TI中文支持网那这个CPU clock speed是什么意思？
Susan Yang：
在
// DO NOT MODIFY THIS LINE.
#define DELAY_US(A) DSP28x_usDelay(((((long double) A * 1000.0L) / (long double)CPU_RATE) – 9.0L) / 5.0L)
中
A对应需要延迟的时间，单位是us，L代表ns
CPU clock speed 代表主频即SYSCLKOUT
而 CPU_RATE是CPU clock speed的倒数
如
Specify the clock rate of the CPU (SYSCLKOUT) in nS.Take into account the input clock frequency and the PLL multiplierselected in step 1.Use one of the values provided, or define your own.The trailing L is required tells the compiler to treatthe number as a 64-bit value.Only one statement should be uncommented.Example 1:150 MHz devices:CLKIN is a 30MHz crystal.In step 1 the user specified PLLCR = 0xA for a150Mhz CPU clock (SYSCLKOUT = 150MHz).In this case, the CPU_RATE will be 6.667LUncomment the line:#define CPU_RATE6.667LExample 2:100 MHz devices:CLKIN is a 20MHz crystal.In step 1 the user specified PLLCR = 0xA for a100Mhz CPU clock (SYSCLKOUT = 100MHz).In this case, the CPU_RATE will be 10.000LUncomment the line:#define CPU_RATE10.000L-----------------------------------------------------------------------------*/#define CPU_RATE6.667L// for a 150MHz CPU clock speed (SYSCLKOUT)//#define CPU_RATE7.143L// for a 140MHz CPU clock speed (SYSCLKOUT)//#define CPU_RATE8.333L// for a 120MHz CPU clock speed (SYSCLKOUT)//#define CPU_RATE10.000L// for a 100MHz CPU clock speed (SYSCLKOUT)//#define CPU_RATE13.330L// for a 75MHz CPU clock speed (SYSCLKOUT)//#define CPU_RATE20.000L// for a 50MHz CPU clock speed(SYSCLKOUT)//#define CPU_RATE33.333L// for a 30MHz CPU clock speed(SYSCLKOUT)//#define CPU_RATE41.667L// for a 24MHz CPU clock speed(SYSCLKOUT)//#define CPU_RATE50.000L// for a 20MHz CPU clock speed(SYSCLKOUT)//#define CPU_RATE66.667L// for a 15MHz CPU clock speed(SYSCLKOUT)//#define CPU_RATE100.000L// for a 10MHz CPU clock speed(SYSCLKOUT)
那这个CPU clock speed是什么意思？
mangui zhang：
回复 Susan Yang:
你这个讲解非常详细学习&感谢
那这个CPU clock speed是什么意思？
Susan Yang：
回复 mangui zhang:
希望能帮到大家
那这个CPU clock speed是什么意思？
user5831357：
回复 Susan Yang:
谢谢您的答复
