kopia lustrzana https://github.com/mikaelnousiainen/RS41ng
67 wiersze
1.9 KiB
C
67 wiersze
1.9 KiB
C
#include <stm32f10x_rcc.h>
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#include <stm32f10x_tim.h>
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#include <misc.h>
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#include "datatimer.h"
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void (*system_handle_data_timer_tick)() = NULL;
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void data_timer_init(uint32_t baud_rate)
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{
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// Timer frequency = TIM_CLK/(TIM_PSC+1)/(TIM_ARR + 1)
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// TIM_CLK =
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// TIM_PSC = Prescaler
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// TIM_ARR = Period
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TIM_DeInit(TIM2);
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TIM_TimeBaseInitTypeDef tim_init;
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RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
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RCC_APB2PeriphResetCmd(RCC_APB1Periph_TIM2, DISABLE);
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// The data timer assumes a 24 MHz clock source
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tim_init.TIM_Prescaler = 24 - 1; // tick every 1/1000000 s
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tim_init.TIM_CounterMode = TIM_CounterMode_Up;
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tim_init.TIM_Period = (uint16_t) ((1000000 / baud_rate) - 1);
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tim_init.TIM_ClockDivision = TIM_CKD_DIV1;
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tim_init.TIM_RepetitionCounter = 0;
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TIM_TimeBaseInit(TIM2, &tim_init);
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// No interrupts necessary for data timer, as it is only used for triggering DMA transfers
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TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
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TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
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NVIC_InitTypeDef nvic_init;
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nvic_init.NVIC_IRQChannel = TIM2_IRQn;
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nvic_init.NVIC_IRQChannelPreemptionPriority = 2;
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nvic_init.NVIC_IRQChannelSubPriority = 2;
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nvic_init.NVIC_IRQChannelCmd = ENABLE;
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NVIC_Init(&nvic_init);
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TIM_Cmd(TIM2, ENABLE);
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}
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void data_timer_uninit()
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{
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TIM_Cmd(TIM2, DISABLE);
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NVIC_InitTypeDef nvic_init;
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nvic_init.NVIC_IRQChannel = TIM2_IRQn;
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nvic_init.NVIC_IRQChannelPreemptionPriority = 2;
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nvic_init.NVIC_IRQChannelSubPriority = 2;
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nvic_init.NVIC_IRQChannelCmd = DISABLE;
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NVIC_Init(&nvic_init);
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TIM_ITConfig(TIM2, TIM_IT_Update, DISABLE);
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TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
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}
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void TIM2_IRQHandler(void)
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{
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if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET) {
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TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
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system_handle_data_timer_tick();
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}
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}
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