This report presents the implementation of hierarchical scheduling framework HSF on an open source real-time operating system FreeRTOS to support the temporal isolation of a number of real-time components (or applications) onto a single processor. The goal is to achieve predictable integration and reusability of independently developed components or tasks. It presents the initial results of the HSF implementation by running it on an AVR 32-bit board EVK1100. It addresses the fixed-priority preemptive scheduling at both global and local scheduling levels. It describes the detailed design of HSF with the emphasis of doing minimal changes to the underlying FreeRTOS kernel and keeping its API intact. Finally it provides (and compares) the results for the performance measures of periodic and deferrable servers with respect to the overhead of the implementation. Index Terms: real-time systems; hierarchical scheduling framework; fixed-priority scheduling