Performs processing in response to detection of overrun error.
| This API function is called as the callback routine of interrupt process r_uartn_interrupt_receive corresponding to the UART reception end interrupt INTSRn (process performed when the amount of data received is greater than the argument rx_num specified for R_UARTn_Receive). | 
| uint16_t rx_data; | Receive data (greater than the argument rx_num specified for R_UARTn_Receive) |