I have a problem with the AVR receiver problem.
The project consists of an ATmega88 which comunicates via an RS232 interface with a pc.
When I send data from the micro to the pc the datas received well but in the other way the micro does not.
I have seen the datas on the micro RXD pin with the oscilloscope. Also, the pin is set as an input (without pull up). Debuging using the MKII (debug wire) I see that the micro is going to the USART0 interrupt routine (RXCIE0 is set), but the data is always 0x00. When I check the UDR0 data in the RAM area is see that is 0x00 (address 0xC6).
I have check the RXD input as a digital inpout using a test routine and it's working well. I mean that it recognizes the logic 0 and logic 1.
Does anybody have an idea what I am not doing well?
Thank you very much.