def calc_crc16()

in system/ymodem/sbrb.py [0:0]


def calc_crc16(data, crc=0):
    crctable = [
        0x0000,
        0x1021,
        0x2042,
        0x3063,
        0x4084,
        0x50A5,
        0x60C6,
        0x70E7,
        0x8108,
        0x9129,
        0xA14A,
        0xB16B,
        0xC18C,
        0xD1AD,
        0xE1CE,
        0xF1EF,
        0x1231,
        0x0210,
        0x3273,
        0x2252,
        0x52B5,
        0x4294,
        0x72F7,
        0x62D6,
        0x9339,
        0x8318,
        0xB37B,
        0xA35A,
        0xD3BD,
        0xC39C,
        0xF3FF,
        0xE3DE,
        0x2462,
        0x3443,
        0x0420,
        0x1401,
        0x64E6,
        0x74C7,
        0x44A4,
        0x5485,
        0xA56A,
        0xB54B,
        0x8528,
        0x9509,
        0xE5EE,
        0xF5CF,
        0xC5AC,
        0xD58D,
        0x3653,
        0x2672,
        0x1611,
        0x0630,
        0x76D7,
        0x66F6,
        0x5695,
        0x46B4,
        0xB75B,
        0xA77A,
        0x9719,
        0x8738,
        0xF7DF,
        0xE7FE,
        0xD79D,
        0xC7BC,
        0x48C4,
        0x58E5,
        0x6886,
        0x78A7,
        0x0840,
        0x1861,
        0x2802,
        0x3823,
        0xC9CC,
        0xD9ED,
        0xE98E,
        0xF9AF,
        0x8948,
        0x9969,
        0xA90A,
        0xB92B,
        0x5AF5,
        0x4AD4,
        0x7AB7,
        0x6A96,
        0x1A71,
        0x0A50,
        0x3A33,
        0x2A12,
        0xDBFD,
        0xCBDC,
        0xFBBF,
        0xEB9E,
        0x9B79,
        0x8B58,
        0xBB3B,
        0xAB1A,
        0x6CA6,
        0x7C87,
        0x4CE4,
        0x5CC5,
        0x2C22,
        0x3C03,
        0x0C60,
        0x1C41,
        0xEDAE,
        0xFD8F,
        0xCDEC,
        0xDDCD,
        0xAD2A,
        0xBD0B,
        0x8D68,
        0x9D49,
        0x7E97,
        0x6EB6,
        0x5ED5,
        0x4EF4,
        0x3E13,
        0x2E32,
        0x1E51,
        0x0E70,
        0xFF9F,
        0xEFBE,
        0xDFDD,
        0xCFFC,
        0xBF1B,
        0xAF3A,
        0x9F59,
        0x8F78,
        0x9188,
        0x81A9,
        0xB1CA,
        0xA1EB,
        0xD10C,
        0xC12D,
        0xF14E,
        0xE16F,
        0x1080,
        0x00A1,
        0x30C2,
        0x20E3,
        0x5004,
        0x4025,
        0x7046,
        0x6067,
        0x83B9,
        0x9398,
        0xA3FB,
        0xB3DA,
        0xC33D,
        0xD31C,
        0xE37F,
        0xF35E,
        0x02B1,
        0x1290,
        0x22F3,
        0x32D2,
        0x4235,
        0x5214,
        0x6277,
        0x7256,
        0xB5EA,
        0xA5CB,
        0x95A8,
        0x8589,
        0xF56E,
        0xE54F,
        0xD52C,
        0xC50D,
        0x34E2,
        0x24C3,
        0x14A0,
        0x0481,
        0x7466,
        0x6447,
        0x5424,
        0x4405,
        0xA7DB,
        0xB7FA,
        0x8799,
        0x97B8,
        0xE75F,
        0xF77E,
        0xC71D,
        0xD73C,
        0x26D3,
        0x36F2,
        0x0691,
        0x16B0,
        0x6657,
        0x7676,
        0x4615,
        0x5634,
        0xD94C,
        0xC96D,
        0xF90E,
        0xE92F,
        0x99C8,
        0x89E9,
        0xB98A,
        0xA9AB,
        0x5844,
        0x4865,
        0x7806,
        0x6827,
        0x18C0,
        0x08E1,
        0x3882,
        0x28A3,
        0xCB7D,
        0xDB5C,
        0xEB3F,
        0xFB1E,
        0x8BF9,
        0x9BD8,
        0xABBB,
        0xBB9A,
        0x4A75,
        0x5A54,
        0x6A37,
        0x7A16,
        0x0AF1,
        0x1AD0,
        0x2AB3,
        0x3A92,
        0xFD2E,
        0xED0F,
        0xDD6C,
        0xCD4D,
        0xBDAA,
        0xAD8B,
        0x9DE8,
        0x8DC9,
        0x7C26,
        0x6C07,
        0x5C64,
        0x4C45,
        0x3CA2,
        0x2C83,
        0x1CE0,
        0x0CC1,
        0xEF1F,
        0xFF3E,
        0xCF5D,
        0xDF7C,
        0xAF9B,
        0xBFBA,
        0x8FD9,
        0x9FF8,
        0x6E17,
        0x7E36,
        0x4E55,
        0x5E74,
        0x2E93,
        0x3EB2,
        0x0ED1,
        0x1EF0,
    ]

    crc = 0x0
    for char in bytearray(data):
        crctbl_idx = ((crc >> 8) ^ char) & 0xFF
        crc = ((crc << 8) ^ crctable[crctbl_idx]) & 0xFFFF
    return crc & 0xFFFF