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feat(ex03): done !

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Maix0 2026-04-16 17:29:49 +02:00
parent a777f9ac5e
commit 6df43256c6
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55
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# Makefile
MCU=atmega328p
F_CPU=16000000
CC=avr-gcc
OBJCOPY=avr-objcopy
CFLAGS=-std=c99 -Wall -Wextra -g -Os -mmcu=$(MCU) -DF_CPU=$(F_CPU) -Iinclude
IFLAGS=
TARGET=main
SERIAL=-P /dev/ttyUSB0 -b 115200
SRC_DIR=src
OBJ_DIR=build
SRC_FILES=main.c utils.c uart.c
OBJ_FILES=$(patsubst %.c,%.o,$(SRC_FILES))
SRC=$(addprefix $(SRC_DIR)/,$(SRC_FILES))
OBJ=$(addprefix $(OBJ_DIR)/,$(OBJ_FILES))
ELF_FILE=$(OBJ_DIR)/$(TARGET).elf
HEX_FILE=$(OBJ_DIR)/$(TARGET).hex
all: flash
re: fclean all
fclean: clean
rm -f $(HEX_FILE)
rm -f $(ELF_FILE)
clean:
rm -rf $(OBJ_DIR)
hex: $(HEX_FILE)
flash: hex
avrdude -p $(MCU) -c arduino -U flash:w:$(HEX_FILE):i $(SERIAL)
$(OBJ_DIR)/%.o: $(SRC_DIR)/%.c
@mkdir -p $(shell dirname $@)
$(CC) $(CFLAGS) $(IFLAGS) -c $< -o $@
$(ELF_FILE): $(OBJ)
$(CC) $(CFLAGS) $(OBJ) -o $@
$(HEX_FILE): $(ELF_FILE)
$(OBJCOPY) -j .text -j .data -O ihex $< $@
print:
@echo $(SRC)
@echo $(OBJ)
@echo $(ELF_FILE)
@echo $(HEX_FILE)

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#ifndef MYSTDINT_H
#define MYSTDINT_H
typedef unsigned int uint16_t;
typedef signed int int16_t;
typedef unsigned char uint8_t;
typedef signed char int8_t;
typedef uint8_t bool;
#define true (1)
#define false (0)
#define NULL ((void*)0)
#endif /* MYSTDINT_H */

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ex03/include/timer0.h Normal file
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#ifndef TIMER0_H
# define TIMER0_H
# include <avr/io.h>
# include "mystd.h"
# include "timer_global.h"
static inline void t0_init_fpwm_3(e_timer_prescaler prescaler) {
// Fast PWM (8-bit): WGM22:0 = 0b011
TCCR0A = _BV(WGM00) | _BV(WGM01);
// reset to zero -> timer off
TCCR0B &= ~(_BV(CS02) | _BV(CS01) | _BV(CS00));
// set the correct prescaler
switch (prescaler) {
case (PRESCALER_1): {
TCCR0B |= (_BV(CS00));
break;
}
case (PRESCALER_8): {
TCCR0B |= (_BV(CS01));
break;
}
case (PRESCALER_64): {
TCCR0B |= (_BV(CS01) | _BV(CS00));
break;
}
case (PRESCALER_256): {
TCCR0B |= (_BV(CS02));
break;
}
case (PRESCALER_1024): {
TCCR0B |= (_BV(CS02) | _BV(CS00));
break;
}
case (PRESCALER_OFF): {
break;
}
}
}
static inline void t0_set_ocr(enum e_timer_output output, uint8_t value) {
if (output & TO_A)
OCR0A = value;
if (output & TO_B)
OCR0B = value;
}
static inline void t0_set_out_mode(enum e_timer_output output, enum e_timer_output_mode mode) {
if (output & TO_A) {
TCCR0A &= ~(_BV(COM0A1) | _BV(COM0A0));
switch (mode) {
case (TOM_00): {
break;
}
case (TOM_10): {
TCCR0A |= (_BV(COM0A1));
break;
}
case (TOM_01): {
TCCR0A |= (_BV(COM0A0));
break;
}
case (TOM_11): {
TCCR0A |= (_BV(COM0A1) | _BV(COM0A0));
break;
}
}
}
if (output & TO_B) {
TCCR0A &= ~(_BV(COM0B1) | _BV(COM0B0));
switch (mode) {
case (TOM_00): {
break;
}
case (TOM_10): {
TCCR0A |= (_BV(COM0B1));
break;
}
case (TOM_01): {
TCCR0A |= (_BV(COM0B0));
break;
}
case (TOM_11): {
TCCR0A |= (_BV(COM0B1) | _BV(COM0B0));
break;
}
}
}
}
// OC2B => RED => PD3
// OC0B => GREEN => PD5
// OC0A => BLUE => PD6
#endif /* TIMER0_H */
/*
// OC2B = PD3 → output
DDRD |= _BV(DDD3) | _BV(DDD5) | _BV(DDD6);
// Fast PWM (8-bit): WGM22:0 = 0b011
TCCR0A = _BV(WGM00) | _BV(WGM01);
TCCR0A |= _BV(COM0B1);
// 50% duty cycle
OCR0B = 128;
// Start timer, prescaler = 64
TCCR0B = _BV(CS02);
*/

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#ifndef TIMER2_H
# define TIMER2_H
# include <avr/io.h>
# include "mystd.h"
# include "timer_global.h"
static inline void t2_init_fpwm_3(e_timer_prescaler prescaler) {
// Fast PWM (8-bit): WGM22:0 = 0b011
TCCR2A = _BV(WGM20) | _BV(WGM21);
// reset to zero -> timer off
TCCR2B &= ~(_BV(CS22) | _BV(CS21) | _BV(CS20));
// set the correct prescaler
switch (prescaler) {
case (PRESCALER_1): {
TCCR2B |= (_BV(CS20));
break;
}
case (PRESCALER_8): {
TCCR2B |= (_BV(CS21));
break;
}
case (PRESCALER_64): {
TCCR2B |= (_BV(CS21) | _BV(CS20));
break;
}
case (PRESCALER_256): {
TCCR2B |= (_BV(CS22));
break;
}
case (PRESCALER_1024): {
TCCR2B |= (_BV(CS22) | _BV(CS20));
break;
}
case (PRESCALER_OFF): {
break;
}
}
}
static inline void t2_set_ocr(enum e_timer_output output, uint8_t value) {
if (output & TO_A)
OCR2A = value;
if (output & TO_B)
OCR2B = value;
}
static inline void t2_set_out_mode(enum e_timer_output output, enum e_timer_output_mode mode) {
if (output & TO_A) {
TCCR2A &= ~(_BV(COM2A1) | _BV(COM2A0));
switch (mode) {
case (TOM_00): {
break;
}
case (TOM_10): {
TCCR2A |= (_BV(COM2A1));
break;
}
case (TOM_01): {
TCCR2A |= (_BV(COM2A0));
break;
}
case (TOM_11): {
TCCR2A |= (_BV(COM2A1) | _BV(COM2A0));
break;
}
}
}
if (output & TO_B) {
TCCR2A &= ~(_BV(COM2B1) | _BV(COM2B0));
switch (mode) {
case (TOM_00): {
break;
}
case (TOM_10): {
TCCR2A |= (_BV(COM2B1));
break;
}
case (TOM_01): {
TCCR2A |= (_BV(COM2B0));
break;
}
case (TOM_11): {
TCCR2A |= (_BV(COM2B1) | _BV(COM2B0));
break;
}
}
}
}
// OC2B => RED => PD3
// OC0B => GREEN => PD5
// OC0A => BLUE => PD6
#endif /* TIMER0_H */
/*
// OC2B = PD3 → output
DDRD |= _BV(DDD3) | _BV(DDD5) | _BV(DDD6);
// Fast PWM (8-bit): WGM22:0 = 0b011
TCCR2A = _BV(GM20) | _BV(GM21);
TCCR2A |= _BV(COM2B1);
// 50% duty cycle
OCR0B = 128;
// Start timer, prescaler = 64
TCCR2B = _BV(CS22);
*/

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#ifndef TIMER_GLOBAL_H
#define TIMER_GLOBAL_H
typedef enum e_timer_prescaler {
PRESCALER_OFF = 0,
PRESCALER_1 = 1,
PRESCALER_8 = 8,
PRESCALER_64 = 64,
PRESCALER_256 = 256,
PRESCALER_1024 = 1024,
} e_timer_prescaler;
typedef enum e_timer_output {
TO_A = (1 << 0),
TO_B = (1 << 1),
} e_timer_output;
typedef enum e_timer_output_mode {
TOM_00,
TOM_01,
TOM_10,
TOM_11,
} e_timer_output_mode;
#endif /* TIMER_GLOBAL_H */

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#ifndef UART_H
#define UART_H
#include "mystd.h"
void uart_init(void);
void uart_tx(char data);
void uart_sendstring(const char* str);
void uart_send_u8(uint8_t val);
void uart_send_u16(uint16_t val);
void uart_send_u8_hex(uint8_t val);
void uart_send_u16_hex(uint16_t val);
char uart_rx(void);
#endif /* UART_H */

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#ifndef UTILS_H
#define UTILS_H
#include "mystd.h"
void delay_ms(uint16_t count);
void ft_bzero(void *data, uint16_t size);
uint8_t ft_stridx(const char* str, char chr);
#endif /* UTILS_H */

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#include <avr/io.h>
#include "mystd.h"
#include "timer_global.h"
#include "utils.h"
#include "timer0.h"
#include "timer2.h"
#include "uart.h"
#define D5_R PD5
#define D5_G PD6
#define D5_B PD3
#define RGB_MASK (_BV(D5_R) | _BV(D5_G) | _BV(D5_B))
/*
name R# G# B#
red ff 0 0
green 0 ff 0
blue 0 0 ff
yellow ff ff 0
cyan 0 ff ff
magenta ff 0 ff
white ff ff ff
*/
#define COL_RED (_BV(D5_R))
#define COL_GREEN (_BV(D5_G))
#define COL_BLUE (_BV(D5_B))
#define COL_YELLOW (_BV(D5_R) | _BV(D5_G))
#define COL_CYAN (_BV(D5_G) | _BV(D5_B))
#define COL_MAGENTA (_BV(D5_R) | _BV(D5_B))
#define COL_WHITE (_BV(D5_R) | _BV(D5_G) | _BV(D5_B))
// OC2B => BLUE => PD3 | 2
// OC0B => RED => PD5 | 0
// OC0A => GREEN => PD6 | 0
void set_rgb(uint8_t r, uint8_t g, uint8_t b) {
if (r == 0x00) {
t0_set_out_mode(TO_B, TOM_00);
PORTD = (PORTD & ~_BV(PD5));
} else {
t0_set_out_mode(TO_B, TOM_10);
t0_set_ocr(TO_B, r);
}
if (g == 0x00) {
t0_set_out_mode(TO_A, TOM_00);
PORTD = (PORTD & ~_BV(PD6));
} else {
t0_set_out_mode(TO_A, TOM_10);
t0_set_ocr(TO_A, g);
}
if (b == 0x00) {
t2_set_out_mode(TO_B, TOM_00);
PORTD = (PORTD & ~_BV(PD3));
} else {
t2_set_out_mode(TO_B, TOM_10);
t2_set_ocr(TO_B, b);
}
}
void wheel(uint8_t pos) {
pos = 255 - pos;
if (pos < 85) {
set_rgb(255 - pos * 3, 0, pos * 3);
} else if (pos < 170) {
pos = pos - 85;
set_rgb(0, pos * 3, 255 - pos * 3);
} else {
pos = pos - 170;
set_rgb(pos * 3, 255 - pos * 3, 0);
}
}
const char* HEX_DIGIT = "0123456789ABCDEF";
#define BUFFERSIZE (1 + 6 + 1)
int main(void) {
// OC2B = PD3 → output
DDRD |= RGB_MASK;
uart_init();
t0_init_fpwm_3(PRESCALER_64);
t2_init_fpwm_3(PRESCALER_64);
t0_set_out_mode(TO_A | TO_B, TOM_00);
t2_set_out_mode(TO_B, TOM_00);
char buffer[BUFFERSIZE];
uint8_t cursor = 0;
uart_sendstring("RGB code:");
while (1) {
char data = uart_rx();
if (data == '\r') {
uart_sendstring("\r\n");
if (buffer[0] != '#')
uart_sendstring("Invalid code (#)\r\n");
else {
uint8_t buf[6] = {};
for (uint8_t i = 0; i < 6; i++)
buf[i] = ft_stridx(HEX_DIGIT, buffer[1 + i]);
bool valid = true;
for (uint8_t i = 0; i < 6; i++) {
if (buf[i] == 255)
valid = false;
}
if (valid) {
uint8_t r = 0, g = 0, b = 0;
r = (buf[1]) + ((buf[0]) * 16);
g = (buf[3]) + ((buf[2]) * 16);
b = (buf[5]) + ((buf[4]) * 16);
set_rgb(r, g, b);
} else {
uart_sendstring("Invalid code (N)\r\n");
}
}
// handle parsing;
cursor = 0;
ft_bzero(buffer, sizeof(buffer));
uart_sendstring("RGB code:");
continue;
}
if (data == '\x7f') {
if (cursor) {
buffer[cursor--] = 0;
uart_sendstring("\b \b");
}
continue;
}
if (data < ' ' || data > '~')
continue;
if (data >= 'a' && data <= 'z')
data -= 'a' - 'A';
if (cursor + 1 < BUFFERSIZE) {
uart_tx(data);
buffer[cursor++] = data;
}
}
}

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#include "uart.h"
#include <avr/io.h>
#include "mystd.h"
#include "utils.h"
#define BAUD_RATE 115200
#define UBRR_VALUE ((F_CPU / (8UL * BAUD_RATE)) - 1)
// uart is 115200 baud rate, 8 bits per word, no parrity and 1 stop bit
// 115200 8N1
void uart_init(void) {
// Set baud rate
UBRR0H = (uint8_t)(UBRR_VALUE >> 8);
UBRR0L = (uint8_t)(UBRR_VALUE);
UCSR0A |= _BV(U2X0);
// Enable transmitter
UCSR0B = _BV(TXEN0) | _BV(RXEN0) | _BV(RXCIE0);
// Set frame format: 8 data bits, no parity, 1 stop bit
UCSR0C = _BV(UCSZ01) | _BV(UCSZ00);
// Set TX (PD1) as output
DDRD |= _BV(PD1);
}
void uart_tx(char data) {
// wait for transmit buffer to be empty
while (!(UCSR0A & _BV(UDRE0)))
;
// load data into transmit register
UDR0 = data;
}
char uart_rx(void) {
while (!(UCSR0A & _BV(RXC0)))
;
return UDR0;
}
void uart_sendstring(const char* str) {
if (!str)
return;
while (*str) {
uart_tx(*str);
str++;
}
}
/*
void uart_send_u8(uint8_t val) {
char buf[4] = {0, 0, 0, 0};
uint8_t idx = 0;
bool print = false;
uint8_t modulus = 100;
while (modulus) {
uint8_t digit = val / modulus;
if (print || digit != 0) {
print = true;
buf[idx++] = '0' + digit;
}
val %= modulus;
modulus /= 10;
}
uart_sendstring(buf);
}
void uart_send_u16(uint16_t val) {
char buf[6] = {0, 0, 0, 0, 0, 0};
uint8_t idx = 0;
bool print = false;
uint16_t modulus = 10000;
while (modulus) {
uint8_t digit = val / modulus;
if (print || digit != 0) {
print = true;
buf[idx++] = '0' + digit;
}
val %= modulus;
modulus /= 10;
}
uart_sendstring(buf);
}
*/
void uart_send_u8_hex(uint8_t val) {
char buf[3] = {0, 0, 0};
buf[0] = "0123456789abcdef"[(val >> 4) & 0x0F];
buf[1] = "0123456789abcdef"[(val >> 0) & 0x0F];
uart_sendstring(buf);
}
/*
void uart_send_u16_hex(uint16_t val) {
char buf[5] = {0, 0, 0, 0, 0};
buf[0] = "0123456789abcdef"[(val >> 12) & 0x0F];
buf[1] = "0123456789abcdef"[(val >> 8) & 0x0F];
buf[2] = "0123456789abcdef"[(val >> 4) & 0x0F];
buf[3] = "0123456789abcdef"[(val >> 0) & 0x0F];
uart_sendstring(buf);
}
*/

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#include "utils.h"
#include "mystd.h"
// this just burns cycles.
// the volatile is important, it means that the cpu can't optimize any
// read/writes for the value
static inline void spin_loop(volatile uint16_t counts) {
while (counts)
counts--;
}
void delay_ms(uint16_t ms) {
while (ms) {
// this value was taken using a delay of 500ms, and just recording the led
// blinking. it seems to be high enough such that each loop of delay_loop
// takes 1ms :D
spin_loop((F_CPU) / 5000);
ms--;
}
}
void ft_bzero(void* data, uint16_t size) {
char* d = data;
while (size) {
*d = 0;
d++;
size--;
}
}
uint8_t ft_stridx(const char* str, char chr) {
if (!str)
return -1;
for (uint8_t i = 0; str[i]; i++) {
if (str[i] == chr)
return i;
}
return -1;
}