The Use of FPGAS as a Platform for Distributed Control Systems,” ICALEPCS’05

With the advances in Field Programmable Gate Array (FPGA) capacity and design tools, it has become feasible to consolidate into one small package both application specific control functions and a general purpose embedded processor (complete with various network interfaces). Such a package is now capable of performing the same role in a control system as the typical bus-based system such as VME. The Advanced Light Source completed an upgrade to the electronics for the Stanford Linear Accelerator PEP2 bunch-by-bunch Transverse Feedback (TFB) system [1]. The new TFB board uses a Xilinx VirtexII-Pro XC2VP7 FPGA to receive 12-bit ADC data, perform a configurable digital filtering, and finally output a 12-bit value to a DAC; all of this runs at 238MHz. Parameter and mode setting of the FPGA feedback system are controlled through a sockets interface (or alternatively through EPICS [2]) running on the embedded PowerPC hardcore in the same VP7. The TFB board is derived from the Xilinx ML300 demonstration board; the 128Mbyte DDR interface, 10/100 Ethernet, RS-232, System ACE/200MByte micro hardrive FileSystem, and non-volatile RAM interfaces are identical to the ML300. We describe using the Xilinx Embedded Device Kit to build the FPGA hardware, followed by the generation of the VxWorks Board Support Package for the hardware design