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+#ifndef ucoolib_utils_crc_hh
+#define ucoolib_utils_crc_hh
+// ucoolib - Microcontroller object oriented library. {{{
+//
+// Copyright (C) 2013 Nicolas Schodet
+//
+// APBTeam:
+// Web: http://apbteam.org/
+// Email: team AT apbteam DOT org
+//
+// This program 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 2 of the License, or
+// (at your option) any later version.
+//
+// This program 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.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+//
+// }}}
+#include "ucoolib/common.hh"
+
+namespace ucoo {
+
+/// Dallas/Maxim iButton 8bit CRC.
+/// Polynomial: x^8 + x^5 + x^4 + 1
+/// Initial value: 0
+static inline uint8_t
+crc8_update (uint8_t crc, uint8_t data)
+{
+ uint8_t i;
+ crc = crc ^ data;
+ for (i = 0; i < 8; i++)
+ {
+ if (crc & 0x01)
+ crc = (crc >> 1) ^ 0x8C;
+ else
+ crc >>= 1;
+ }
+ return crc;
+}
+
+uint8_t
+crc8_compute (const uint8_t *data, int size);
+
+} // namespace ucoo
+
+#endif // ucoolib_utils_crc_hh