为什么我这样初始化后 系统时钟很慢!我查看MCG的寄存器与例程的寄存器值是一样的 但是为什么慢的不行不行!
SIM_SCGC5 |= (uint32_t)0x0200UL; /* Enable clock gate for ports to enable pin routing */
SIM_CLKDIV1 = (uint32_t)0x00010000UL; /* Update system prescalers */
PORTA_PCR(3) &= (uint32_t)~0x01000700UL;
PORTA_PCR(4) &= (uint32_t)~0x01000700UL;
OSC0_CR = (uint8_t)0x89U;
MCG_C2 = (uint8_t)0x24U;
MCG_C1 = (uint8_t)0x1AU;
MCG_C4 &= (uint8_t)~(uint8_t)0xE0U;
MCG_C4 |= (1 << 5); |