Generally softcores are used for command and control for the FPGA. For eg you have a framegrabber and you would like to adjust the shutter speed, fps etc you wo

Generally softcores are used for command and control for the FPGA. For eg you have a framegrabber and you would like to adjust the shutter speed, fps etc you would create a softcore and run normal firmware to setup the registers based on the users choice. You can think of FPGA as an ASIC and the softcore to control this ASIC. The hot data path and heavy processing is done in the FPGA and processing options for the ASIC can be done using the softcore firmware.