The relationship between SOF, POF and Elf in NIOS __ios

SOF, POF and elf sof = FPGA internal SRAM configuration data, download through the JTAG, after the implementation of FPGA hardware function, after the electricity is evaporated.

POF = Configure the device flash data, download the as mode to configure the device, after power off, the FPGA will automatically read the configuration data from the configuration device, then configure the SRAM inside the FPGA to realize the hardware function of FPGA. If the design contains only the Nios hardware, after NIOS,POF configuration nios exist in the FPGA, Nios will be set in the preset memory space to run, if the designated Nios reset vector to SDRAM and SDRAM is empty, Nios will run away.

Elf = Nios software, which can be loaded into Nios ram via JTAG, can also be loaded into the configuration device (after Nios configuration data) through Epcs_controller (Programmer's Flash POF). If the reset vector of the nios points to the Epcs_controller,nios, the first instruction is executed from the configuration device.

In addition, POF files can be converted into JIC files and downloaded to EPCs in Jtag way, so hardware design can dispense with as configuration interfaces.