This is simple demo program of reading button state, lighting LEDs, sending information via USART. 8 buttons are connected to Atmega16 port A, 8 LEDs to port B via current limiting resistors. While none of buttons arent pressed there is running light on LEDs performed, but when any of buttons is pressed then LEDs display current 8 buit counter value in binary format. Same value is sent via USART – you can see number in terminal if connected.
The program is very simple:
#include <avr/io.h>
#include <util/delay.h>
#include <stdio.h>
#ifndef F_CPU
#define F_CPU 1000000
#endif
//set desired baud rate
#define BAUDRATE 9600
//calculate UBRR value
#define UBRRVAL ((F_CPU/(BAUDRATE*16UL))-1)
char n, //number
c; //current state of display
int main(void)
{
//Set baud rate
UBRRL=UBRRVAL; //low byte
UBRRH=(UBRRVAL>>8); //high byte
//Set data frame format: asynchronous mode,no parity, 1 stop bit, 8 bit size For more detail: Output number when button is pressed using Atmega16 microcontroller
