44 lines
1.6 KiB
C
44 lines
1.6 KiB
C
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#include <reg_stm32f4xx.h>
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#include <stdint.h>
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void adc_init(void)
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{
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// Clock configuration
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RCC->APB2ENR |= 0x00000400;
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RCC->APB1ENR |= 0x00000020;
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// Analog pin configuration
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GPIOF->MODER |= 0x00003000;
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// ADC configuration
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ADC3->CR1 |= 0x02000000; // Resolution
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// -> 8 Bit,
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// scan mode
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// -> disabled
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ADC3->CR2 |= 0x00000002; // Continous
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// conversion
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// mode ->
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// enabled
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// Enable ADC conversion
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ADC3->CR2 |= 0x00000001; // ADC3 enable
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// Select the channel to be read from
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ADC3->SMPR2 |= 0x00006000; // Channel 4 sampling
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// time -> 144 cycles
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ADC3->SQR3 |= 0x00000004; // Channel 4 rank
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// -> 1 (?)
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}
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uint8_t adc_get_value(void)
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{
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// Start the conversion
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ADC3->CR2 |= 0x40000000;
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// Wait till conversion is finished
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while (!ADC3->SR & 0x00000002) ;
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// Return the converted data
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return (uint8_t)ADC3->DR & 0x000000ff;
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}
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