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m05e01 done

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hugogogo
2025-03-15 13:17:46 +01:00
parent 2fd1d7d931
commit 5904f7c5e0
4 changed files with 67 additions and 36 deletions
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35
module05/ex01/main.c
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@@ -2,31 +2,28 @@
// 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
// 24.4 : frequency needs to be between 50kHz and 200kHz, for less than 10bits accuracy it can be >200kHz
// -> Frequence_ADC = Frequance_CPU / Prescaler (Fadc = Fcpu/P):
// - P = 2 -> Fadc = 16,000,000 / 2 = 8,000,000 = 8MHz
// - P = 4 -> Fadc = 16,000,000 / 4 = 4,000,000 = 4MHz
// - P = 8 -> Fadc = 16,000,000 / 8 = 2,000,000 = 2MHz
// - P = 16 -> Fadc = 16,000,000 / 16 = 1,000,000 = 1MHz
// - P = 32 -> Fadc = 16,000,000 / 32 = 500,000 = 500KHz
// - P = 64 -> Fadc = 16,000,000 / 64 = 250,000 = 250KHz -> OK
// - P = 128 -> Fadc = 16,000,000 / 128 = 125,000 = 125KHz -> OK
#define ADC_PRESCALER 8
#define ADC_PRESCALER 64 // Table 24-5 : can only be 2, 4, 8, 16, 32, 64, or 128
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);
}
out[num_digits] = '\0';
}
volatile uint8_t adc_channel = 0; // Table 14-6 : alternate function for RV1 on PC0 -> ADC0, LDR on PC1 -> ADC1, NTC on PC2 -> ADC2 ...
// description
// read 3 analog values and print them in uart as hexadecimal 2-number : potentiometer RV1 (Variable Resistor), photoresistor LDR (Light Dependent Resistor), thermistor NTC (Negative Temperature Coefficient)
int main() {
char buffer[4];
SREG |= ENABLE_GLOBAL_INTERRUPT; // 7.3.1 : Status Register, bit 7 : I – Global Interrupt Enable
SREG |= ENABLE_GLOBAL_INTERRUPT; // 7.3.1 : Status Register, bit 7 : I – Global Interrupt Enable
uart_init();
adc_init(ADC_PRESCALER);
while(1) {
uint16_t value = adc_read(0); // Read from ADC0 (A0)
int_to_hex_string(value, buffer, 3);
uart_printstr_endl(buffer);
_delay_ms(20); // Wait 20ms
}
}
timer_1B_init();
// ISR(ADC_vect) { // Table 12-6 : interrupt vector for ADC Conversion Complete
// }
while(1);
}