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authorXavier ASUS <xavi92psx@gmail.com>2019-10-18 00:31:54 +0200
committerXavier ASUS <xavi92psx@gmail.com>2019-10-18 00:31:54 +0200
commit268a53de823a6750d6256ee1fb1e7707b4b45740 (patch)
tree42c1799a9a82b2f7d9790ee9fe181d72a7274751 /device/lib/pic16/libc/stdlib/crc16.c
downloadsdcc-gas-268a53de823a6750d6256ee1fb1e7707b4b45740.tar.gz
sdcc-3.9.0 fork implementing GNU assembler syntax
This fork aims to provide better support for stm8-binutils
Diffstat (limited to 'device/lib/pic16/libc/stdlib/crc16.c')
-rw-r--r--device/lib/pic16/libc/stdlib/crc16.c83
1 files changed, 83 insertions, 0 deletions
diff --git a/device/lib/pic16/libc/stdlib/crc16.c b/device/lib/pic16/libc/stdlib/crc16.c
new file mode 100644
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+++ b/device/lib/pic16/libc/stdlib/crc16.c
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+/*-------------------------------------------------------------------------
+ crc16.c - CRC16 checksum generation
+
+ Copyright (C) 2005, Vangelis Rokas <vrokas at otenet.gr>
+
+ This library 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, or (at your option) any
+ later version.
+
+ This library 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 library; see the file COPYING. If not, write to the
+ Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
+ MA 02110-1301, USA.
+
+ As a special exception, if you link this library with other files,
+ some of which are compiled with SDCC, to produce an executable,
+ this library does not by itself cause the resulting executable to
+ be covered by the GNU General Public License. This exception does
+ not however invalidate any other reasons why the executable file
+ might be covered by the GNU General Public License.
+-------------------------------------------------------------------------*/
+
+/*
+ * The CRC code was devised by Don P. Mitchell of AT&T Bell Laboratories
+ * and Ned W. Rhodes of Software Systems Group. It has been published in
+ * "Design and Validation of Computer Protocols", Prentice Hall,
+ * Englewood Cliffs, NJ, 1991, Chapter 3, ISBN 0-13-539925-4.
+ *
+ * Copyright is held by AT&T.
+ *
+ * AT&T gives permission for the free use of the CRC source code.
+ */
+
+#include <stdint.h>
+
+__code uint16_t crc_table[256] = {
+ 0x0000U, 0x1021U, 0x2042U, 0x3063U, 0x4084U, 0x50a5U, 0x60c6U, 0x70e7U,
+ 0x8108U, 0x9129U, 0xa14aU, 0xb16bU, 0xc18cU, 0xd1adU, 0xe1ceU, 0xf1efU,
+ 0x1231U, 0x0210U, 0x3273U, 0x2252U, 0x52b5U, 0x4294U, 0x72f7U, 0x62d6U,
+ 0x9339U, 0x8318U, 0xb37bU, 0xa35aU, 0xd3bdU, 0xc39cU, 0xf3ffU, 0xe3deU,
+ 0x2462U, 0x3443U, 0x0420U, 0x1401U, 0x64e6U, 0x74c7U, 0x44a4U, 0x5485U,
+ 0xa56aU, 0xb54bU, 0x8528U, 0x9509U, 0xe5eeU, 0xf5cfU, 0xc5acU, 0xd58dU,
+ 0x3653U, 0x2672U, 0x1611U, 0x0630U, 0x76d7U, 0x66f6U, 0x5695U, 0x46b4U,
+ 0xb75bU, 0xa77aU, 0x9719U, 0x8738U, 0xf7dfU, 0xe7feU, 0xd79dU, 0xc7bcU,
+ 0x48c4U, 0x58e5U, 0x6886U, 0x78a7U, 0x0840U, 0x1861U, 0x2802U, 0x3823U,
+ 0xc9ccU, 0xd9edU, 0xe98eU, 0xf9afU, 0x8948U, 0x9969U, 0xa90aU, 0xb92bU,
+ 0x5af5U, 0x4ad4U, 0x7ab7U, 0x6a96U, 0x1a71U, 0x0a50U, 0x3a33U, 0x2a12U,
+ 0xdbfdU, 0xcbdcU, 0xfbbfU, 0xeb9eU, 0x9b79U, 0x8b58U, 0xbb3bU, 0xab1aU,
+ 0x6ca6U, 0x7c87U, 0x4ce4U, 0x5cc5U, 0x2c22U, 0x3c03U, 0x0c60U, 0x1c41U,
+ 0xedaeU, 0xfd8fU, 0xcdecU, 0xddcdU, 0xad2aU, 0xbd0bU, 0x8d68U, 0x9d49U,
+ 0x7e97U, 0x6eb6U, 0x5ed5U, 0x4ef4U, 0x3e13U, 0x2e32U, 0x1e51U, 0x0e70U,
+ 0xff9fU, 0xefbeU, 0xdfddU, 0xcffcU, 0xbf1bU, 0xaf3aU, 0x9f59U, 0x8f78U,
+ 0x9188U, 0x81a9U, 0xb1caU, 0xa1ebU, 0xd10cU, 0xc12dU, 0xf14eU, 0xe16fU,
+ 0x1080U, 0x00a1U, 0x30c2U, 0x20e3U, 0x5004U, 0x4025U, 0x7046U, 0x6067U,
+ 0x83b9U, 0x9398U, 0xa3fbU, 0xb3daU, 0xc33dU, 0xd31cU, 0xe37fU, 0xf35eU,
+ 0x02b1U, 0x1290U, 0x22f3U, 0x32d2U, 0x4235U, 0x5214U, 0x6277U, 0x7256U,
+ 0xb5eaU, 0xa5cbU, 0x95a8U, 0x8589U, 0xf56eU, 0xe54fU, 0xd52cU, 0xc50dU,
+ 0x34e2U, 0x24c3U, 0x14a0U, 0x0481U, 0x7466U, 0x6447U, 0x5424U, 0x4405U,
+ 0xa7dbU, 0xb7faU, 0x8799U, 0x97b8U, 0xe75fU, 0xf77eU, 0xc71dU, 0xd73cU,
+ 0x26d3U, 0x36f2U, 0x0691U, 0x16b0U, 0x6657U, 0x7676U, 0x4615U, 0x5634U,
+ 0xd94cU, 0xc96dU, 0xf90eU, 0xe92fU, 0x99c8U, 0x89e9U, 0xb98aU, 0xa9abU,
+ 0x5844U, 0x4865U, 0x7806U, 0x6827U, 0x18c0U, 0x08e1U, 0x3882U, 0x28a3U,
+ 0xcb7dU, 0xdb5cU, 0xeb3fU, 0xfb1eU, 0x8bf9U, 0x9bd8U, 0xabbbU, 0xbb9aU,
+ 0x4a75U, 0x5a54U, 0x6a37U, 0x7a16U, 0x0af1U, 0x1ad0U, 0x2ab3U, 0x3a92U,
+ 0xfd2eU, 0xed0fU, 0xdd6cU, 0xcd4dU, 0xbdaaU, 0xad8bU, 0x9de8U, 0x8dc9U,
+ 0x7c26U, 0x6c07U, 0x5c64U, 0x4c45U, 0x3ca2U, 0x2c83U, 0x1ce0U, 0x0cc1U,
+ 0xef1fU, 0xff3eU, 0xcf5dU, 0xdf7cU, 0xaf9bU, 0xbfbaU, 0x8fd9U, 0x9ff8U,
+ 0x6e17U, 0x7e36U, 0x4e55U, 0x5e74U, 0x2e93U, 0x3eb2U, 0x0ed1U, 0x1ef0U
+};
+
+uint16_t crc16(uint8_t *data, uint32_t size, uint16_t crc)
+{
+ while (size--)
+ crc = crc_table[((crc >> 8) ^ *(data++)) & 0xffU] ^ (crc << 8);
+
+ return crc;
+}