Embedded web server for the AVR Butterfly enabling immediate access to wireless sensor node readings

Abstract

The "AVR Butterfly" (BF) is not just a microcontroller, but rather an autonomous embedded system kit including several sensors. Our main objective was first to provide Internet connectivity to the BF and then to evaluate its further capabilities as a sensor network node. To this end, we equipped the BF with a TCP/IP stack and a Zigbee transceiver. As a case study, we constructed a node and a gateway based on the BF and formed a simple wireless sensor network (WSN). In order to enable remote users to access, on demand, sensor node readings through their web browsers, an HTML Server application was developed for the BF-gateway. We demonstrate that despite the scarcity of the available resources, if we enhance the BF with a popular Ethernet chip and the optimal TCP/IP stack for 8-bit microcontrollers, we can obtain a powerful, yet simple and inexpensive, monitoring device with Internet connectivity capabilities. © Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering 2010.