Maxim Integrated Analog Essentials Getting Started Guide for LX9 and Nexys3 - Manual (Page 8)

Analog Essentials Getting Started Guide
8
For LX9 and Nexys-3
It takes approximately 10 seconds to download the FPGA and a message box indicating “FPGA
configuration complete” will appear.
A brief note summarizing the previous steps:
As discussed earlier in this document, the code size of this program exceeds that available in block
memory internal to the FPGA, necessitating the use of the external RAM. This requires a multi-stage
loading process implemented with a boot-loader. This operates a bit differently from smaller programs
where the entire FPGA configuration data and executable code is contained in one .bit file and is loaded
in one step
The bitstream (.bit) file is used to configure the FPGA and initiate the bootloading process. This
bitstream contains all the configuration information necessary to initialize the FPGA with the gate level
hardware design, including block memories, which are used for the base Microblaze memory.
The (.bmm) file provides the location of block RAM memories (internal to the FPGA) that are used as
codespace for the Microblaze. The (.elf) file contains the instructions that represent the Microblaze
executable program. That file will be loaded into external pseudostatic RAM (PSRAM) using the Xilinx
debugger in a subsequent step, right after we set up PC communications in the next step.