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1 | //----------------------------------------------------------------------------- |
2 | // This code is licensed to you under the terms of the GNU GPL, version 2 or, |
3 | // at your option, any later version. See the LICENSE.txt file for the text of |
4 | // the license. |
5 | //----------------------------------------------------------------------------- |
6 | // CRC16 |
7 | //----------------------------------------------------------------------------- |
8 | |
fdcc61d3 |
9 | #include "crc16.h" |
10 | |
11 | unsigned short update_crc16( unsigned short crc, unsigned char c ) |
12 | { |
13 | unsigned short i, v, tcrc = 0; |
14 | |
15 | v = (crc ^ c) & 0xff; |
16 | for (i = 0; i < 8; i++) { |
17 | tcrc = ( (tcrc ^ v) & 1 ) ? ( tcrc >> 1 ) ^ 0x8408 : tcrc >> 1; |
18 | v >>= 1; |
19 | } |
20 | |
21 | return ((crc >> 8) ^ tcrc)&0xffff; |
22 | } |