-- Calculate the CRC-16-CCITT checksum for an array of bytes

-- Copyright (C)2025, Philip Munts dba Munts Technologies.
--
-- Redistribution and use in source and binary forms, with or without
-- modification, are permitted provided that the following conditions are met:
--
-- * Redistributions of source code must retain the above copyright notice,
--   this list of conditions and the following disclaimer.
--
-- THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-- AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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WITH Interfaces; USE Interfaces;

GENERIC

  TYPE Octet       IS MOD <>;
  TYPE IndexType   IS RANGE <>;
  TYPE BufferType  IS ARRAY (IndexType) OF Octet;

  Seed : Unsigned_16 := 16#1D0F#;

FUNCTION CRC16_CCITT(buf : BufferType; len : Natural) RETURN Unsigned_16;