Hello everyone, I am learning how to use header files with UART on ATmega8. I have two problems: First one for some reason the registers like identifier “UBRR0L” is undefined and the rest of them. And the second one is it does not include the header file. I dont know if these two problem are related…

[image] aleksandar.jevtic666: void UartPutchar(char data) { while(!(UCSR0A & (1 << UDRE0))); UDR0 = data; } Your topic title says ATmega8, but per https://sites.google.com/site/qeewiki/books/avr-guide/usart [grafik] the register only exists for the devices that have multiple UART ports. …

aleksandar.jevtic666 April 5, 2021, 2:33pm 6

That did resolve the library problem, but I still have undefined registers?

UART identifier "UBRR0H" is undefined (ATmega 8)