Abstract
Tapper is a lightweight scripting engine for highly constrained wireless sensor nodes. Many such nodes run on 8-bit microcontrollers (MCUs) with only a few kilobytes of on-chip memory, often with segmented memory and unorthogonal registers that make it difficult to perform even the most basic tasks. To facilitate development of software routines and enable dynamic reconfigurability, Tapper provides a software layer that can interpret human readable commands either interactively or in batch. It can invoke compiled routines ranging from timer and interrupt configurations and task scheduling to accessing I/O devices. Experiments on platforms including 8051, ATMega 169V, and Freescale MC9S12NE64 with built-in Ethernet show that the Tapper setup has the same modular, dynamic benefits as middleware systems but without the high overhead in code size and data memory. Copyright 2006 ACM.