我用的单片机芯片是TM4C123AH6PM的，我要做的课题是用它来控制一个四相六线的步进电动机，导师说需要写出它的PWM和Timer的程序，我是参考的之前的BLDC里的PWM语言程序来写stepper里的PWM可是再对照Data sheet后发现，当写到（打？的那部分，说明书里没有相对应的数值）说明书那一部分（在第555页
）附上，电路图也附上，谢谢帮忙。可以确定的是，PWM1H4和PWM1L4分别对应的管脚是
void PWMClass::initAsPWM0()
{
SYSCTL_PERIPH_PWM = SYSCTL_PERIPH_PWM0;
SYSCTL_PERIPH_GPIO_CH_A = SYSCTL_PERIPH_GPIOB;
SYSCTL_PERIPH_GPIO_CH_B = SYSCTL_PERIPH_GPIOC;
SYSCTL_PERIPH_GPIO_CH_C = SYSCTL_PERIPH_GPIOG;
SYSCTL_PERIPH_GPIO_CH_D = SYSCTL_PERIPH_GPIOC;// 参考的电路图，PWM1H4,L4的位置所在Pc6和Pc7。
GPIO_CFG_H1 = GPIO_PB6_M0PWM0; // Configure PWM1H1 pin multiplexer
GPIO_CFG_L1 = GPIO_PB7_M0PWM1; // Configure PWM1L1 pin multiplexer
GPIO_CFG_H2 = GPIO_PC4_M0PWM6; // Configure PWM1H2 pin multiplexer
GPIO_CFG_L2 = GPIO_PC5_M0PWM7; // Configure PWM1L2 pin multiplexer
GPIO_CFG_H3 = GPIO_PG4_M0PWM4; // Configure PWM1H3 pin multiplexer
GPIO_CFG_L3 = GPIO_PG5_M0PWM5; // Configure PWM1L3 pin multiplexer
GPIO_CFG_H4 = GPIO_PC6_？？？？？？？？？？？？？？？？？？？; // Configure PWM1H4 pin multiplexer
GPIO_CFG_L4 = GPIO_PC7_？？？？？？？？？？？？？？？？？？？？; // Configure PWM1L4 pin multiplexer
