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Teufelchen1Teufelchen1
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Merge pull request #21552 from Teufelchen1/feat/crc16fcs
checksum: Add crc16-fcs / IBM-SDLC
2 parents b1296af + 65fc4b0 commit 734c570

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‎sys/checksum/crc16_ccitt.c‎

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@@ -123,6 +123,21 @@ uint16_t crc16_ccitt_mcrf4xx_calc(const unsigned char *buf, size_t len)
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return crc16_ccitt_kermit_update(0xFFFF, buf, len);
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}
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uint16_t crc16_ccitt_fcs_start(const unsigned char *buf, size_t len)
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{
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return crc16_ccitt_kermit_update(0xFFFF, buf, len);
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}
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uint16_t crc16_ccitt_fcs_finish(uint16_t crc, const unsigned char *buf, size_t len)
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{
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return crc16_ccitt_kermit_update(crc, buf, len) ^ 0xFFFFU;
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}
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uint16_t crc16_ccitt_fcs_calc(const unsigned char *buf, size_t len)
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{
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return crc16_ccitt_fcs_start(buf, len) ^ 0xFFFFU;
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}
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uint16_t crc16_ccitt_false_update(uint16_t crc, const unsigned char *buf, size_t len)
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{
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while (len--) {

‎sys/include/checksum/crc16_ccitt.h‎

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@@ -71,6 +71,71 @@ uint16_t crc16_ccitt_kermit_update(uint16_t crc, const unsigned char *buf, size_
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*/
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uint16_t crc16_ccitt_kermit_calc(const unsigned char *buf, size_t len);
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/**
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* @brief Start a CRC16-CCITT-FCS / IBM-SDLC calculation
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*
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* @param[in] buf Start of the memory area to checksum
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* @param[in] len Number of bytes to checksum
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*
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* @return Partial checksum of the specified memory area. To be finalised
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* with crc16_ccitt_fcs_finish()
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*/
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uint16_t crc16_ccitt_fcs_start(const unsigned char *buf, size_t len);
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/**
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* @brief Update CRC16-CCITT-FCS / IBM-SDLC
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*
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* @param[in] crc A start value for the CRC calculation, usually the
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* return value of a previous call to
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* crc16_ccitt_fcs_start() or crc16_ccitt_fcs_update()
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* @param[in] buf Start of the memory area to checksum
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* @param[in] len Number of bytes to checksum
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*
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* @return Partial checksum of the specified memory area based on the
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* given start value. To be finalised with crc16_ccitt_fcs_finish()
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*/
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static inline uint16_t crc16_ccitt_fcs_update(uint16_t crc, const unsigned char *buf,
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size_t len)
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{
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/* Since CCITT-KERMIT and CCITT-FCS only differ in the starting
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* seed, we wrap around crc16_ccitt_kermit_update() for updating */
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return crc16_ccitt_kermit_update(crc, buf, len);
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}
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/**
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* @brief Finalise CRC16-CCITT-FCS / IBM-SDLC
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*
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* @param[in] crc A start value for the CRC calculation, usually the
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* return value of a previous call to
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* crc16_ccitt_fcs_start() or crc16_ccitt_fcs_update()
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* @param[in] buf Start of the memory area to checksum
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* @param[in] len Number of bytes to checksum
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*
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* @return Checksum of the specified memory area based on the
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* given start value.
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*/
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uint16_t crc16_ccitt_fcs_finish(uint16_t crc, const unsigned char *buf, size_t len);
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/**
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* @brief Calculate CRC16-CCITT-FCS / IBM-SDLC in one pass.
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*
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* Parameter | Value
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* --------: | :----
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* Polynom | `0x1021`
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* Init | `0xffff`
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* Refin | `true`
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* Refout | `true`
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* Xorout | `0xffff`
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* Check | `0x906e`
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* Residue | `0xf0b8`
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*
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* @param[in] buf Start of the memory area to checksum
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* @param[in] len Number of bytes to checksum
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*
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* @return Checksum of the specified memory area
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*/
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uint16_t crc16_ccitt_fcs_calc(const unsigned char *buf, size_t len);
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/**
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* @brief Update CRC16-CCITT-MCRF4XX
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*

‎tests/unittests/tests-checksum/tests-checksum-crc16-ccitt-false.c‎

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@@ -1,5 +1,5 @@
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/*
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* Copyright 2022 Bennet Blischke <[email protected]>
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* Copyright 2022 Bennet Hattesen <[email protected]>
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*
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* This file is subject to the terms and conditions of the GNU Lesser
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* General Public License v2.1. See the file LICENSE in the top level

‎tests/unittests/tests-checksum/tests-checksum-crc16-ccitt-fcs.c‎

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@@ -0,0 +1,126 @@
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/*
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* Copyright 2025 Bennet Hattesen <[email protected]>
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*
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* This file is subject to the terms and conditions of the GNU Lesser
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* General Public License v2.1. See the file LICENSE in the top level
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* directory for more details.
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*/
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#include <stdio.h>
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#include <stdint.h>
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#include "embUnit/embUnit.h"
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#include "checksum/crc16_ccitt.h"
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#include "tests-checksum.h"
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static int calc_and_compare_crc16_ccitt_fcs_with_update(const unsigned char *buf,
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size_t len, size_t split,
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uint16_t expected)
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{
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uint16_t result = crc16_ccitt_fcs_start(buf, split);
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result = crc16_ccitt_fcs_finish(result, buf + split, len - split);
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return result == expected;
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}
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static int calc_and_compare_crc16_ccitt_fcs(const unsigned char *buf, size_t len,
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uint16_t expected)
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{
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uint16_t result = crc16_ccitt_fcs_calc(buf, len);
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return result == expected;
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}
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static void test_checksum_crc16_ccitt_fcs_sequence_empty(void)
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{
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unsigned char buf[] = "";
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uint16_t expect = 0x0000;
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs(buf, sizeof(buf) - 1, expect));
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs_with_update(buf, sizeof(buf) - 1,
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(sizeof(buf) - 1) / 2, expect));
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}
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static void test_checksum_crc16_ccitt_fcs_sequence_1a(void)
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{
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unsigned char buf[] = "A";
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uint16_t expect = 0xA3F5;
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs(buf, sizeof(buf) - 1, expect));
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs_with_update(buf, sizeof(buf) - 1,
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(sizeof(buf) - 1) / 2, expect));
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}
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static void test_checksum_crc16_ccitt_fcs_sequence_256a(void)
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{
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unsigned char buf[] = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
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"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
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"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
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"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
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"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
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"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
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"AAAA";
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uint16_t expect = 0x0F9F;
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs(buf, sizeof(buf) - 1, expect));
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs_with_update(buf, sizeof(buf) - 1,
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(sizeof(buf) - 1) / 2, expect));
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}
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static void test_checksum_crc16_ccitt_fcs_sequence_1to9(void)
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{
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unsigned char buf[] = "123456789";
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uint16_t expect = 0x906E;
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs(buf, sizeof(buf) - 1, expect));
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs_with_update(buf, sizeof(buf)
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- 1, (sizeof(buf) - 1) / 2,
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expect));
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}
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static void test_checksum_crc16_ccitt_fcs_sequence_4bytes(void)
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{
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unsigned char buf[] = { 0x12, 0x34, 0x56, 0x78 };
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uint16_t expect = 0x9B2E;
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs(buf, sizeof(buf), expect));
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs_with_update(buf, sizeof(buf),
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sizeof(buf) / 2, expect));
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}
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static void test_checksum_crc16_ccitt_fcs_sequence_6bytes(void)
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{
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unsigned char buf[] = { 0x00, 0x01, 0x02, 0x03 };
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uint16_t expect = 0xA729;
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs(buf, sizeof(buf), expect));
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs_with_update(buf, sizeof(buf),
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sizeof(buf) / 2, expect));
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unsigned char buf2[] = { 0x00, 0x01, 0x02, 0x03, 0x29, 0xA7 };
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uint16_t expect2 = 0x0F47;
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// Residue test
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TEST_ASSERT(crc16_ccitt_fcs_start(buf2, sizeof(buf2)) == 0xF0B8);
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs(buf2, sizeof(buf2), expect2));
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TEST_ASSERT(calc_and_compare_crc16_ccitt_fcs_with_update(buf2, sizeof(buf2),
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sizeof(buf2) / 2, expect2));
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}
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Test *tests_checksum_crc16_ccitt_fcs_tests(void)
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{
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EMB_UNIT_TESTFIXTURES(fixtures) {
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new_TestFixture(test_checksum_crc16_ccitt_fcs_sequence_empty),
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new_TestFixture(test_checksum_crc16_ccitt_fcs_sequence_1a),
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new_TestFixture(test_checksum_crc16_ccitt_fcs_sequence_256a),
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new_TestFixture(test_checksum_crc16_ccitt_fcs_sequence_1to9),
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new_TestFixture(test_checksum_crc16_ccitt_fcs_sequence_4bytes),
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new_TestFixture(test_checksum_crc16_ccitt_fcs_sequence_6bytes),
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};
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EMB_UNIT_TESTCALLER(checksum_crc16_ccitt_fcs_tests, NULL, NULL, fixtures);
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return (Test *)&checksum_crc16_ccitt_fcs_tests;
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}

‎tests/unittests/tests-checksum/tests-checksum-crc16-ccitt-kermit.c‎

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@@ -1,5 +1,5 @@
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/*
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* Copyright 2022 Bennet Blischke <[email protected]>
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* Copyright 2022 Bennet Hattesen <[email protected]>
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*
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* This file is subject to the terms and conditions of the GNU Lesser
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* General Public License v2.1. See the file LICENSE in the top level

‎tests/unittests/tests-checksum/tests-checksum-crc16-ccitt-mcrf4xx.c‎

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@@ -1,5 +1,5 @@
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/*
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* Copyright 2022 Bennet Blischke <[email protected]>
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* Copyright 2022 Bennet Hattesen <[email protected]>
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*
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* This file is subject to the terms and conditions of the GNU Lesser
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* General Public License v2.1. See the file LICENSE in the top level

‎tests/unittests/tests-checksum/tests-checksum.c‎

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@@ -13,6 +13,7 @@ void tests_checksum(void)
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TESTS_RUN(tests_checksum_crc8_tests());
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TESTS_RUN(tests_checksum_crc8_lsb_tests());
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TESTS_RUN(tests_checksum_crc16_ccitt_kermit_tests());
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TESTS_RUN(tests_checksum_crc16_ccitt_fcs_tests());
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TESTS_RUN(tests_checksum_crc16_ccitt_mcrf4xx_tests());
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TESTS_RUN(tests_checksum_crc16_ccitt_aug_tests());
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TESTS_RUN(tests_checksum_crc16_ccitt_false_tests());

‎tests/unittests/tests-checksum/tests-checksum.h‎

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@@ -50,6 +50,13 @@ Test *tests_checksum_crc8_lsb_tests(void);
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*/
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Test *tests_checksum_crc16_ccitt_kermit_tests(void);
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/**
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* @brief Generates tests for crc16-ccitt-fcs from checksum/crc16_ccitt.h
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*
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* @return embUnit tests if successful, NULL if not.
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*/
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Test *tests_checksum_crc16_ccitt_fcs_tests(void);
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/**
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* @brief Generates tests for crc16-ccitt-mcrf4xx from checksum/crc16_ccitt.h
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*

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