| 我想测一下28027板子的XCLKOUT信号的波形，可是一直是高电平。 我用的官方例程定时器的例子，其中有初始化： void InitPeripheralClocks(void) { EALLOW; // LOSPCP prescale register settings, normally it will be set to default values GpioCtrlRegs.GPAMUX2.bit.GPIO18 = 3; // GPIO18 = XCLKOUT SysCtrlRegs.LOSPCP.all = 0x0002; // XCLKOUT to SYSCLKOUT ratio. By default XCLKOUT = 1/4 SYSCLKOUT SysCtrlRegs.XCLK.bit.XCLKOUTDIV=2; // Set XCLKOUT = SYSCLKOUT/1 // Peripheral clock enables set for the selected peripherals. // If you are not using a peripheral leave the clock off // to save on power. // // Note: not all peripherals are available on all 2802x derivates. // Refer to the datasheet for your particular device. // // This function is not written to be an example of efficient code. SysCtrlRegs.PCLKCR0.bit.ADCENCLK = 1; // ADC SysCtrlRegs.PCLKCR3.bit.COMP1ENCLK = 1; // COMP1 SysCtrlRegs.PCLKCR3.bit.COMP2ENCLK = 1; // COMP2 SysCtrlRegs.PCLKCR3.bit.CPUTIMER0ENCLK = 1; // CPU Timer-0 SysCtrlRegs.PCLKCR3.bit.CPUTIMER1ENCLK = 1; // CPU Timer-1 SysCtrlRegs.PCLKCR3.bit.CPUTIMER2ENCLK = 1; // CPU Timer-2 SysCtrlRegs.PCLKCR1.bit.ECAP1ENCLK = 1; // eCAP1 SysCtrlRegs.PCLKCR1.bit.EPWM1ENCLK = 1; // EPWM1 SysCtrlRegs.PCLKCR1.bit.EPWM2ENCLK = 1; // EPWM2 SysCtrlRegs.PCLKCR1.bit.EPWM3ENCLK = 1; // EPWM3 SysCtrlRegs.PCLKCR1.bit.EPWM4ENCLK = 1; // EPWM4 SysCtrlRegs.PCLKCR3.bit.GPIOINENCLK = 1; // GPIO SysCtrlRegs.PCLKCR0.bit.HRPWMENCLK=1; // HRPWM SysCtrlRegs.PCLKCR0.bit.I2CAENCLK = 1; // I2C SysCtrlRegs.PCLKCR0.bit.SCIAENCLK = 1; // SCI-A SysCtrlRegs.PCLKCR0.bit.SPIAENCLK = 1; // SPI-A SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 1; // Enable TBCLK within the EPWM EDIS; } // LOSPCP prescale register settings, normally it will be set to default values GpioCtrlRegs.GPAMUX2.bit.GPIO18 = 3; // GPIO18 = XCLKOUT SysCtrlRegs.LOSPCP.all = 0x0002; // XCLKOUT to SYSCLKOUT ratio. By default XCLKOUT = 1/4 SYSCLKOUT SysCtrlRegs.XCLK.bit.XCLKOUTDIV=2; // Set XCLKOUT = SYSCLKOUT/1 上面两句就是初始化XCLKOUT的，GPIO18是XCLKOUT功能，它的频率等于SYSCLKOUT。 为什么没有波形呢？请高手指教，谢谢！ |
