I'm interfacing GPS module with LPC2378. The GPS module is sending data continuously and the packet size is more than 100 bytes. The receiver buffer's(RBR) size is 16 bytes. As soon as GPS module is connected to LPC's UART, the first 16 bytes are placed in RBR and the remaining bytes of GPS module is lost. The LSR(Line Status Register) shows overrun error. I tried using interrupts whenever ready data is available in RX line. But even in this case, LSR shows overrun error. How to receive all the bytes from GPS module in LPC2378 without overrun error?
You're not stopping the code in the debugger and then manually checking registers, are you?
You need to check the chip documentation, but the UART probably continues to receive characters - then, if the debugger's stopped the code, you obviously will get an overrun error!