有错么？ 谢谢指导