1 files changed, 105 insertions, 0 deletions
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..abc31d4
--- /dev/null
+++ b/main.c
@@ -0,0 +1,105 @@
+#define F_CPU 8000000UL
+
+#include <avr/io.h>
+#include <stdlib.h>
+#include <util/delay.h>
+
+#define PIN_LED PB0
+#define NUM_LEDS 50
+
+struct led {
+	unsigned char r, g, b;
+};
+
+void signal_high() {
+	asm volatile (
+		"sbi %0, %1\n\t"
+		"rjmp .+0\n\t"
+		"nop\n\t"
+		"cbi %0, %1\n\t"
+		"rjmp .+0\n\t"
+		"rjmp .+0\n\t"
+		:
+		: "I" (_SFR_IO_ADDR(PORTB)), "I" (PIN_LED)
+	);
+}
+
+void signal_low() {
+	asm volatile (
+		"sbi %0, %1\n\t"
+		"cbi %0, %1\n\t"
+		"rjmp .+0\n\t"
+		"rjmp .+0\n\t"
+		"rjmp .+0\n\t"
+		"nop\n\t"
+		:
+		: "I" (_SFR_IO_ADDR(PORTB)), "I" (PIN_LED)
+	);
+}
+
+void signal_byte(unsigned char byte) {
+	for (unsigned char mask = 0x80; mask != 0; mask >>= 1) {
+		if (byte & mask)
+			signal_high();
+		else
+			signal_low();
+	}
+}
+
+void signal_led(struct led *led) {
+	signal_byte(led->r);
+	signal_byte(led->g);
+	signal_byte(led->b);
+}
+
+void signal_led_sequence(int num_leds, struct led **seq, int num_seq) {
+	for(int i = 0; i < num_leds; ++i) {
+		int j = i % num_seq;
+		signal_led(seq[j]);
+	}
+}
+
+int main() {
+	DDRB |= (1 << PIN_LED);
+	PORTB &= ~(1 << PIN_LED);
+
+	struct led **seq = calloc(3, sizeof(*seq)); 
+
+	seq[0] = calloc(1, sizeof(struct led));
+	seq[1] = calloc(1, sizeof(struct led));
+	seq[2] = calloc(1, sizeof(struct led));
+
+	while (1) {
+		seq[0]->g = 0;
+		seq[1]->b = 0;
+		seq[2]->r = 0;
+		seq[0]->r = 255;
+		seq[1]->g = 255;
+		seq[2]->b = 255;
+
+		signal_led_sequence(NUM_LEDS, seq, 3);
+		_delay_ms(250);
+
+		seq[0]->r = 0;
+		seq[1]->g = 0;
+		seq[2]->b = 0;
+		seq[0]->b = 255;
+		seq[1]->r = 255;
+		seq[2]->g = 255;
+
+		signal_led_sequence(NUM_LEDS, seq, 3);
+		_delay_ms(250);
+
+		seq[0]->b = 0;
+		seq[1]->r = 0;
+		seq[2]->g = 0;
+		seq[0]->g = 255;
+		seq[1]->b = 255;
+		seq[2]->r = 255;
+
+		signal_led_sequence(NUM_LEDS, seq, 3);
+		_delay_ms(250);
+	}
+
+	return 0;
+}