From 7cad1f67761cda3d4e7f5c6959d1f7af3bc106f3 Mon Sep 17 00:00:00 2001 From: hugogogo Date: Thu, 13 Mar 2025 18:47:24 +0100 Subject: [PATCH] init m05e01 --- module05/ex01/Makefile | 1 + module05/ex01/adc.c | 25 ++++++++++++++ module05/ex01/header.h | 33 ++++++++++++++++++ module05/ex01/main.c | 32 ++++++++++++++++++ module05/ex01/uart.c | 77 ++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 168 insertions(+) create mode 100644 module05/ex01/Makefile create mode 100644 module05/ex01/adc.c create mode 100644 module05/ex01/header.h create mode 100644 module05/ex01/main.c create mode 100644 module05/ex01/uart.c diff --git a/module05/ex01/Makefile b/module05/ex01/Makefile new file mode 100644 index 0000000..2e40cba --- /dev/null +++ b/module05/ex01/Makefile @@ -0,0 +1 @@ +include ../../Makefile \ No newline at end of file diff --git a/module05/ex01/adc.c b/module05/ex01/adc.c new file mode 100644 index 0000000..4e0e062 --- /dev/null +++ b/module05/ex01/adc.c @@ -0,0 +1,25 @@ +#include "header.h" + +// Table 14-6. Port C Pins Alternate Functions +// - PC0 -> ADC0 (ADC Input Channel 0) +// -> PCINT8 (Pin Change Interrupt 8) +// +// 24.2 : The ADC generates a 10-bit result which is presented in the ADC Data Registers, ADCH and ADCL +// +// START A CONVERSTION in single conversion mode : +// - disabling the Power Reduction ADC bit, PRADC +// - writing a logical one to the ADC Start Conversion bit, ADSC + +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 & 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; +} diff --git a/module05/ex01/header.h b/module05/ex01/header.h new file mode 100644 index 0000000..6b7ea32 --- /dev/null +++ b/module05/ex01/header.h @@ -0,0 +1,33 @@ +#ifndef HEADER_H +#define HEADER_H + +#include +#include +#include + +#include "utils.h" +#include "bitmanip.h" +#include "interrupt.h" +#include "timer.h" +#include "usart.h" +#include "adc.h" + +// +// PROTOTYPES +// +// main.c +void int_to_hex_string(uint64_t value, char *out, uint8_t num_digits); +// adc.c +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); + +// +// MACROS +// + +#endif // HEADER_H \ No newline at end of file diff --git a/module05/ex01/main.c b/module05/ex01/main.c new file mode 100644 index 0000000..b885c02 --- /dev/null +++ b/module05/ex01/main.c @@ -0,0 +1,32 @@ +#include "header.h" + +// 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); + } + out[num_digits] = '\0'; +} + +// description +int main() { + char buffer[4]; + 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 + } +} + +// ISR(ADC_vect) { // Table 12-6 : interrupt vector for ADC Conversion Complete +// } \ No newline at end of file diff --git a/module05/ex01/uart.c b/module05/ex01/uart.c new file mode 100644 index 0000000..f0231f0 --- /dev/null +++ b/module05/ex01/uart.c @@ -0,0 +1,77 @@ +#include "header.h" + +// MACROS +// USART +#define USART_BAUDRATE 115200 +#define INPUT_SIZE 7 + +// GLOBAL VARIABLES + +// +// FUNCTIONS +// +void uart_init() { + UBRR0H = (unsigned char) (BAUD_PRESCALER(USART_BAUDRATE) >> 8); // 20.11.5 : UBRRnL and UBRRnH – USART Baud Rate Registers + UBRR0L = (unsigned char) BAUD_PRESCALER(USART_BAUDRATE); + UCSR0C = DATA_EIGHT_BIT; // 20.11.4 : set Frame Format + UCSR0B = TRANSMITTER_ENABLED; // 20.11.3 : enable Receiver, Transmitter, and interrupts +} + +// char uart_rx(void) { +// while (!TEST(UCSR0A, RXC0)); // 20.11.2 : do nothing until there are unread data in the receive buffer (UDRn), (RXCn flag in UCSRnA register set to 1 when buffer has data) +// return UDR0; // 20.11.1 : get data in buffer, UDRn – USART I/O Data Register (read and write) +// } + +void uart_tx(char c) { + while (!TEST(UCSR0A, UDRE0)); // 20.11.2 : do nothing until UDRn buffer is empty, (UDREn flag in UCSRnA register set to 1 when buffer empty) + UDR0 = (unsigned char) c; // 20.11.1 : Put data into buffer, UDRn – USART I/O Data Register (read and write) +} + +void uart_printstr(const char* str) { + while (*str) { + uart_tx(*str); + str++; + } +} + +void uart_printstr_endl(const char* str) { + uart_printstr(str); + uart_printstr("\r\n"); +} + +// ISR(USART_RX_vect) { // Table 12-6 : we select the code for USART Receive +// char received_char = UDR0; // read received character +// if (received_char == '\b' || received_char == 127) { // if backspace is received +// if (input_index <= 0) { +// return; +// } +// if (input_index >= INPUT_SIZE) { +// return; +// } +// remove_last_character(); +// input_index--; +// uart_tx('\b'); // Move cursor back +// uart_tx(' '); // Erase the character on screen +// uart_tx('\b'); // Move cursor back again +// } else if (received_char == '\n' || received_char == '\r') { // if enter is received +// if (input_index != INPUT_SIZE) { +// return; +// } +// set_color((char *)color_input); +// reset_input(); +// } else { // any other character +// if (input_index >= INPUT_SIZE) { +// return; +// } +// if (!is_valid_color_input(received_char)) { +// return; +// } +// fill_str(received_char); +// uart_tx(received_char); +// input_index++; +// } +// } + +// ISR(USART_TX_vect) { // Table 12-6 : we select the code for USART Transmit +// char received_char = UDR0; // read received character +// }