Fieldbus function block shell with user selectable data ownership

摘要

A method for accessing data on a fieldbus device in a fieldbus network which comprises user selectable models of data ownership. The fieldbus device includes a user application executing on the fieldbus device and a function block shell executing on the fieldbus device. The method comprises receiving a request to access data on a fieldbus device. In response to the request, the function block shell determines the ownership attribute of the data, wherein possible ownership attributes include user owned or shell owned. The shell accesses the data in response to determining that the ownership attribute of the data is shell owned. The user application accesses the data in response to determining that the ownership attribute of the data is user owned. The method further includes shell notify and user pointer ownership models which provide additional flexibility.