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+This directory contains support RTL code for the modexp core. The code
+here is not directly part of the core RTL.
+
+montprod_wrapper.v
+  A simple wrapper to mux together inputs and outputs from the montprod
+  module. Used for test builds of versions of montprod with different
+  (64, 128,2 256 bits) operand widths which means that the interface
+  from the montprod can contain a huge number of bits and thus pins.
+
+
+blockmem_rw32ptr_r64.v
+  A synchronous block memory with two separate ports and internal
+  address generator as used in the modex_core to implement the exponent,
+  modulus and message memories. This version sports a 64 bit wide data
+  port for core internal read access while the API facing interface uses
+  32 bit wide data. When the modexp is set to use 64 bit operands, this
+  module should be included into the src/rtl dir to be used in the
+  modexp_core instantiation of the block memory.