first version m05e00

module05/ex00/header.h

@@ -15,6 +15,10 @@
 // PROTOTYPES
 //
 // main.c
+// uart.c
+void uart_init();
+void uart_tx(char c);
+void uart_printstr(const char* str);
 
 //
 // MACROS

module05/ex00/main.c

@@ -1,6 +1,56 @@
 #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
+
+#define INT_TO_HEX_CHAR(n) ((n) < 10 ? ('0' + (n)) : ('A' + ((n) - 10)))
+void int_to_hex_string(uint64_t value, char *out, uint8_t num_digits) {
+    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';
+}
+void word_to_hex(uint16_t value, char *out) {
+    out[0] = INT_TO_HEX_CHAR((value >> 8) & 0x0F);
+    out[1] = INT_TO_HEX_CHAR((value >> 4) & 0x0F);
+    out[2] = INT_TO_HEX_CHAR(value & 0x0F);
+    out[3] = '\0';
+}
+
+void adc_init() {
+    ADMUX = (1 << REFS0); // AVcc reference, ADC0
+    ADCSRA = (1 << ADEN)  // Enable ADC
+           | (1 << ADPS2) | (1 << ADPS1) | (1 << ADPS0); // Prescaler = 128
+}
+
+uint16_t adc_read(uint8_t channel) {
+    ADMUX = (ADMUX & 0xF0) | (channel & 0x0F);  // Select ADC channel
+    ADCSRA |= (1 << ADSC);                     // Start conversion
+    while (ADCSRA & (1 << ADSC));              // Wait for completion
+    return ADC;
+}
+
 // description
 int main() {
-	while(1);
+    char buffer[4];
+	SREG |= ENABLE_GLOBAL_INTERRUPT;												// 7.3.1 : Status Register, bit 7 : I – Global Interrupt Enable
+	uart_init();
+
+	adc_init();
+
+	while(1) {
+        uint16_t value = adc_read(0); // Read from ADC0 (A0)
+        // snprintf(buffer, sizeof(buffer), "ADC: %u\r\n", value);
+		word_to_hex(value, buffer);
+        uart_printstr(buffer);
+        uart_printstr("\r\n");
+        _delay_ms(20); // Wait 20ms
+	}
 }
+
+// ISR(ADC_vect) {		// Table 12-6 : interrupt vector for ADC Conversion Complete
+// }

module05/ex00/uart.c

@@ -0,0 +1,72 @@
+#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++;
+	}
+}
+
+// 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
+// }