Floating Point Support

When entering data in:

Single precision

Double precision

Extended precision

Packed decimal format

the following rules must be observed:

1.The sign field is the first field and is a binary field.

2.The exponent field is the second field and is a hexadecimal field.

3.The mantissa field is the last field and is a hexadecimal field.

4.The sign field, the exponent field, and at least the first digit of the mantissa field must be present (any unspecified digits in the mantissa field are set to zero).

5.Each field must be separated from adjacent fields by an underscore.

6.All the digit positions in the sign and exponent fields must be present.

Single Precision Real

This format would appear in memory as:

1-bit sign Þeld

(1 binary digit)

 

 

8-bit biased exponent Þeld

(2 hex digits. Bias = $7F)

 

 

23-bit fraction Þeld

(6 hex digits)

 

 

A single precision number requires 4 bytes in memory.

B

B-45

Page 125
Image 125
Motorola MVME177 manual Single Precision Real, This format would appear in memory as