Blank Canvas Cape is a Beaglebone cape that provides a Xlilinx Spartan 3A FPGA connected to the GPMC bus of the Beaglebone, 24 bits of user I/O, an on-board configuration memory for instant-on configuration, several user LEDs and buttons and SPI + I2C interfaces to the Beaglebone for configuration and control. In addition to the hardware, a user-space application and interface library is available for loading designs into the FPGA and configuration memory, as well as communicating with the FPGA after it is set up.
A more detailed description can be found at:
file:///home/ericb/KBADC/website/studionebula.com/embedded/bcc/index.html