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#include "gd32f30x.h"
#include <stdio.h>
#include "gd32f307c_eval.h"
#define TIMER0_CH0CV ((uint32_t)0x40012C34)
void gpio_config(void);
void timer_config(void);
void dma_config(void);
/*!
\brief configure the GPIO ports
\param[in] none
\param[out] none
\retval none
*/
void gpio_config(void)
{
rcu_periph_clock_enable(RCU_GPIOA);
rcu_periph_clock_enable(RCU_AF);
/*configure PA8(TIMER0 CH0) as alternate function*/
gpio_init(GPIOA,GPIO_MODE_AF_PP,GPIO_OSPEED_50MHZ,GPIO_PIN_8);
}
void dma_config(void)
{
dma_parameter_struct dma_init_struct;
/* enable DMA clock */
rcu_periph_clock_enable(RCU_DMA0);
/* initialize DMA channel5 */
dma_deinit(DMA0,DMA_CH4);
/* DMA channel5 initialize */
dma_init_struct.periph_addr = (uint32_t)TIMER0_CH0CV;
dma_init_struct.periph_inc = DMA_PERIPH_INCREASE_DISABLE;
dma_init_struct.memory_addr = (uint32_t)buffer;
dma_init_struct.memory_inc = DMA_MEMORY_INCREASE_ENABLE;
dma_init_struct.periph_width = DMA_PERIPHERAL_WIDTH_16BIT;
dma_init_struct.memory_width = DMA_MEMORY_WIDTH_16BIT;
dma_init_struct.direction = DMA_MEMORY_TO_PERIPHERAL;
dma_init_struct.number = 3;
dma_init_struct.priority = DMA_PRIORITY_ULTRA_HIGH;
dma_init(DMA0,DMA_CH4,&dma_init_struct);
dma_circulation_enable(DMA0,DMA_CH4);
/* enable DMA channel5 */
dma_channel_enable(DMA0,DMA_CH4);
}
void timer_config(void)
{
/* TIMER0 DMA Transfer example -------------------------------------------------
TIMER0CLK = 120MHz, Prescaler = 119
TIMER0 counter clock = systemcoreclock/120 = 1MHz.
the objective is to configure TIMER0 channel 1 to generate PWM
signal with a frequency equal to 1KHz and a variable duty cycle(25%,50%,75%) that is
changed by the DMA after a specific number of update DMA request.
the number of this repetitive requests is defined by the TIMER0 repetition counter,
each 2 update requests, the TIMER0 Channel 0 duty cycle changes to the next new
value defined by the buffer .
-----------------------------------------------------------------------------*/
timer_oc_parameter_struct timer_ocintpara;
timer_parameter_struct timer_initpara;
rcu_periph_clock_enable(RCU_TIMER0);
timer_deinit(TIMER0);
/* TIMER0 configuration */
timer_initpara.prescaler = 119;
timer_initpara.alignedmode = TIMER_COUNTER_EDGE;
timer_initpara.counterdirection = TIMER_COUNTER_UP;
timer_initpara.period = 999;
timer_initpara.clockdivision = TIMER_CKDIV_DIV1;
timer_initpara.repetitioncounter = 1;
timer_init(TIMER0,&timer_initpara);
/* CH0 configuration in PWM1 mode */
timer_ocintpara.outputstate = TIMER_CCX_ENABLE;
timer_ocintpara.outputnstate = TIMER_CCXN_DISABLE;
timer_ocintpara.ocpolarity = TIMER_OC_POLARITY_HIGH;
timer_ocintpara.ocnpolarity = TIMER_OCN_POLARITY_HIGH;
timer_ocintpara.ocidlestate = TIMER_OC_IDLE_STATE_HIGH;
timer_ocintpara.ocnidlestate = TIMER_OCN_IDLE_STATE_LOW;
timer_channel_output_config(TIMER0,TIMER_CH_0,&timer_ocintpara);
timer_channel_output_pulse_value_config(TIMER0,TIMER_CH_0,buffer[0]);
timer_channel_output_mode_config(TIMER0,TIMER_CH_0,TIMER_OC_MODE_PWM0);
timer_channel_output_shadow_config(TIMER0,TIMER_CH_0,TIMER_OC_SHADOW_DISABLE);
/* TIMER0 primary output enable */
timer_primary_output_config(TIMER0,ENABLE);
/* TIMER0 update DMA request enable */
timer_dma_enable(TIMER0,TIMER_DMA_UPD);
/* auto-reload preload enable */
timer_auto_reload_shadow_enable(TIMER0);
/* TIMER0 counter enable */
timer_enable(TIMER0);
}
int main(void)
{
gpio_config();
dma_config();
timer_config();
while (1);
}
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