There's a great bit of code on the Melabs site for using the hardware serial port and interrupts. It creates a ring buffer that automatically collects the incoming serial data. When your program is ready, it can average the data that is in the ring buffer and display it. If you need to display every little change of the variable, then you would display a "snapshot" of the last 10, 20, or 128 values that were captured. The ring buffer continually overwrites itself, so if there was a specific event, you can stop it, or just read values on the fly. Take a look at "serA452.bas". I tip my hat to whomever wrote it.