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- #include "Platform.h"
- /* ---------------------------------------------------------------------------------------------------
- - 函数名称: xc_pwm_init
- - 函数功能: pwm初始化
- - 输入参数: pwm口（0或1）,占空比设置（范围0--99），周期计数器设置影响pwm信号输出频率(输出频率=pwm_clk/((period + 1)*100))
- - 创建日期: 2019-04-22
- - 作 者：陈俊伟
- ----------------------------------------------------------------------------------------------------*/
- void xc_set_pwm(uint8_t ch,uint8_t ocpy_ratio, uint16_t period)
- {
- __write_hw_reg32(PWMx_EN(ch),0x0);//暂停相应的 PWM 周期计数器和占空比计数器
- __write_hw_reg32(PWMx_P(ch),period);//pwm周期设置寄存器--等于pwm_clk/((period + 1)*100)
- __write_hw_reg32(PWMx_OCPY(ch),ocpy_ratio);//pwm占空比设置寄存器
- __write_hw_reg32(PWMx_UP(ch),0x1);//更新周期寄存器和占空比寄存器。
- __write_hw_reg32(PWMx_EN(ch),0x1);//使能相应的 PWM 周期计数器和占空比计数器
- }
- /*
- PWM 输出频率计算公式为
- Fout= 160K/((div+1)*(period + 1))
- Fout : 输出频率
- div : PWM 时钟分频比(范围0-255)
- period : PWM 周期设置 (范围0-255)
- */
- void xc_pwm_init(uint8_t ch,uint8_t ocpy_ratio, uint16_t period)
- {
-
- //注：管脚配置在Init_gpio函数中进行
-
- __write_hw_reg32(CPR_CTLAPBCLKEN_GRCTL,0x10001000); //PWM_PCLK 时钟使能
- __write_hw_reg32(CPR_PWM_CLK_CTL,0x80000000); //pwm_clk=mclk_in(32M)/(2*(0 +1))= 16M ; max output HZ 160KHZ
- // __write_hw_reg32(CPR_PWM_CLK_CTL,0x80000009); //pwm_clk=mclk_in(32M)/(2*(9+1))=1.6M
- /*
- __write_hw_reg32(CPR_PWM_CLK_CTL,0x80000000); //pwm_clk=mclk_in(32M)/(2*(0 +1))= 16M ; max output HZ 160KHZ
- __write_hw_reg32(CPR_PWM_CLK_CTL,0x80000001); //pwm_clk=mclk_in(32M)/(2*(1 +1))= 8M ; max output HZ 80KHZ
- __write_hw_reg32(CPR_PWM_CLK_CTL,0x80000003); //pwm_clk=mclk_in(32M)/(2*(3 +1))= 4M ; max output HZ 40KHZ
- __write_hw_reg32(CPR_PWM_CLK_CTL,0x80000007); //pwm_clk=mclk_in(32M)/(2*(7 +1))= 2M ; max output HZ 20KHZ
- __write_hw_reg32(CPR_PWM_CLK_CTL,0x80000009); //pwm_clk=mclk_in(32M)/(2*(9 +1))=1.6M ; max output HZ 16KHZ
- __write_hw_reg32(CPR_PWM_CLK_CTL,0x8000000F); //pwm_clk=mclk_in(32M)/(2*(15+1))= 1M ; max output HZ 10KHZ
- __write_hw_reg32(CPR_PWM_CLK_CTL,0x8000004F); //pwm_clk=mclk_in(32M)/(2*(79+1))=0.2M ; max output HZ 2KHZ
- */
- xc_set_pwm(ch,ocpy_ratio,period);
-
-
- }
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