如何解释DS1854，DS1857和DS1858温度和电压读

62h (VCC MSB)								63h (VCC LSB)
215	214	213	212	211	210	29	28	27	26	25	24	23	22	21	20
215	214	213	212	211	210	29	28	27	26	25	24	0	0	0	0

As an example, the values read from 62h and 63h are found to be D7A0h. Translating this number into a decimal results in a value of 55200. Multiplying this value by the scaling factor of 100μV results in the scaled voltage value of 5.520V.

Monitored Analog Input (MON) Translations

The analog input pins MON1, MON2, and in the case of the DS1858, MON3 are unsigned 16-bit numbers, and are translated using a method similar to the VCC translation. As with the VCC translation, the lower 4 bits are masked with 0's because the resolution attained using those bits would produce inaccurate voltage values since those values would be below the noise floor of the converter. Table 5 shows the bit weights of the analog input bytes and the masking of the 4 lower bits. With the lower 4 bits masked, the maximum range is 65520, which translates to a voltage range of 0V to 2.499V when it is multiplied by the scaling factor of 38.147μV.

Table 5. Monitored analog input bit weights and masking

64h (MON1 MSB)								65h (MON1 LSB)
66h (MON2 MSB)								67h (MON2 LSB)
68h (MON3 MSB, DS1858 only)								69h (MON3 LSB, DS1858 only)
215	214	213	212	211	210	29	28	27	26	25	24	23	22	21	20
215	214	213	212	211	210	29	28	27	26	25	24	0	0	0	0

As an example, the hex value of 9E70h is read from the two address locations. After masking the 4 lower bits with 0's, the binary value is determined to be 1001 1110 0111 0000. The decimal equivalent is 40560. Multiplying this value by the scaling factor of 38.147μV results in the scaled voltage value of 1.547V.