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(* BitWordOps.def provides a Logitech-3.0 compatible library.
Copyright (C) 2007-2025 Free Software Foundation, Inc.
Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.
This file is part of GNU Modula-2.
GNU Modula-2 is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
GNU Modula-2 is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. *)
DEFINITION MODULE BitWordOps ;
FROM SYSTEM IMPORT WORD ;
(*
GetBits - returns the bits firstBit..lastBit from source.
Bit 0 of word maps onto the firstBit of source.
*)
PROCEDURE GetBits (source: WORD; firstBit, lastBit: CARDINAL) : WORD ;
(*
SetBits - sets bits in, word, starting at, firstBit, and ending at,
lastBit, with, pattern. The bit zero of, pattern, will
be placed into, word, at position, firstBit.
*)
PROCEDURE SetBits (VAR word: WORD; firstBit, lastBit: CARDINAL;
pattern: WORD) ;
(*
WordAnd - returns a bitwise (left AND right)
*)
PROCEDURE WordAnd (left, right: WORD) : WORD ;
(*
WordOr - returns a bitwise (left OR right)
*)
PROCEDURE WordOr (left, right: WORD) : WORD ;
(*
WordXor - returns a bitwise (left XOR right)
*)
PROCEDURE WordXor (left, right: WORD) : WORD ;
(*
WordNot - returns a word with all bits inverted.
*)
PROCEDURE WordNot (word: WORD) : WORD ;
(*
WordShr - returns a, word, which has been shifted, count
bits to the right.
*)
PROCEDURE WordShr (word: WORD; count: CARDINAL) : WORD ;
(*
WordShl - returns a, word, which has been shifted, count
bits to the left.
*)
PROCEDURE WordShl (word: WORD; count: CARDINAL) : WORD ;
(*
WordSar - shift word arthemetic right. Preserves the top
end bit and as the value is shifted right.
*)
PROCEDURE WordSar (word: WORD; count: CARDINAL) : WORD ;
(*
WordRor - returns a, word, which has been rotated, count
bits to the right.
*)
PROCEDURE WordRor (word: WORD; count: CARDINAL) : WORD ;
(*
WordRol - returns a, word, which has been rotated, count
bits to the left.
*)
PROCEDURE WordRol (word: WORD; count: CARDINAL) : WORD ;
(*
HighByte - returns the top byte only from, word.
The byte is returned in the bottom byte
in the return value.
*)
PROCEDURE HighByte (word: WORD) : WORD ;
(*
LowByte - returns the low byte only from, word.
The byte is returned in the bottom byte
in the return value.
*)
PROCEDURE LowByte (word: WORD) : WORD ;
(*
Swap - byte flips the contents of word.
*)
PROCEDURE Swap (word: WORD) : WORD ;
END BitWordOps.
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