The VM-USB is a VME master with high speed USB2 interface. Enhanced functionality is given by the programmable internal FPGA logic which provides a VME command sequencer with 4kB stack and 28kB data buffer. Combined with the 4 front panel I/O ports this allows VME operation and data acquisition / buffering without any PC or USB activity.
All VM-USB logic is controlled by the XILINX Spartan 3 family FPGA. Upon power-up the FPGA boots from a flash memory. The configuration flash memory can be reprogrammed via the USB port, allowing convenient updates of the firmware. Following an open platform approach the user can develop his own FPGA configuration.