Working countdown

.gitignore

@@ -0,0 +1 @@
+bin

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "lib/usart"]
+	path = lib/usart
+	url = git@git.technical.kiwi:avr/usart.git

makefile

@@ -7,13 +7,14 @@ OBJCOPY=avr-objcopy
 CFLAGS=-Wall -g -O -mmcu=${MCU} -DF_CPU=${F_CPU} -I. -std=gnu++11 
 
 SRC=$(wildcard src/*.cpp)
+LIB=$(wildcard lib/*/src/*.cpp)
 
 default: clean build flash
 
 build:
 	mkdir -p bin
-	${CC} ${CFLAGS} -o bin/main.bin  ${SRC}  -w
-	${CC} ${CFLAGS} -o bin/main.elf ${SRC} -w
+	${CC} ${CFLAGS} -o bin/main.bin  ${SRC} ${LIB} -w
+	${CC} ${CFLAGS} -o bin/main.elf ${SRC} ${LIB} -w
 	${OBJCOPY} -j .text -j .data -O ihex bin/main.bin bin/main.hex
 
 flash:

src/main.cpp

@@ -1,12 +1,10 @@
 #include <avr/io.h>
 #include <avr/interrupt.h>
-#include <stdio.h>
+#include <util/delay.h>
+#include "../lib/usart/src/usart.h"
 
 #define F_CPU 8000000UL // CPU Clock Frequency in Hz
 
-#define BAUD_RATE 9600
-#define BAUD_RATE_DIVISOR ((F_CPU / (16UL * BAUD_RATE)) - 1)
-
 // Define segments for each digit
 #define A (1<<PB5)
 #define B (1<<PB7)
@@ -17,8 +15,6 @@
 #define G (1<<PB0)
 #define DP (1<<PB2)
 
-
-
 // Segment patterns for digits 0 to 9
 const uint8_t numbers[] = {
     (A | B | C | D | E | F),   // 0
@@ -33,19 +29,19 @@ const uint8_t numbers[] = {
     (A | B | C | F | G)        // 9
 };
 
+bool decimalpoint[6] = {true, false, true, false, true, false}; // Decimal points for each digit
+
 // Array to store digits to be displayed
-volatile uint8_t digits[] = {0, 0, 0, 0, 0, 0};
-
-// Current digit index
-volatile uint8_t currentDigit = 0;
-
-// Function to display a single digit
-void displayDigit(uint8_t digit) {
-    PORTB = numbers[digit];
-}
+volatile uint8_t digits[] = {0, 5, 9, 5, 9, 9}; // Initial countdown value: 59:59.9
 
 // Function to turn on a specific digit
 void turnOnDigit(uint8_t digit) {
+    if (decimalpoint[digit]) {
+        PORTB |= DP;
+    } else {
+        PORTB &= ~DP;
+    }
+
     switch (digit) {
         case 0:
             PORTA |= (1<<PA1);
@@ -70,54 +66,54 @@ void turnOnDigit(uint8_t digit) {
     }
 }
 
-// Function to turn off all digits
-void turnOffAllDigits() {
-    PORTA &= ~((1<<PA1) | (1<<PA0));
-    PORTD &= ~((1<<PD2) | (1<<PD3) | (1<<PD4) | (1<<PD5));
-}
-
 // Timer/Counter1 Compare Match A interrupt
 ISR(TIMER1_COMPA_vect) {
-    turnOffAllDigits(); // Turn off all digits
-    displayDigit(digits[currentDigit]); // Display the current digit
+    static uint8_t currentDigit = 0;
+    PORTA &= ~((1<<PA1) | (1<<PA0));
+    PORTD &= ~((1<<PD2) | (1<<PD3) | (1<<PD4) | (1<<PD5));
+    PORTB = numbers[digits[currentDigit]];
     turnOnDigit(currentDigit); // Turn on the corresponding digit
     currentDigit = (currentDigit + 1) % 6; // Move to the next digit
 }
 
-// USART RX Complete interrupt
-ISR(USART_RXC_vect) {
-    static uint8_t d = 0;
-    uint8_t data = UDR; // Read the received data
-
-    if(data == 'X') {
-        d = 0; // Reset currentDigit to start receiving digits
-    } else if (data >= 0 && data <= 9 && currentDigit < 6) {
-        digits[d] = data;
-        d++;
+void updateDigits() {
+    if (digits[5] == 0) { // If milliseconds digit reaches 0
+        digits[5] = 9; // Reset milliseconds digit
+        if (digits[4] == 0) {
+            digits[4] = 9;
+            if (digits[3] == 0) {
+                digits[3] = 5;
+                if (digits[2] == 0) {
+                    digits[2] = 9;
+                    if (digits[1] == 0) {
+                        digits[1] = 5;
+                        if (digits[0] > 0) {
+                            digits[0]--;
+                        }
+                    } else {
+                        digits[1]--;
+                    }
+                } else {
+                    digits[2]--;
+                }
+            } else {
+                digits[3]--;
+            }
+        } else {
+            digits[4]--;
+        }
+    } else {
+        digits[5]--;
     }
-    // Echo back the received data
-    while (!(UCSRA & (1 << UDRE))); // Wait for the transmit buffer to be empty
-    UDR = data; // Send the received data back
 }
 
-int uart_putchar(char c, FILE *stream) {
-    if (c == '\n') {
-        uart_putchar('\r', stream);
-    }
-    // Wait for empty transmit buffer
-    while (!(UCSRA & (1 << UDRE)));
-    // Put data into buffer, sends the data
-    UDR = c;
-    return 0;
-}
-
-
 int main() {
     // Set PORTB as output for segments
     DDRB = 0xFF;
     // Set PORTA and PORTD as output for digit control
     DDRA |= (1<<PA0) | (1<<PA1);
     DDRD |= (1<<PD2) | (1<<PD3) | (1<<PD4) | (1<<PD5);
+    DDRD &= ~(1<<PD6);
 
     // Initialize Timer/Counter1 in CTC mode
     TCCR1B |= (1 << WGM12);
@@ -128,23 +124,25 @@ int main() {
     // Enable Timer/Counter1 Compare Match A interrupt
     TIMSK |= (1 << OCIE1A);
 
-    // Initialize USART
-    // Set baud rate to 9600
-    UBRRH = (BAUD_RATE_DIVISOR >> 8);
-    UBRRL = BAUD_RATE_DIVISOR;
-    // Enable receiver and RX complete interrupt
-    UCSRB |= (1<<TXEN) | (1 << RXEN) | (1 << RXCIE);
-    // Set frame format: 8 data bits, 1 stop bit
-    UCSRC = (1 << UCSZ1) | (1 << UCSZ0);
+    usart::init(9600); // Initialize USART with baud rate 9600
+
     // Enable global interrupts
     sei();
 
-    
-    static FILE mystdout;
-    fdev_setup_stream(&mystdout, uart_putchar, NULL, _FDEV_SETUP_WRITE);
-    stdout = &mystdout;
-    printf("Started");
+    bool pd6_high = false; // Track the state of PD6
+    usart::printf("Started");
     while (1) {
+        if (PIND & (1<<PD6)) {
+            if (!pd6_high) { // If PD6 was previously low
+                //usart::printf("PD6");
+                updateDigits(); // Update digits every time PD6 goes high
+                pd6_high = true; // Set the state to high
+            }
+        } else {
+            pd6_high = false; // Reset the state to low when PD6 is low
+        }
+
+        //_delay_us(10); // Add a delay to avoid rapid checking
     }
 
     return 0;