求解！GD32E103输出PWM，占空比小的时候有空白信号

只看该作者 · 2022-3-2 16:20

{

rcu_periph_clock_enable(RCU_GPIOA);
rcu_periph_clock_enable(RCU_AF);

gpio_init(GPIOA, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_0);
gpio_init(GPIOA, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_1);
gpio_init(GPIOA, GPIO_MODE_AF_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_3);

timer_oc_parameter_struct timer_ocinitpara;
timer_parameter_struct timer_initpara;

rcu_periph_clock_enable(RCU_TIMER1);

timer_deinit(TIMER1);
/* initialize TIMER init parameter struct */
timer_struct_para_init(&timer_initpara);
/* TIMER1 configuration */
timer_initpara.prescaler       = 6;
timer_initpara.alignedmode    = TIMER_COUNTER_EDGE;
timer_initpara.counterdirection  = TIMER_COUNTER_UP;
timer_initpara.period          = 3999;
timer_initpara.clockdivision    = TIMER_CKDIV_DIV1;
timer_initpara.repetitioncounter = 0;
timer_init(TIMER1, &timer_initpara);

/* initialize TIMER channel output parameter struct */
timer_channel_output_struct_para_init(&timer_ocinitpara);
/* CH0, CH1 and CH3 configuration in PWM mode */
timer_ocinitpara.outputstate  = TIMER_CCX_ENABLE;
timer_ocinitpara.outputnstate = TIMER_CCXN_DISABLE;
timer_ocinitpara.ocpolarity = TIMER_OC_POLARITY_HIGH;
timer_ocinitpara.ocnpolarity  = TIMER_OCN_POLARITY_HIGH;
timer_ocinitpara.ocidlestate  = TIMER_OC_IDLE_STATE_LOW;
timer_ocinitpara.ocnidlestate = TIMER_OCN_IDLE_STATE_LOW;

timer_channel_output_config(TIMER1, TIMER_CH_0, &timer_ocinitpara);
timer_channel_output_config(TIMER1, TIMER_CH_1, &timer_ocinitpara);
timer_channel_output_config(TIMER1, TIMER_CH_3, &timer_ocinitpara);

/* CH0 configuration in PWM mode0, duty cycle 25% */
timer_channel_output_pulse_value_config(TIMER1, TIMER_CH_0, 400);
timer_channel_output_mode_config(TIMER1, TIMER_CH_0, TIMER_OC_MODE_PWM0);
timer_channel_output_shadow_config(TIMER1, TIMER_CH_0, TIMER_OC_SHADOW_DISABLE);

timer_channel_output_pulse_value_config(TIMER1, TIMER_CH_1, 0);
timer_channel_output_mode_config(TIMER1, TIMER_CH_1, TIMER_OC_MODE_PWM0);
timer_channel_output_shadow_config(TIMER1, TIMER_CH_1, TIMER_OC_SHADOW_DISABLE);

timer_channel_output_pulse_value_config(TIMER1, TIMER_CH_3, 0);
timer_channel_output_mode_config(TIMER1, TIMER_CH_3, TIMER_OC_MODE_PWM0);
timer_channel_output_shadow_config(TIMER1, TIMER_CH_3, TIMER_OC_SHADOW_DISABLE);

/* auto-reload preload enable */
timer_auto_reload_shadow_enable(TIMER1);
/* auto-reload preload enable */
timer_enable(TIMER1);
}

void CH1_PWMSet(uint16_t value)
{
timer_channel_output_pulse_value_config(TIMER1, TIMER_CH_0, value);
}

通用timer1的通道0、1、3输出PWM，当占空比的值偏小，大概小于600左右时，PWM输出是一段一段的，不连续。
占空比设置变高以后正常。

求解。