Abstract: This document shows how Dallas Semiconductor/Maxim's SHA iButtons® and 1-Wire® devices can be used with small microcontrollers to provide strong encryption and authentication of control and status messages, telemetry, or sensitive process control information. For low cost and low overhead, it provides nonvolatile memory, secure secret storage, secret sharing and rotation, fast SHA-1 pad generation, and a globally unique serial number. A simple microcontroller needs only provide a single port pin and a few dozen lines of code to attain quality cryptographic security. The application note you have requested is available in Acrobat PDF format: APPLICATION NOTE 150: Small Message Encryption using SHA Devices (PDF, 121kB) A free Acrobat PDF reader is available from: http://www.adobe.com/products/acrobat/readstep.html We Want Your Feedback! Automatic Updates Would you like to be automatically notified when new application notes are published in your areas of interest? Sign up for EE-Mail™. More Information   APP 150: Feb 04, 2002 DS1961S 1kb Protected EEPROM iButton with SHA-1 Engine   DS1963S SHA iButton DS2432 1Kb Protected 1-Wire EEPROM with SHA-1 Engine Abridged Data Sheet (PDF, 408kB)   Download, PDF Format (121kB)  AN150, AN 150, APP150, Appnote150, Appnote 150