I have a custom DSP board which has a UART port to send data to PC. Strange thing is when I stop the UART port on DSP, PC still continues to receive data. Even stranger, I unplugged the USB cable from PC so there is no connection between the board and PC, still terminal is receiving data and it doesn't stop for 10 minutes! Do you know what's going on? I hooked up Oscope to DSP UART TX port, it was in-active.
It sounds as if the data from the UART is being buffered and your program is not retrieving data fast enough from the buffer to keep it level. At 115k baud, 10 minutes of buffered data would indicate a buffer of ~ 700k bytes.