3.2: Unsigned and Signed Addition
- Page ID
- 19870
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As previously noted, the unsigned and signed representations may provide different interpretations for the final value being represented. However, the addition and subtraction operations are the same. For example:
| 241 | 11110001 |
| + 7 | 00000111 |
| 248 | 11111000 |
| 248 = | F8 |
| -15 | 11110001 |
| + 7 | 00000111 |
| -8 | 11111000 |
| -8 = | F8 |
The final result of 0xF8 may be interpreted as 248 for unsigned representation and -8 for a signed representation. Additionally, 0x\(F8_{16}\) is the \(^{\circ}\) (degree symbol) in the ASCII table.
As such, it is very important to have a clear definition of the sizes (byte, halfword, word, etc.) and types (signed, unsigned) of data for the operations being performed.