From 1229352c64ce277ac515ac1d42979902d8f8100b Mon Sep 17 00:00:00 2001
From: Alexey Zholtikov <git@zh.com.ru>
Date: Sun, 10 Aug 2025 20:42:19 +0300
Subject: [PATCH] wip:

---
 .gitignore |  4 ++++
 src/main.c | 25 +++++++++++++++++++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 src/main.c

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..df66652
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+.pio
+.vscode
+.DS_Store
+platformio.ini
\ No newline at end of file
diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..745c555
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,25 @@
+#include "avr/io.h"
+#include "stdio.h"
+
+#define BAUD_RATE 9600
+#define BAUD_PRESCALE (F_CPU / 16 / BAUD_RATE - 1)
+
+int usart(char byte, FILE *stream)
+{
+	while ((UCSR0A & (1 << UDRE0)) == 0)
+	{
+	}
+	UDR0 = byte;
+	return 0;
+}
+FILE uart = FDEV_SETUP_STREAM(usart, NULL, _FDEV_SETUP_WRITE);
+
+int main(void)
+{
+	UBRR0H = (BAUD_PRESCALE >> 8);
+	UBRR0L = BAUD_PRESCALE;
+	UCSR0B = (1 << RXEN0) | (1 << TXEN0);
+	UCSR0C = (1 << UCSZ01) | (1 << UCSZ00);
+	stdout = &uart;
+	return 0;
+}
\ No newline at end of file