尝试在TM4C123微控制器的PB4上初始化PWM
正如标题所述,我正在尝试使用Keil作为IDE在TM4C123微控制器上初始化PB4的PWM。到目前为止,我已经能够初始化PB6和PB7,但我不确定PB4为什么不能工作。你们知道我做错了什么吗?提前感谢你的帮助。我已经发布了初始化端口B6的工作代码和不适用于端口B4的代码尝试在TM4C123微控制器的PB4上初始化PWM,c,keil,pwm,C,Keil,Pwm,正如标题所述,我正在尝试使用Keil作为IDE在TM4C123微控制器上初始化PB4的PWM。到目前为止,我已经能够初始化PB6和PB7,但我不确定PB4为什么不能工作。你们知道我做错了什么吗?提前感谢你的帮助。我已经发布了初始化端口B6的工作代码和不适用于端口B4的代码 // PWM clock rate = processor clock rate/SYSCTL_RCC_PWMDIV // = BusClock/16 // = 80
// PWM clock rate = processor clock rate/SYSCTL_RCC_PWMDIV
// = BusClock/16
// = 80 MHz/16 = 5 MHz
// Output on PB7/M0PWM1
void PWM0B4_Init(uint16_t period, uint16_t duty)
{
volatile unsigned long delay;
SYSCTL_RCGCPWM_R |= 0x01; // 1) activate PWM0
SYSCTL_RCGCGPIO_R |= 0x02; // 2) activate port B
// delay = SYSCTL_RCGCGPIO_R; // allow time to finish activating
while((SYSCTL_PRGPIO_R&0x02) == 0){};
GPIO_PORTB_AFSEL_R |= 0x10; // enable alt funct on PB4
GPIO_PORTB_PCTL_R &= ~0x000F000; // configure PB4 as M0PWM2
GPIO_PORTB_PCTL_R |= 0x0004000;
GPIO_PORTB_AMSEL_R &= ~0x10; // disable analog functionality on PB4
GPIO_PORTB_DEN_R |= 0x10; // enable digital I/O on PB4 ** double check **
SYSCTL_RCC_R = 0x00100000 | // 3) use PWM divider
(SYSCTL_RCC_R & (~0x000C0000)); // configure for /16 divider
PWM0_1_CTL_R = 0; // 4) re-loading down-counting mode
PWM0_1_GENB_R = (PWM_1_GENB_ACTCMPBD_ONE|PWM_1_GENB_ACTLOAD_ZERO);
// PB4 goes low on LOAD
// PB4 goes high on CMPB down
PWM0_1_LOAD_R = period - 1; // 5) cycles needed to count down to 0
PWM0_1_CMPB_R = duty - 1; // 6) count value when output rises
PWM0_1_CTL_R |= 0x00000001; // 7) start PWM0
PWM0_ENABLE_R |= 0x00000004; // enable PB4/M0PWM2 **** check
}
// change duty cycle of PB4
// duty is number of PWM clock cycles output is high (2<=duty<=period-1)
void PWM0B4_Duty(uint16_t duty)
{
PWM0_1_CMPB_R = duty - 1; // 6) count value when output rises
}
void PWM0B6_Init(uint16_t period, uint16_t duty)
{
SYSCTL_RCGCPWM_R |=0x01; // 1) activate PWM0
SYSCTL_RCGCGPIO_R|=0x02; // 2) activate portB
while ((SYSCTL_PRGPIO_R&0x02) == 0) {};
GPIO_PORTB_AFSEL_R |= 0x40; // enable alt funct on PB6
GPIO_PORTB_PCTL_R &= ~0x0F000000; // configure PB6 as PWM0
GPIO_PORTB_PCTL_R |= 0x04000000;
GPIO_PORTB_AMSEL_R &= ~0x40; // disable analog functionality on PB6
GPIO_PORTB_DEN_R |= 0x40; // enable digital I/O on PB6
SYSCTL_RCC_R = 0x00100000 | // 3) use PWM divider
(SYSCTL_RCC_R & (~0x000C0000)); // configure for /16 divider to C
PWM0_0_CTL_R = 0; // 4) re-loading down-counting mode
PWM0_0_GENA_R = 0xC8; // low on LOAD, high on CMPA down
// PB6 goes low on LOAD
// PB6 goes high on CMPA down
PWM0_0_LOAD_R = period - 1; // 5) cycles needed to count down to 0
PWM0_0_CMPA_R = duty - 1; // 6) count value when output rises
PWM0_0_CTL_R |= 0x00000001; // 7) start PWM0
PWM0_ENABLE_R |= 0x00000001; // enable PB6/M0PWM0
}
// change duty cycle of PB6
// duty is number of PWM clock cycles output is high (2<=duty<=period-1)
void PWM0B6_Duty(uint16_t duty)
{
PWM0_0_CMPA_R = duty - 1; // 6) count value when output rises
}
//PWM时钟速率=处理器时钟速率/SYSCTL\u RCC\u PWMDIV
//=总线时钟/16
//=80 MHz/16=5 MHz
//PB7/M0PWM1上的输出
无效PWM0B4初始(有效期,有效期)
{
易失性无符号长延迟;
SYSCTL_RCGCPWM_R |=0x01;//1)激活PWM0
SYSCTL_RCGCGPIO|u R |=0x02;//2)激活端口B
//delay=SYSCTL\u RCGCGPIO\u R;//允许时间完成激活
而((SYSCTL_PRGPIO_R&0x02)==0{};
GPIO_PORTB_AFSEL_R |=0x10;//在PB4上启用alt函数
GPIO_PORTB_PCTL_R&=~0x000F000;//将PB4配置为M0PWM2
GPIO_端口B_PCTL|u R |=0x0004000;
GPIO_PORTB_AMSEL_R&=~0x10;//禁用PB4上的模拟功能
GPIO_端口B_DEN_R |=0x10;//在PB4上启用数字I/O**双重检查**
SYSCTL_RCC_R=0x00100000 |//3)使用PWM分压器
(SYSCTL_RCC_R&(~0x000c000));//为/16除法器配置
PWM0_1_CTL_R=0;//4)重新加载向下计数模式
PWM0_1_GENB_R=(PWM_1_GENB_ACTCMPBD_ONE | PWM_1_GENB_ACTLOAD_ZERO);
//PB4负载过低
//PB4在CMPB下降时变高
PWM0_1_LOAD_R=周期-1;//5)个周期需要倒计时到0
PWM0_1_CMPB_R=占空比-1;//6)输出上升时的计数值
PWM0_1_CTL|=0x00000001;//7)启动PWM0
PWM0_ENABLE_R|=0x00000004;//启用PB4/M0PWM2****检查
}
//改变PB4的占空比
//占空比是PWM时钟周期数输出很高(2很抱歉,这就是我们在学校一直采用的格式,我应该做些什么来提高可读性?哦,好的,让我来解决,谢谢你确定PWM0_1*
是正确的吗?据我所知,数据表上说PB4使用模块0 PWM 2。(应该不是PWM0_2*
?)我最初使用的是PWM0_2,但在数据表中,它还说PB4由模块0 PWM发生器1控制。这就是我使用PWM0_1的原因。您可以发布PB6或PB7的工作代码吗?我不知道您使用的是µC。您确定启用数字IO模式不会禁用alt功能吗?您可以先设置数字IO并禁用模拟你能启用alt功能吗?