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Multimedia applications commonly require high computation power mostly in conjunction with high data throughput. As an additional challenge, such applications are increasingly used in handheld devices, where also small package outlines and low power aspects are important. Many research approaches have shown, that accelerators based on reconfigurable hardware can satisfy those performance demands.Most of these approaches use commercial fine-grained FPGAs to implement reconfigurable accelerators. However, it has shown, that these devices are not always well suited for reconfigurable computing. The drawbacks here are the area-inefficiency and the insufficiency of the available design-tools. Besides the fine-grained FPGAs, coarse-grained reconfigurable architectures have been developed, which are more area efficient and better suited for computational purposes. In this paper, an implementation of such an architecture, the KressArray, is introduced and its use in the Map-oriented Machine with Parallel Data Access (MoM-PDA) is shown. The MoM-PDA is an FPGA-based custom computing machine, which is able to perform concurrent memory accesses by means of a dedicated memory organization scheme. The benefits of this architecture are illustrated by an application example.

8In a joint experimental and theoretical effort, we carried out a detailed study of electron scattering from Kr atoms in the energy range of the low-lying Kr − (4p 5 5s2 ) Feshbach resonances. Absolute angle-differential cross sections for elastic electron scattering were measured over the energy range 9.3−10.3 eV with an energy width of about 13 meV at scattering angles between 10• and 180• . Using several sets of elastic scattering phase shifts, a detailed analysis of the sharp Kr − (4p 5 5s 2 2 P 3/2 ) resonance was carried out, resulting in a resonance width of Γ 3/2 = 3.6(2) meV. By direct comparison with the position of the Ar − (3p 5 4s 2 2 P 3/2 ) resonance, the energy for the Kr − (4p 5 5s 2 2 P 3/2 ) resonance was determined as E 3/2 = 9.489(3) eV. A Fano-type fit of the higher-lying Kr − (4p 5 5s 2 2 P 1/2 ) resonance yielded the resonance parameters Γ 1/2 = 33(5) meV and E 1/2 = 10.126(4) eV. In order to obtain additional insight, B-spline R-matrix calculations were performed for both the elastic and the inelastic cross sections above the threshold for 4p 5 5s excitation. They provide the total and angle differential cross sections for excitation of long-lived and short lived levels of the 4p 5 5s configuration in Kr and branching ratios for the decay of the Kr − (4p 5 5s 2 2 P 1/2 ) resonance into the three available exit channels. The results are compared with selected experimental data.

This paper introduces a CAD environment for design-space exploration of coarse grain reconfigurable KressArray architectures and similar platforms. To find an optimal solution to a given application domain this KressArray Xplorer supports experimenting with different architectures. An estimator analyses the input and suggests an architecture onto which then the application is mapped using an heuristic algorithm. A graphic editor supports user interaction. The system generates performance analysis data, which is used by an automatic tool to refine the result iteratively.