works but color is wrong

module03/ex03/uart.c

@@ -0,0 +1,121 @@
+#include "header.h"
+
+// MACROS
+// USART
+#define USART_BAUDRATE		115200
+#define INPUT_SIZE			7
+
+// GLOBAL VARIABLES
+volatile char color_input[INPUT_SIZE + 1] = {0};
+volatile int input_index = 0;
+
+//
+// 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 |= ASYNCHRONOUS | PARITY_DISABLED | STOP_ONE_BIT | DATA_EIGHT_BIT;		// 20.11.4 : set Frame Format
+	UCSR0B |= RECEIVER_ENABLED | TRANSMITTER_ENABLED | INTERRUPT_RECEIVER_ENABLED;	// 20.11.3 : enable Receiver and Transmitter, and interrupt on receiver
+	SREG |= ENABLE_GLOBAL_INTERRUPT;												// 7.3.1 : Status Register, bit 7 : I – Global Interrupt Enable
+}
+
+char uart_rx(void) {
+	while (TEST(UCSR0A, RXC0) == 0);												// 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) == 0);												// 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 12-7 : 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++;
+	}
+}
+
+int is_valid_color_input(char c) {
+	if (input_index == 0) {
+		if (c == '#') {
+			return TRUE;
+		} else {
+			return FALSE;
+		}
+	}
+	if (input_index >= INPUT_SIZE) {
+		return FALSE;
+	}
+	if (c >= '0' && c <= '9') {
+		return TRUE;
+	} else if (c >= 'A' && c <= 'F') {
+		return TRUE;
+	} else if (c >= 'a' && c <= 'f') {
+		return TRUE;
+	}
+	return FALSE;
+}
+
+void fill_str(char input) {
+	if (input_index >= INPUT_SIZE) {
+		return;
+	}
+	color_input[input_index] = input;
+}
+
+void remove_last_character() {
+	color_input[input_index] = 0;
+}
+
+int strlength(volatile char *str) {
+	int length = 0;
+	while (*str) {
+		length++;
+		str++;
+	}
+	return length;
+}
+
+void reset_input() {
+	for(int i = 0; i < INPUT_SIZE; i++) {
+		color_input[i] = 0;
+	}
+	uart_tx('\r');
+	uart_tx('\n');
+	input_index = 0;
+}