These number representations are used for the Control Data 1604 computer.
Floating point numbers are represented by one bit for the sign (S), 11
bits for the exponent, and 36 bits for the fraction. The exponent
is to the base 2, and has a bias of 1024. Negative numbers are
in ones complement, which means that negative exponents have a bias of
1023. This is because in ones complement there are two zeroes, +0
(all bits are zero) and -0 (all bits are 1).
SINGLE PRECISION is shown below:
| CDC 1604 48-Bit Floating Point Format | |||||||||||||||||||||||||||||||||||||||||||||||
| S | Exponent | Fraction | |||||||||||||||||||||||||||||||||||||||||||||
| 1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
17 |
18 |
19 |
20 |
21 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
29 |
30 |
31 |
32 |
33 |
34 |
35 |
36 |
37 |
38 |
39 |
40 |
41 |
42 |
43 |
44 |
45 |
46 |
47 |
48 |
DOUBLE PRECISION - None.
INTEGER numbers are 48 bits long; negative numbers are in one's complement.