Patent ID: 8706995

Claim:
A field device for measuring one of a filling level, a pressure and a density of a medium in a container, comprising: a data memory storing data of first and second program modules, the data memory including at least two memory areas: a first memory area and a second memory area, the first area being separated from the second area, wherein the data of the first and second program modules includes first data and second data, the first data being required for a safe operation of the field device and categorized as safety-critical, the second data not being required for the safe operation of the field device and categorized as safety-uncritical, wherein the first memory area stores the first data and the second memory area only stores the second data, wherein the first program modules are categorized as safety-critical and have access to the data stored in the first memory area, wherein the second program modules are categorized as safety-uncritical and do not have access to the data stored in the first memory area, wherein a measured value is stored in the first memory area as well as in the second memory area, wherein the first memory area includes a first data of a first program module that is designed for executing a function that is selected from the group comprising at least one of determination of measured values as a function of sensor measuring data, derivation of additional measured values as a function of already determined measured values, and output of measured values, which the first program module is configured to access the measured value stored in the first memory area, and wherein the second memory area includes a second data of a second program module that is designed for executing a function that is selected from the group comprising at least one of recording measured values with status information as a function of the time and indicating measured values, which the second program module is configured to access the measured value stored in the second memory area.