TI中文支持网1.28335的ecap捕获外部信号时，外部信号和dsp是不是不能公地啊？
2.我用信号源给28335的GPIO24脚加了一个频率为1KHz的方波信号，采用28335的差分捕获模式，我在中断处理函数中定义了一个period1,2,3的变量，然后period1=ECapRegs.CAP1;period2=ECapRegs.CAP2;period3=ECapRegs.CAP3;按理来讲这三个变量的值应该不会变动的，可是我实验的结果确波动很大。
//ecap初始化配置函数
void InitECapture()
{
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.CONT_ONESHT = 1; // One-shot
ECap1Regs.ECCTL2.bit.STOP_WRAP = 3; // Stop at 4 events
ECap1Regs.ECCTL1.bit.CAP1POL = 1; // Falling edge
ECap1Regs.ECCTL1.bit.CAP2POL = 0; // Rising edge
ECap1Regs.ECCTL1.bit.CAP3POL = 1; // Falling edge
ECap1Regs.ECCTL1.bit.CAP4POL = 0; // Rising edge
ECap1Regs.ECCTL1.bit.CTRRST1 = 1; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST2 = 1; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST3 = 1; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST4 = 1; // Difference operation
ECap1Regs.ECCTL2.bit.SYNCI_EN = 1; // Enable sync in
ECap1Regs.ECCTL2.bit.SYNCO_SEL = 0; // Pass through
ECap1Regs.ECCTL1.bit.CAPLDEN = 1; // Enable capture units
ECap1Regs.ECCTL2.bit.TSCTRSTOP = 1; // Start Counter
ECap1Regs.ECCTL2.bit.REARM = 1; // arm one-shot
ECap1Regs.ECCTL1.bit.CAPLDEN = 1; // Enable CAP1-CAP4 register loads
ECap1Regs.ECEINT.bit.CEVT4 = 1; // 4 events = interrupt
}
//中断处理函数
interrupt void ecap1_isr(void)
{
ECap1IntCount++;
period1=ECap1Regs.CAP1;
period2=ECap1Regs.CAP2;
period3=ECap1Regs.CAP3;
ECap1PassCount++;
ECap1Regs.ECCLR.bit.CEVT4 = 1;
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;
}
mangui zhang：
外部信号接入DSP 最好用光耦隔离一下 或者用一些整形芯片处理一下
1.28335的ecap捕获外部信号时，外部信号和dsp是不是不能公地啊？
2.我用信号源给28335的GPIO24脚加了一个频率为1KHz的方波信号，采用28335的差分捕获模式，我在中断处理函数中定义了一个period1,2,3的变量，然后period1=ECapRegs.CAP1;period2=ECapRegs.CAP2;period3=ECapRegs.CAP3;按理来讲这三个变量的值应该不会变动的，可是我实验的结果确波动很大。
//ecap初始化配置函数
void InitECapture()
{
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.CONT_ONESHT = 1; // One-shot
ECap1Regs.ECCTL2.bit.STOP_WRAP = 3; // Stop at 4 events
ECap1Regs.ECCTL1.bit.CAP1POL = 1; // Falling edge
ECap1Regs.ECCTL1.bit.CAP2POL = 0; // Rising edge
ECap1Regs.ECCTL1.bit.CAP3POL = 1; // Falling edge
ECap1Regs.ECCTL1.bit.CAP4POL = 0; // Rising edge
ECap1Regs.ECCTL1.bit.CTRRST1 = 1; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST2 = 1; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST3 = 1; // Difference operation
ECap1Regs.ECCTL1.bit.CTRRST4 = 1; // Difference operation
ECap1Regs.ECCTL2.bit.SYNCI_EN = 1; // Enable sync in
ECap1Regs.ECCTL2.bit.SYNCO_SEL = 0; // Pass through
ECap1Regs.ECCTL1.bit.CAPLDEN = 1; // Enable capture units
ECap1Regs.ECCTL2.bit.TSCTRSTOP = 1; // Start Counter
ECap1Regs.ECCTL2.bit.REARM = 1; // arm one-shot
ECap1Regs.ECCTL1.bit.CAPLDEN = 1; // Enable CAP1-CAP4 register loads
ECap1Regs.ECEINT.bit.CEVT4 = 1; // 4 events = interrupt
}
//中断处理函数
interrupt void ecap1_isr(void)
{
ECap1IntCount++;
period1=ECap1Regs.CAP1;
period2=ECap1Regs.CAP2;
period3=ECap1Regs.CAP3;
ECap1PassCount++;
ECap1Regs.ECCLR.bit.CEVT4 = 1;
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;
}
ming lei：
回复 mangui zhang:
那就不能直接共地了
