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m05e00 done

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hugogogo
2025-03-13 18:42:34 +01:00
parent 7ca02352d9
commit 00bcdb1a79
4 changed files with 18 additions and 15 deletions
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0
module05/ex00/adc.h → headers/adc.h
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18
module05/ex00/adc.c
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@@ -10,18 +10,16 @@
// - disabling the Power Reduction ADC bit, PRADC
// - writing a logical one to the ADC Start Conversion bit, ADSC
#define ADC_PRESCALER 8
void adc_init() {
ADMUX = (1 << REFS0); // Table 24-3 : set voltage reference, AVCC with external capacitor at AREF pin
ADCSRA = (1 << ADEN) // 24.9.2 : enable ADC
| ADC_PRESCALE_SET(ADC_PRESCALER); // Table 24-5 : prescaler ADC
void adc_init(uint8_t prescaler_value) {
ADMUX = (1 << REFS0); // Table 24-3 : set voltage reference, AVCC with external capacitor at AREF pin
ADCSRA = (1 << ADEN); // 24.9.2 : enable ADC
ADCSRA |= ADC_PRESCALE_SET(prescaler_value); // Table 24-5 : prescaler ADC
}
uint16_t adc_read(uint8_t channel) {
CLEAR(PRR, PRADC); // 24.3 : ensure power reduction is disabled for ADC, (10.11.3 : PRR – Power Reduction Register)
ADMUX = (ADMUX & 0xF0) | (channel & 0x0F); // Select ADC channel
ADCSRA |= (1 << ADSC); // 24.9.2 : Start conversion, ADSC: ADC Start Conversion
while (ADCSRA & (1 << ADSC)); // Wait for completion
CLEAR(PRR, PRADC); // 24.3 : ensure power reduction is disabled for ADC, (10.11.3 : PRR – Power Reduction Register)
ADMUX = (ADMUX & 0b11110000) | (channel & 0b1111); // Table 24-4 : Select ADC channel, (Table 14-6 : alternate function for RV1 on PC0 -> ADC0)
ADCSRA |= (1 << ADSC); // 24.9.2 : Start conversion, ADSC: ADC Start Conversion
while (ADCSRA & (1 << ADSC)); // Wait for completion
return ADC;
}

4
module05/ex00/header.h
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@@ -18,13 +18,13 @@
// main.c
void int_to_hex_string(uint64_t value, char *out, uint8_t num_digits);
// adc.c
void adc_init();
void adc_init(uint8_t prescaler_value);
uint16_t adc_read(uint8_t channel);
// uart.c
void uart_init();
void uart_tx(char c);
void uart_printstr(const char* str);
void uart_printstr_endl(const char* str)
void uart_printstr_endl(const char* str);
//
// MACROS

11
module05/ex00/main.c
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@@ -1,6 +1,11 @@
#include "header.h"
void int_to_hex_string(uint64_t value, char *out, uint8_t num_digits) {
// 1.1.7 : AVCC is the supply voltage pin for the A/D Converter, PC3:0, and ADC7:6
// 1.1.8 : AREF is the analog reference pin for the A/D Converter
#define ADC_PRESCALER 8
void int_to_hex_string(uint64_t value, char *out, uint8_t num_digits) { // num_digits : number of digit of the output, ex 2 for 3FF (1023) -> FF
for (uint8_t i = 0; i < num_digits; ++i) {
uint8_t shift = (num_digits - 1 - i) * 4;
out[i] = INT_TO_HEX_CHAR((value >> shift) & 0x0F);
@@ -10,10 +15,10 @@ void int_to_hex_string(uint64_t value, char *out, uint8_t num_digits) {
// description
int main() {
const char buffer[4];
char buffer[4];
SREG |= ENABLE_GLOBAL_INTERRUPT; // 7.3.1 : Status Register, bit 7 : I – Global Interrupt Enable
uart_init();
adc_init();
adc_init(ADC_PRESCALER);
while(1) {
uint16_t value = adc_read(0); // Read from ADC0 (A0)