When using the SAM7S256 demo source (which has a task created for Tx and Rx on USART0), it is possible to cause the Tx task to stop. The way I caused this failure was to hold down any key (yes, the “any key”) on the keyboard for long periods of time. Sometimes I had to release the key and then hold it down again. However, it doesn’t take long before the transmitter stops transmitting to the serial port.
If someone has one of the other serial examples running on a different processor (or an Atmel processor), would you try to see if you can cause the RTOS to stop sending data? In the example demo a string of characters (A through X) is output continuously.
What I am hoping is that there is a simple solution to this problem. I will eventually need a serial port that can transmit and receive data at 230400 baud simultaneously and without error.