Re: [avr-chat] Trouble with USART0 on ATmega644A

[Daniel O'Connor]

On 06/01/2011, at 18:11, Rick Mann wrote:
> Hrm, I had the ATmega32A working just fine. But on the 644A I can't seem to 
> pin down the baud rate (or something else is wrong). According to the docs, 
> the '644A defaults to internal RC at 8 MHz. So, I've tried a number of 
> variations of settings, with U2X0 set and clear. Here's the latest:

Have you actually checked the fuses?

Read them out with avrdude then run them through 
http://www.engbedded.com/fusecalc/

Also, the '644A has 2 baud registers UBRRL & UBRRH for each UART according to 
http://www.atmel.com/dyn/resources/prod_documents/8272S.pdf

So I wonder if you are passing the right -mmcu arg?

--
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
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