About the BRAM Initial Content Updater

The BRAM Initial Content Updater is a tool that lets you quickly update the initial memory saved in the FPGA's BRAM without performing a full compile. For example, you can use this tool if you want to:
  • Update RISC-V application code in the on-chip memory
  • Update sensor parameters in on-chip memory

To open the BRAM Initial Content Updater, click its icon in the toolbar or choose Tools > Open BRAM Initial Content Updater.

Figure 1. Using the Netlist Pane

In the tool, you select the elaborated netlist memory that you want to update, not the post-map memory. Therefore, you do not need to know how synthesis decomposes and maps the memories to use this tool. Because this tool bypasses the full compilation flow, it does not update <project>.map.v and other intermediate compiler output files. As a result, the updated bitstream file will be out of sync with your other project files.

The format of the initial memory files is the same format used by Verilog HDL parsers and the $readmemh or $readmemb Verilog HDL functions.

Note: The --optimize-zero-init-rom synthesis option tells the software to optimize away zero value ROMs. If your design has zero-value ROMs and you plan to use the BRAM Initial Content Updater later, disable this synthesis option in your project settings.
Figure 2. BRAM Initial Content Updater