Solartron Mobrey 3595 4C, Руководство пользователя

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3595 4C User Manual Part Two Results and Error Formats
35952350 (CH02/AA)
2-5
2.3 FOUR-BYTE RESULT FORMAT
Analogue and digital data are sent in a 4-byte result format that closely resembles the IEEE 754 format.
The 4-byte format differs from IEEE 754 in having a shorter mantissa, that is 17 bits rather than 23. Four of
the six bits are thus freed and are used to hold information on the significance of the result, as follows:
S e
7
...... e
1
First Byte
m
22
..... m
16
e
0
m
15
..... m
8
m
1
m
0
00S
4
S
3
S
2
S
1
Fourth Byte
Sign bit (most significant bit of first byte)
Binary exponent with excess of 127
(e
7
= most significant)
Implied 1. of mantissa
Fractional part of mantissa
(m
22
= most significant)
Significance
The significance is the number of valid decimal places in the result. This is decided by the range selected
in the IMP.