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Lecture 6. Excess Notation. Excess Notation. Excess 8 notation indicates that the value for zero is the bit pattern for 8, that is 1000 The bit patterns are 4 bits long Positive numbers are above it in order and negative numbers are below it in order. .
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Lecture 6 Excess Notation
Excess Notation Excess 8 notation indicates that the value for zero is the bit pattern for 8, that is 1000 The bit patterns are 4 bits long Positive numbers are above it in order and negative numbers are below it in order.
Excess Notation (continue) That is the zero point for Excess 128 notation is 128; the zero point for excess 64 notation is 64; and so forth. For example, let's say we want to determine the pattern for 15 in Excess 128 notation. The decimal number would be 128 + 15, or 143. Therefore, the bit pattern would be 10001111.
Example1 A computer stores decimal integer values in 8 bits, using excess-128 notation. How would the decimal value -60 stored? Solution: stored number = -60 + 128 = 6810 (10001002)
Example 2 The binary number, 0101 1101, is in excess-128 notation. What is the number in decimal? Solution: 0101 1101 = 0*128 + 64 + 0*32 + 16 +8 + 4 + 0*2 + 1 = 93 in excess-128 actual number = 93 – 128 = -35