From 4976af6a8458b8263abceb19368e95688031fb9a Mon Sep 17 00:00:00 2001
From: brett <brett@bretts-windows-laptop>
Date: Thu, 25 Apr 2024 00:09:09 -0500
Subject: doooone

---
 final_project/serial.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

(limited to 'final_project/serial.c')

diff --git a/final_project/serial.c b/final_project/serial.c
index bb5b58f..7a230ef 100644
--- a/final_project/serial.c
+++ b/final_project/serial.c
@@ -5,14 +5,19 @@
  *  Author: bsw9xd
  */ 
 #include "serial.h"
+
+#define F_CPU 16000000UL
+#define BAUD 9600 //standard minimum baud rate
 
 void usart_init() {
-	volatile int ubrr = (F_CPU / (16UL * BAUD)) - 1; //TODO: why is this volatile int???
+	volatile int ubrr = (F_CPU / (16UL * BAUD)) - 1;
 	UCSR1A = 0; //async normal communication
+	//enable transmission/reception
 	UCSR1B = (1 << TXEN) | (1 << RXEN);
+	//8 bits per packet, no parity, 1 stop bit
 	UCSR1C = (1 << UCSZ0) | (1 << UCSZ1);
 	
-	
+	//set baud rate
 	UBRR1H = (unsigned char)(ubrr << 8);
 	UBRR1L = (unsigned char)ubrr;
 }
@@ -23,17 +28,16 @@ void usart_txt(char data) { //transmit data
 	
 }
 char usart_rxt() {
-	if(UCSR1A & (1 << RXC)) {
-		return UDR1;
-	}
-	return '\0';
+	if(UCSR1A & (1 << RXC)) { return UDR1; } //attempt to get input,
+	return '\0'; //if there is none, then return null char
 }
 
-char usart_rxt_blocking() { //TODO maybe replace usart_txt
-	while(!(UCSR1A & (1 << RXC))); //TODO simplify
+char usart_rxt_blocking() {
+	while(!(UCSR1A & (1 << RXC)));  //wait for input via polling
 	return UDR1;
 }
 
 void usart_txstr(char *str) {
+	//transmit strong character by character untill null terminator
 	for(int i = 0; str[i] != '\0'; i++) usart_txt(str[i]);
 }
-- 
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