Question: A computer uses an 8-bit floating-point representation consistent with IEEE 754 normalized format. It is identical to the 32-bit and 64-bit formats in terms of
A computer uses an 8-bit floating-point representation consistent with IEEE 754 normalized format. It is identical to the 32-bit and 64-bit formats in terms of the meaning of fields and special encodings. The format includes 1 sign bit, 4 exponent bits, and 3 mantissa (magnitude or fraction) bits. As in IEEE 754, 0000 and 1111 in exponent field are reserved.The exponent field employs an excess-7 coding.
The following table gives the 8-bit Excess-7 representation.
| Decimal | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| Unsigned | 0000 | 0001 | 0010 | 0011 | 0100 | 0101 | 0110 | 0111 |
| Excess-7 | Reserved | -6 | -5 | -4 | -3 | -2 | -1 | 0 |
| Decimal | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
| Unsigned | 1000 | 1001 | 1010 | 1011 | 1100 | 1101 | 1110 | 1111 |
| Excess-7 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | reserved |
|
|
|
|
|
[Help: in normal binary representation 240 = 111100002 = 1.111 * 27 and 15.5 = 1111.12 = 1.1111 * 23]
|
|
|
If x = 235 (235 = 111010112), how x will be represented in this scheme? Assume, if a number cannot be represented in this scheme, the next nearest possible representation will be used.
11111111 (=155), because 238 will overflow
01101111 (= 15.5), because 238 will overflow
01110111(=240), because 235 = 1.1101011 * 27, and only 3 digits are allowed in fraction. The next nearest number with only 3 digit fraction is 1.111 * 27 =240.
01101111 (=120), because 235 = 1.1101011 * 27, and only 3 digits are allowed in fraction. The possible representation is 1.111 * 26 =224.
|
|
|
|
How 2.25 will be represented?
2.25 = 1.001 * 21 = 01000001
2.25 = 10.01 * 20 = 00111010
2.25 = 1.001 * 2-1 = 00110001
2.25 = 1001 * 2-2 , it cannot be represented
How -5.5 will be represented?
-5.5 = -101.1 * 20 = 11000001
-5.5 = -1.011 * 22 = 11001011
-5.5 = -1.011 * 2-2 = 00101011
-5.5 = -1011 * 2-3 , it cannot be represented
What is(are) Zero(s) in this representation?
There are no zeros
Only one zero, 00000000
Only one zero, 10000000
There are two zeroes, 00000000 and 1000000
If x = 0/0 [assume x will be NaN], which of the following will be a possible representation for x?
01111000
11111000
01111001
00001000
If x = 1/0 [assume x will be +infinity], how x will be represented?
01111000
11111000
01111001
00001000
Step by Step Solution
There are 3 Steps involved in it
Get step-by-step solutions from verified subject matter experts
