The VM-USB and CC-USB main Xilinx FPGA chips load their configuration from an EEPROM. The EEPROM can be programmed over the USB interface. The ccusbloader and vmusbloader programs provided by and redistributed with the permission of Wiener-Plein Baus are programs that program the FPGA load EEPROMS.
These loaders work both with Xilinx .bit and .bin files.
The XX-USB devices have four load locations. Which one runs and which one is programmed is selected by the rotary switch on the XX-USB front panel.
XX-USB load procedure
Select a program location (1-4) by pointing to the appropriate P1,2,3,4 location with the front panel rotary switch.
Run the appropriate loader as per the documentation in the reference section linked to above.
Select the run location of the firmware by selecting the appropriate C1,2,3,4 location with the rotary switch
Double check that the device will start that firmware by cycling power on the VME/CAMAC crate.
Once you have checked that the firmware performs as expected, you can program all firmware locations by following the above procedure three more times selecting different P locations until all have been programmed.