#if PLL_EN == 0 /* Not use PLL 不使用PLL */
SysCtlClockSet(CCLK_DIV | SYSCTL_USE_OSC | SYSCTL_OSC_MAIN | EXT_CLK);
#if TARGET_LED1_EN > 0
#define LED1_SYSCTL SYSCTL_PERIPH_GPIOB /* System control of LED1 */
#define LED1_GPIO_PORT GPIO_PORTB_BASE /* IO port of LED1 */
#define LED1_PIN GPIO_PIN_6 /* Pin number of LED1 */
#endif