Author: Abbott, M.G.
Paper Title Page
MOPGF097 Architecture of Transverse Multi-Bunch Feedback Processor at Diamond 1
 
  • M.G. Abbott, G. Rehm, I.S. Uzun
    DLS, Oxfordshire, United Kingdom
 
  We describe the detailed internal architecture of the Transverse Multi-Bunch Feedback processor used at Diamond for control of multi-bunch instabilities and measurement of betatron tunes. Bunch by bunch selectable control over feedback filters, gain and excitation allows fine control over feedback, allowing for example the single bunch in a hybrid or camshaft fill pattern to be controlled independently from the bunch train. It is also possible to excite all bunches at a single frequency while simultaneously sweeping the excitation for tune measurement of a few selected bunches. The single frequency excitation has been used for continuous measurement of the beta-function. A simple programmable event sequencer provides support for up to 7 steps of programmable sweeps and changes to feedback and excitation, allowing a variety of complex and precisely timed beam characterisation experiments including grow-damp measurements in unstable conditions and programmed bunch cleaning. Finally input and output compensation filters allow for correction of front end and amplifier phasing at higher frequencies.  
poster icon Poster MOPGF097 [0.247 MB]  
 
WEPGF089 CERN Open Hardware Experience: Upgrading the Diamond Fast Archiver 1
 
  • I.S. Uzun, M.G. Abbott
    DLS, Oxfordshire, United Kingdom
 
  Diamond Light Source developed and integrated the Fast Archiver into its Fast Orbit Feedback communication network in 2009. It enabled synchronous capture and archive of the entire position data in real-time from all Electron Beam Position Monitors (BPMs) and X-RAY BPMs . The FA Archiver solution has also been adopted by SOLEIL and ESRF. However, the obsolescence of the existing PCI Express based FPGA board from Xilinx and continuing interest from community forced us to look for a new hardware platform while keeping the back compatibility with the existing Linux kernel driver and application software. This paper reports our experience with using the PCIe SPEC board from CERN Open Hardware initiative as the new FA Archiver platform. Implementation of the SPEC-based FA Archiver has been successfully completed and recently deployed at ALBA in Spain.  
poster icon Poster WEPGF089 [0.576 MB]