CC2530 ADC问题

数据手册上 ADCH  ADC高位部分是[13:6]  ADCL ADC地位部分是 [5：0]，而swrc135b.ZIP 有以下程序

int16 adcSampleSingle(uint8 reference, uint8 resolution, uint8 channel)
{
    int16 value;

    ADC_ENABLE_CHANNEL(channel);

    ADCIF = 0;
    ADC_SINGLE_CONVERSION(reference | resolution | channel);
    while(!ADCIF);

    value  = (ADCH << 8) & 0xff00;
    value |= ADCL;

    ADC_DISABLE_CHANNEL(channel);

    //  The variable 'value' contains 16 bits where
    //     bit 15 is a sign bit
    //     bit [14 .. 0] contain the absolute sample value
    //     Only the r upper bits are significant, where r is the resolution
    //     Resolution:
    //        12   -> [14 .. 3] (bitmask 0x7FF8)
    //        10   -> [14 .. 5] (bitmask 0x7FE0)
    //         9   -> [14 .. 6] (bitmask 0x7FC0)
    //         7   -> [14 .. 8] (bitmask 0x7F00)

    return value;
}

是不是数据手册出现错误？