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1 1 - 0 = 1 1 + 1 = 0 1 - 1 = 0 椤劧锛屽姞鍜屾笡鏄竴妯ｇ殑鏁堟灉锛堟晠鍦℅F锛�2锛夊闋�(xi脿ng)寮忎腑涓€鑸笉鍑虹従(xi脿n)"-"铏�(h脿o)锛�锛岄兘绛夊悓浜庣暟鎴栭亱(y霉n)绠椼€備緥 濡侾1 = x锔�3 + x锔�2 + 1锛孭2 = x锔�3 + x锔�1 + 1锛孭1 + P2鐐猴細 x锔�3 + x锔�2 銆€銆€+ 1 + x锔�3 + x + 1 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€� x锔�2 + x GF锛�2锛夊闋�(xi脿ng)寮忎箻娉曞拰涓€鑸闋�(xi脿ng)寮忎箻娉曞熀鏈竴妯ｏ紝鍙槸鍦ㄥ悇闋�(xi脿ng)鐩稿姞鐨勬檪(sh铆)鍊欐寜妯�2绠楄(sh霉)閫�(j矛n)琛�锛屼緥濡� P1 锛� P2鐐猴細 锛坸锔�3 + x锔�2 + 1锛夛紙x锔�3 + x锔�1 + 1锛� = 锛坸锔�6 + x锔�4 + x锔�3 + x锔�5 + x锔�3 + x锔�2 + x锔�3 + x + 1锛� = x锔�6 + x锔�5 + x锔�4 + x锔�3 + x锔�2 + x + 1 GF锛�2锛夊闋�(xi脿ng)寮忛櫎娉曚篃鍜屼竴鑸闋�(xi脿ng)寮忛櫎娉曞熀鏈竴妯ｏ紝鍙槸鍦ㄥ悇闋�(xi脿ng)鐩告笡鐨勬檪(sh铆)鍊欐寜妯�2绠楄(sh霉)閫�(j矛n)琛�锛屼緥 濡侾3 = x锔�7 + x锔�6 + x锔�5 + x锔�2 + x锛孭3 / P2鐐猴細 x锔�4 + x锔�3 + 1 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€� x锔�3 + x + 1 锛墄锔�7 + x锔�6 + x锔�5 + x锔�2 + x x锔�7 + x锔�5 + x锔�4 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€�- x锔�6 + x锔�4 x锔�6 + x锔�4 + x锔�3 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€�- x锔�3 + x锔�2 + x x锔�3 + x + 1 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€�- x锔�2 + 1 CRC绠楁硶灏囬暦(zh菐ng)搴︾偤m浣嶇殑娑堟伅灏�(du矛)鎳�(y墨ng)涓€鍊�(g猫)GF锛�2锛夊闋�(xi脿ng)寮廙锛屾瘮濡傚皪(du矛)浜�8浣嶆秷鎭�11100110锛屽鏋滃厛鍌宠几MSB锛屽墖瀹冨皪(du矛)鎳�(y墨ng)鐨勫闋�(xi脿ng)寮忕偤x锔�7 + x锔�6 + x锔�5 + x锔�2 + x銆傜櫦(f膩)閫佺鍜屾帴鏀剁绱勫畾涓€鍊�(g猫)娆℃暩(sh霉)鐐簉鐨凣F锛�2锛夊闋�(xi脿ng)寮廏锛岀ū(ch膿ng)鐐虹敓鎴愬闋�(xi脿ng)寮�锛屾瘮濡倄锔�3 + x + 1锛宺 = 3銆傚湪娑堟伅鍚庨潰鍔犱笂r鍊�(g猫)0灏�(du矛)鎳�(y墨ng)鐨勫闋�(xi脿ng)寮忕偤M鈥�锛岄’鐒舵湁M鈥� = Mx锔縭銆傜敤M鈥欓櫎浠灏囧緱鍒颁竴鍊�(g猫)娆℃暩(sh霉)绛変簬鎴栧皬浜巖 - 1鐨勪綑鏁�(sh霉)澶氶爡(xi脿ng)寮廟锛屽叾灏�(du矛)鎳�(y墨ng)鐨剅浣嶆暩(sh霉)鍊煎墖鐐烘牎椹�(y脿n)纰笺€傚涓嬫墍绀猴細 11001100 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€�- 1011 锛�11100110000 1011....... 鈥斺€斺€斺€�....... 1010...... 1011...... 鈥斺€斺€斺€�...... 1110... 1011... 鈥斺€斺€斺€�... 1010.. 1011.. 鈥斺€斺€斺€� 100 <鈥斺€�-鏍￠(y脿n)纰� 鐧�(f膩)閫佺灏噈浣嶆秷鎭€ｅ悓r浣嶆牎椹�(y脿n)纰硷紙涔熷氨鏄疢鈥� + R锛変竴璧风櫦(f膩)閫佸嚭鍘�锛屾帴鏀剁鎸夊悓妯ｇ殑鏂规硶绠楀嚭鏀跺埌鐨刴浣嶆秷鎭殑鏍￠(y脿n)纰�锛屽啀鑸囨敹鍒扮殑鏍￠(y脿n)纰兼瘮杓冦€傛帴鏀剁涔熷彲浠ョ敤鏀跺埌鐨勫叏閮╩ + r浣嶉櫎浠ョ敓鎴愬闋�(xi脿ng)寮�锛屽啀鍒ゆ柗浣欐暩(sh霉)鏄惁鐐�0銆傞€欐槸鍥�?y脿n)?锛孧鈥� + R = 锛圦G + R锛� + R = QG锛岄€欓噷Q鏄晢銆傞’鐒�锛屽畠涔熷彲浠ュ儚鐧�(f膩)閫佺涓€妯�锛屽湪鍏ㄩ儴m + r鍚庡啀澧炲姞r鍊�(g猫)0锛屽啀闄や互鐢熸垚澶氶爡(xi脿ng)寮忥紝濡傛灉娌�(m茅i)鏈夊樊閷�(cu貌)鐧�(f膩)鐢�锛屼綑鏁�(sh霉)浠嶇劧鐐�0銆� 3.鐢熸垚澶氶爡(xi脿ng)寮忕殑閬告搰 寰堟槑椤�锛屼笉鍚岀殑鐢熸垚澶氶爡(xi脿ng)寮�锛屽叾妾㈤尟(cu貌)鑳藉姏鏄笉鍚岀殑銆傚浣曢伕鎿囦竴鍊�(g猫)濂界殑鐢熸垚澶氶爡(xi脿ng)寮忛渶瑕佷竴瀹氱殑鏁�(sh霉)瀛�(xu茅)鐞嗚珫锛岄€欓噷鍙緸涓€浜涘伌(c猫)闈綔浜涘垎鏋愩€傞’鐒�锛岃浣跨敤r浣嶆牎椹�(y脿n)纰硷紝鐢熸垚澶氶爡(xi脿ng)寮忕殑娆℃暩(sh霉)鎳�(y墨ng)鐐簉銆傜敓鎴愬闋�(xi脿ng)寮忔噳(y墨ng)瑭插寘鍚爡(xi脿ng)"1"锛屽惁鍓囨牎椹�(y脿n)纰肩殑LSB锛圠east Significant Bit锛夊皣濮嬬祩鐐�0銆傚鏋滄秷鎭紙鍖呮嫭鏍￠(y脿n)纰硷級T鍦ㄥ偝杓搁亷(gu貌)绋嬩腑鐢�(ch菐n)鐢熶簡宸尟(cu貌)锛屽墖鎺ユ敹绔敹鍒扮殑娑堟伅鍙互琛ㄧず鐐篢(m茅n) + E銆傝嫢E涓嶈兘琚敓鎴愬闋�(xi脿ng)寮廏闄ょ洝锛屽墖瑭插樊閷�(cu貌)鍙互琚娓�(c猫)鍑�?锛熺搐]浠ヤ笅骞剧ó鎯呮硜锛� 1锛�1浣嶅樊閷�(cu貌)锛屽嵆E = x锔縩 = 100...00锛宯 >= 0銆傚彧瑕丟鑷冲皯鏈�2浣�1锛孍灏变笉鑳借G闄ょ洝銆傞€� 鏄洜?y脿n)闀歺锔縦鐩哥暥(d膩ng)浜庡皣G宸︾Щk浣嶏紝灏�(du矛)浠绘剰澶氶爡(xi脿ng)寮廞锛孮G鐩哥暥(d膩ng)浜庡皣澶氬€�(g猫)涓嶅悓鐨凣鐨勫乏绉荤浉鍔�銆� 濡傛灉G鑷冲皯鏈夊叐浣�1锛屽畠鐨勫鍊�(g猫)涓嶅悓鐨勫乏绉荤浉鍔犵祼(ji茅)鏋滆嚦灏戞湁鍏╀綅1銆� 2锛夊鏁�(sh霉)浣嶅樊閷�(cu貌)锛屽彧瑕丟鍚湁鍥犲瓙F = x + 1锛孍灏变笉鑳借G闄ょ洝銆傞€欐槸鍥�?y脿n)闀糋 = Q鈥橣锛岀敱1锛� 鐨勫垎鏋�锛孎(xi脿n)鐨勫鍊�(g猫)涓嶅悓鐨勫乏绉荤浉鍔犵祼(ji茅)鏋�1鐨勪綅鏁�(sh霉)蹇呯劧鏄伓鏁�(sh霉)銆� 3锛夌垎鐐告€у樊閷�(cu貌)锛屽嵆E = 锛坸锔縩 + ... + 1锛墄锔縨 = 1...100...00锛宯 >= 1锛宮 >= 0锛岄’鐒跺彧 瑕丟鍖呭惈闋�(xi脿ng)"1"锛屼笖娆℃暩(sh霉)澶т簬n锛屽氨涓嶈兘闄ょ洝E銆� 4锛�2浣嶅樊閷�(cu貌)锛屽嵆E = 锛坸锔縩 + 1锛墄锔縨 = 100...00100...00锛宯 >= 0銆傝ō(sh猫)x锔縩 + 1 = QG + R锛� 鍓嘐 = QGx锔縨 + Rx锔縨锛岀敱3锛夊彲鐭鑳借G闄ょ洝鐣�(d膩ng)涓斿儏鐣�(d膩ng)R鐐�0銆傚洜姝ゅ彧闇€鍒嗘瀽x锔縩 + 1锛屾牴鎿�(j霉)[3]锛屽皪(du矛)浜庢鏁�(sh霉)r锛岀附瀛樺湪涓€鍊�(g猫)鐢熸垚澶氶爡(xi脿ng)寮廏锛屼娇寰梟鏈€灏忕偤2锔縭 - 1鏅�(sh铆)锛屾墠鑳介櫎鐩锔縩 + 1銆傜ū(ch膿ng)瑭茬敓鎴愬闋�(xi脿ng)寮忔槸鍘熷鐨勶紙primitive锛�锛屽畠鎻愪緵浜嗗湪瑭叉鏁�(sh霉)涓婃娓�(c猫)2浣嶅樊閷�(cu貌)鐨勬渶楂樿兘鍔涳紝鍥�?y脿n)妤�?d膩ng)n = 2锔縭 - 1鏅�(sh铆)锛寈锔縩 + 1鑳借浠讳綍r娆″闋�(xi脿ng)寮忛櫎鐩�銆俒3]鍚屾檪(sh铆)鎸囧嚭锛屽師濮嬬敓鎴愬闋�(xi脿ng)寮忔槸涓嶅彲绱勫垎鐨�锛屼絾涓嶅彲绱勫垎鐨勭殑澶氶爡(xi脿ng)寮忓苟涓嶄竴瀹氭槸鍘熷鐨�锛屽洜姝ゅ皪(du矛)浜庢煇浜涘鏁�(sh霉)浣嶅樊閷�(cu貌)锛屽師濮嬬敓鎴愬闋�(xi脿ng)寮忔槸妾㈡脯(c猫)涓嶅嚭渚�(l谩i)鐨�銆� 浠ヤ笅鏄竴浜涙(bi膩o)婧�(zh菙n)鐨凜RC绠楁硶鐨勭敓鎴愬闋�(xi脿ng)寮忥細 妯�(bi膩o)婧�(zh菙n) 澶氶爡(xi脿ng)寮� 16閫�(j矛n)鍒惰〃绀� CRC12 x锔�12 + x锔�11 + x锔�3 + x锔�2 + x + 1 80F CRC16 x锔�16 + x锔�15 + x锔�2 + 1 8005 CRC16-CCITT x锔�16 + x锔�12 + x锔�5 + 1 1021 CRC32 x锔�32 + x锔�26 + x锔�23 + x锔�22 + x锔�16 + x锔�12 + x锔�11 04C11DB7 + x锔�10 + x锔�8 + x锔�7 + x锔�5 + x锔�4 + x锔�2 + x + 1 16閫�(j矛n)鍒惰〃绀哄幓鎺変簡鏈€楂樻闋�(xi脿ng)锛孋CITT鍦�1993骞存敼鍚嶇偤ITU-T銆侰RC12鐢ㄤ簬6浣嶅瓧绡€(ji茅)锛屽叾瀹冪敤浜�8浣嶅瓧绡€(ji茅)銆侰RC16鍦↖BM鐨凚ISYNCH閫氫俊妯�(bi膩o)婧�(zh菙n)銆侰RC16-CCITT琚唬娉涚敤浜嶺MODEM, X.25鍜孲DLC绛夐€氫俊鍗�(xi茅)璀�銆傝€屼互澶恫(w菐ng)鍜孎DDI鍓囦娇鐢–RC32锛屽畠涔熻鐢ㄥ湪ZIP锛孯AR绛夋枃浠跺绺腑銆傚湪閫欎簺鐢熸垚澶氶爡(xi脿ng)寮忎腑锛孋RC32鏄師濮嬬殑锛岃€屽叾瀹�3鍊�(g猫)閮藉惈鏈夊洜瀛恱 + 1銆� 4.CRC绠楁硶鐨勫(sh铆)鐝�(xi脿n) 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€�- 瑕佺敤绋嬪簭?q奴)宕縁(xi脿n)CRC绠楁硶锛岃€冩叜灏�(du矛)绗�2绡€(ji茅)鐨勯暦(zh菐ng)闄ゆ硶鍋氫竴涓嬭畩鎻涳紝渚濈劧鏄疢 = 11100110锛孏 = 1011锛屽叾绯绘暩(sh霉)r鐐�3銆� 11001100 11100110000 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€斺€�- 1011 1011 锛�11100110000 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€�- 1011....... 1010110000 鈥斺€斺€斺€�....... 1010110000 1010...... 1011 1011...... ===> 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€�- 鈥斺€斺€斺€�...... 001110000 1110... 1110000 1011... 1011 鈥斺€斺€斺€�... 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€�- 1010.. 101000 1011.. 101000 鈥斺€斺€斺€� 1011 100 <鈥斺€�-鏍￠(y脿n)纰� 鈥斺€斺€斺€斺€斺€斺€斺€斺€斺€�- 00100 100 <鈥斺€�-鏍￠(y脿n)纰� 绋嬪簭鍙互濡備笅瀵�(sh铆)鐝�(xi脿n)锛� 1锛夊皣Mx锔縭鐨勫墠r浣嶆斁鍏ヤ竴鍊�(g猫)闀�(zh菐ng)搴︾偤r鐨勫瘎瀛樺櫒锛� 2锛夊鏋滃瘎瀛樺櫒鐨勯浣嶇偤1锛屽皣瀵勫瓨鍣ㄥ乏绉�1浣嶏紙灏嘙x锔縭鍓╀笅閮ㄥ垎鐨凪SB绉诲叆瀵勫瓨鍣ㄧ殑LSB锛�锛屽啀鑸嘒鐨勫悗r浣嶇暟鎴�锛屽惁鍓囧儏灏囧瘎瀛樺櫒宸︾Щ1浣嶏紙灏嘙x锔縭鍓╀笅閮ㄥ垎鐨凪SB绉诲叆瀵勫瓨鍣ㄧ殑LSB锛�锛� 3锛夐噸寰�(f霉)绗�2姝ワ紝鐩村埌M鍏ㄩ儴Mx锔縭绉诲叆瀵勫瓨鍣�锛� 4锛夊瘎瀛樺櫒涓殑鍊煎墖鐐烘牎椹�(y脿n)纰�銆� 鐢–RC16-CCITT鐨勭敓鎴愬闋�(xi脿ng)寮�0x1021锛屽叾C浠ｇ⒓锛堟湰鏂囨墍鏈変唬纰煎亣瀹氱郴绲�(t菕ng)鐐�32浣�锛屼笖閮藉湪VC6涓婄法璀€氶亷(gu貌)锛夊涓嬶細 unsigned short do_crc锛坲nsigned char 锛妋essage, unsigned int len锛� 锝� int i, j; unsigned short crc_reg; crc_reg = 锛坢essage[0] << 8锛� + message[1]; for 锛坕 = 0; i < len; i++锛� 锝� if 锛坕 < len - 2锛� for 锛坖 = 0; j <= 7; j++锛� 锝� if 锛堬紙short锛塩rc_reg < 0锛� crc_reg = 锛堬紙crc_reg << 1锛� + 锛坢essage[i + 2] >> 锛�7 - i锛夛級锛� 锔� 0x1021; else crc_reg = 锛坈rc_reg << 1锛� + 锛坢essage[i + 2] >> 锛�7 - i锛夛級; 锝� else for 锛坖 = 0; j <= 7; j++锛� 锝� if 锛堬紙short锛塩rc_reg < 0锛� crc_reg = 锛坈rc_reg << 1锛� 锔� 0x1021; else crc_reg <<= 1; 锝� 锝� return crc_reg; 锝� 椤劧锛屾瘡娆″収(n猫i)寰挵(hu谩n)鐨勮鐐哄彇姹轰簬瀵勫瓨鍣ㄩ浣�銆傜敱浜庣暟鎴栭亱(y霉n)绠楁豢(m菐n)瓒充氦鎻涚巼鍜岀祼(ji茅)鍚堝緥锛屼互鍙婅垏0鐣� 鎴栫劇(w煤)褰遍熆锛屾秷鎭彲浠ヤ笉绉诲叆瀵勫瓨鍣�锛岃€屽湪姣忔鍏�(n猫i)寰挵(hu谩n)鐨勬檪(sh铆)鍊�锛屽瘎瀛樺櫒棣栦綅鍐嶈垏灏�(du矛)鎳�(y墨ng)鐨勬秷鎭綅鐣版垨銆傛敼閫�(j矛n)鐨勪唬纰煎涓嬶細 unsigned short do_crc锛坲nsigned char 锛妋essage, unsigned int len锛� 锝� int i, j; unsigned short crc_reg = 0; unsigned short current; for 锛坕 = 0; i < len; i++锛� 锝� current = message[i] << 8; for 锛坖 = 0; j < 8; j++锛� 锝� if 锛堬紙short锛夛紙crc_reg 锔� current锛� < 0锛� crc_reg = 锛坈rc_reg << 1锛� 锔� 0x1021; else crc_reg <<= 1; current <<= 1; 锝� 锝� return crc_reg; 锝� 浠ヤ笂鐨勮◣璜栦腑锛屾秷鎭殑姣忓€�(g猫)瀛楃瘈(ji茅)閮芥槸鍏堝偝杓窶SB锛孋RC16-CCITT妯�(bi膩o)婧�(zh菙n)鍗绘槸鎸夌収鍏堝偝杓窵SB锛屾秷鎭彸绉婚€�(j矛n)瀵勫瓨鍣ㄤ締(l谩i)瑷�(j矛)绠楃殑銆傚彧闇€灏囦唬纰兼敼鎴愬垽鏂峰瘎瀛樺櫒鐨凩SB锛屽皣0x1021鎸変綅椤涘€掑悗锛�0x8408锛夎垏瀵勫瓨鍣ㄧ暟鎴栧嵆鍙紝濡備笅鎵€绀猴細 unsigned short do_crc锛坲nsigned char 锛妋essage, unsigned int len锛� 锝� int i, j; unsigned short crc_reg = 0; unsigned short current; for 锛坕 = 0; i < len; i++锛� 锝� current = message[i]; for 锛坖 = 0; j < 8; j++锛� 锝� if 锛堬紙crc_reg 锔� current锛� & 0x0001锛� crc_reg = 锛坈rc_reg >> 1锛� 锔� 0x8408; else crc_reg >>= 1; current >>= 1; 锝� 锝� return crc_reg; 锝� 瑭茬畻娉曚娇鐢ㄤ簡鍏╁堡寰挵(hu谩n)锛屽皪(du矛)娑堟伅閫愪綅閫�(j矛n)琛岃檿鐞�锛岄€欐ǎ鏁堢巼鏄緢浣庣殑銆傜偤浜嗘彁楂樻檪(sh铆)闁撴晥鐜�锛岄€氬父鐨勬€濇兂鏄互绌洪枔鎻涙檪(sh铆)闁�?锛熺搐]鍒板収(n猫i)寰挵(hu谩n)鍙垏鐣�(d膩ng)鍓嶇殑娑堟伅瀛楃瘈(ji茅)鍜宑rc_reg鐨勪綆瀛楃瘈(ji茅)鏈夐棞(gu膩n)锛屽皪(du矛)瑭茬畻娉曞仛浠ヤ笅绛夋晥杞�(zhu菐n)鎻涳細 unsigned short do_crc锛坲nsigned char 锛妋essage, unsigned int len锛� 锝� int i, j; unsigned short crc_reg = 0; unsigned char index; unsigned short to_xor; for 锛坕 = 0; i < len; i++锛� 锝� index = 锛坈rc_reg 锔� message[i]锛� & 0xff; to_xor = index; for 锛坖 = 0; j < 8; j++锛� 锝� if 锛坱o_xor & 0x0001锛� to_xor = 锛坱o_xor >> 1锛� 锔� 0x8408; else to_xor >>= 1; 锝� crc_reg = 锛坈rc_reg >> 8锛� 锔� to_xor; 锝� return crc_reg; 锝� 鐝�(xi脿n)鍦ㄥ収(n猫i)寰挵(hu谩n)鍙垏index鐩搁棞(gu膩n)浜�锛屽彲浠ヤ簨鍏堜互鏁�(sh霉)绲勫舰寮忕敓鎴愪竴鍊�(g猫)琛╟rc16_ccitt_table锛屼娇寰梩o_xor = crc16_ccitt_table[index]锛屼簬鏄彲浠ョ啊(ji菐n)鍖栫偤锛� unsigned short do_crc锛坲nsigned char 锛妋essage, unsigned int len锛� 锝� unsigned short crc_reg = 0; while 锛坙en鈥斺€旓級 crc_reg = 锛坈rc_reg >> 8锛� 锔� crc16_ccitt_table[锛坈rc_reg 锔� 锛妋essage++锛� & 0xff]; return crc_reg; 锝� crc16_ccitt_table閫氶亷(gu貌)浠ヤ笅浠ｇ⒓鐢熸垚锛� int main锛堬級 锝� unsigned char index = 0; unsigned short to_xor; int i; printf锛�"unsigned short crc16_ccitt_table[256] =\n锝�"锛�; while 锛�1锛� 锝� if 锛�!锛坕ndex % 8锛夛級 printf锛�"\n"锛�; to_xor = index; for 锛坕 = 0; i < 8; i++锛� 锝� if 锛坱o_xor & 0x0001锛� to_xor = 锛坱o_xor >> 1锛� 锔� 0x8408; else to_xor >>= 1; 锝� printf锛�"0x%04x", to_xor锛�; if 锛坕ndex == 255锛� 锝� printf锛�"\n"锛�; break; 锝� else 锝� printf锛�", "锛�; index++; 锝� 锝� printf锛�"锝�;"锛�; return 0; 锝� 鐢熸垚鐨勮〃濡備笅锛� unsigned short crc16_ccitt_table[256] = 锝� 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78 锝�; 閫欐ǎ灏�(du矛)浜庢秷鎭痷nsigned char message[len]锛屾牎椹�(y脿n)纰肩偤锛� unsigned short code = do_crc锛坢essage, len锛�; 骞朵笖鎸変互涓嬫柟寮忕櫦(f膩)閫佸嚭鍘伙細 message[len] = code & 0x00ff; message[len + 1] = 锛坈ode >> 8锛� & 0x00ff; 鎺ユ敹绔皪(du矛)鏀跺埌鐨刲en + 2瀛楃瘈(ji茅)鍩�(zh铆)琛宒o_crc锛屽鏋滄矑(m茅i)鏈夊樊閷�(cu貌)鐧�(f膩)鐢熷墖绲�(ji茅)鏋滄噳(y墨ng)鐐�0銆� 鍦ㄤ竴浜涘偝杓稿崝(xi茅)璀颁腑锛岀櫦(f膩)閫佺骞朵笉鎸囧嚭娑堟伅闀�(zh菐ng)搴︼紝鑰屾槸閲囩敤绲�(ji茅)鏉熸(bi膩o)蹇�锛岃€冩叜浠ヤ笅骞剧ó宸尟(cu貌)锛� 1锛夊湪娑堟伅涔嬪墠锛屽鍔�1鍊�(g猫)鎴栧鍊�(g猫)0瀛楃瘈(ji茅)锛� 2锛夋秷鎭互1鍊�(g猫)鎴栧鍊�(g猫)閫ｇ簩(x霉)鐨�0瀛楃瘈(ji茅)闁�(k膩i)濮�锛屼笩鎺�1鍊�(g猫)鎴栧鍊�(g猫)0锛� 3锛夊湪娑堟伅锛堝寘鎷牎椹�(y脿n)纰硷級涔嬪悗锛屽鍔�1鍊�(g猫)鎴栧鍊�(g猫)0瀛楃瘈(ji茅)锛� 4锛夋秷鎭紙鍖呮嫭鏍￠(y脿n)纰硷級浠�1鍊�(g猫)鎴栧鍊�(g猫)閫ｇ簩(x霉)鐨�0瀛楃瘈(ji茅)绲�(ji茅)灏�锛屼笩鎺�1鍊�(g猫)鎴栧鍊�(g猫)0锛� 椤劧锛岄€欏咕绋樊閷�(cu貌)閮芥娓�(c猫)涓嶅嚭渚�(l谩i)锛屽叾鍘熷洜灏辨槸濡傛灉瀵勫瓨鍣ㄥ€肩偤0锛岃檿鐞�0娑堟伅瀛楃瘈(ji茅)锛堟垨浣嶏級锛屽瘎瀛樺櫒鍊间笉璁�銆傜偤浜嗚В姹哄墠2鍊�(g猫)鍟�(w猫n)椤�锛屽彧闇€瀵勫瓨鍣ㄧ殑鍒濆€奸潪0鍗冲彲锛屽皪(du矛)do_crc浣滀互涓嬫敼閫�(j矛n)锛� unsigned short do_crc锛坲nsigned short reg_init, unsigned char 锛妋essage, unsigned int len锛� 锝� unsigned short crc_reg = reg_init; while 锛坙en鈥斺€旓級 crc_reg = 锛坈rc_reg >> 8锛� 锔� crc16_ccitt_table[锛坈rc_reg 锔� 锛妋essage++锛� & 0xff]; return crc_reg; 锝� 鍦–RC16-CCITT妯�(bi膩o)婧�(zh菙n)涓璻eg_init = 0xffff锛岀偤浜嗚В姹哄悗2鍊�(g猫)鍟�(w猫n)椤�锛屽湪CRC16-CCITT妯�(bi膩o)婧�(zh菙n)涓皣瑷�(j矛)绠楀嚭鐨勬牎椹�(y脿n)纰艰垏0xffff閫�(j矛n)琛岀暟鎴栵紝鍗筹細 unsigned short code = do_crc锛�0xffff, message, len锛�; code 锔�= 0xffff; message[len] = code & 0x00ff; message[len + 1] = 锛坈ode >> 8锛� & 0x00ff; 椤劧锛岀従(xi脿n)鍦ㄦ帴鏀剁灏�(du矛)鏀跺埌鐨勬墍鏈夊瓧绡€(ji茅)鍩�(zh铆)琛宒o_crc锛屽鏋滄矑(m茅i)鏈夊樊閷�(cu貌)鐧�(f膩)鐢熷墖绲�(ji茅)鏋滄噳(y墨ng)鐐烘煇涓€甯稿€糋OOD_CRC銆傚叾婊�(m菐n)瓒充互涓嬮棞(gu膩n)绯伙細 unsigned char p[]= 锝�0xff, 0xff锝�; GOOD_CRC = do_crc锛�0, p, 2锛�; 鍏剁祼(ji茅)鏋滅偤GOOD_CRC = 0xf0b8銆� 鍙冭€冩枃鐛�(xi脿n) 鈥斺€斺€斺€斺€斺€斺€斺€� [1] Ross N. Williams锛�"A PAINLESS GUIDE TO CRC ERROR DETECTION ALGORITHMS"锛孷ersion 3锛� http://www.ross.net/crc/crcpaper.html锛孉ugust 1993 [2] Simpson, W., Editor, "PPP in HDLC Framing"锛孯FC 1549, December 1993 [3] P. E. Boudreau锛學. C. Bergman and D. R. lrvin锛�"Performance of a cyclic redundancy check and its interaction with a data scrambler"锛孖BM J. RES. DEVELOP.锛孷OL.38 NO.6锛孨ovember 1994