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+# fw_ram
+RAM for the firmware (FW).
+
+
+## Introduction
+This core implements the RAM exclusive to the FW. This allows the FW
+to execute without having to use the application RAM. The core
+supports mode based lock down to prevent any access in application
+mode.
+
+
+## API
+The core does not have an API.
+
+
+## Implementation Details
+The core is implemented by explicitly instantiating one or more pairs
+of SB_RAM40_4K RAM cores in the FPGA.
+
+The contents of the fw_ram is cleared when the FPGA is powered up and
+configured by the bitstream. The contents is not cleared by a system
+reset.
+
+If the fw_app_mode input is set, no memory accesses are allowed. Any
+reads when the fw_app_mode is set will retun an all zero word.