The Fieldbus Foundation has announced the release of its AT-400 Device Description Tokenizer toolkit version 5.0 and the AT-401 Device Description Services toolkit version 5.0. These development toolkits enable instrumentation manufacturers to read and generate the Device Description (DD) files necessary for distribution with a Foundation Fieldbus device, and take advantage of new Electronic Device Description Language (EDDL) technology extensions in its fieldbus product development projects. EDDL is the superset specification of the descriptive technology language currently shared by the Fieldbus Foundation, Hart Communication Foundation and Profibus Nutzerorganisation e.V. The Fieldbus Foundation’s device development toolkits provide continuous support for the existing installed base of DDs while enabling implementation of the EDDL language extensions in future devices. Forward and backward compatibility is assured with EDDL’s leadership role and commitment to the existing DD technology’s binaries generated by the DD Tokenizer 4.x and 5.x products.