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Compaq 164SX User Manual

Page 12

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Note

Notes emphasize particularly important information.

Numbering

All numbers are decimal or hexadecimal unless otherwise indicated. The prefix 0x
indicates a hexadecimal number. For example, 19 is decimal, but 0x19 and 0x19A
are hexadecimal (also see Addresses). Otherwise, the base is indicated by a sub-
script; for example, 100

2

is a binary number.

Ranges and Extents

Ranges are specified by a pair of numbers separated by two periods (..) and are inclu-
sive. For example, a range of integers 0..4 includes the integers 0, 1, 2, 3, and 4.

Extents are specified by a pair of numbers in brackets ([]) separated by a colon (:)
and are inclusive. Bit fields are often specified as extents. For example, bits [7:3]
specifies bits 7, 6, 5, 4, and 3.

Register and Memory Figures

Register figures have bit and field position numbering starting at the right (low
order) and increasing to the left (high order).

Memory figures have addresses starting at the top and increasing toward the bottom.

Quadword

4

8

64

2 Longwords

Octaword

8

16

128

2 Quadwords

Hexword

16

32

256

2 Octawords

Term Words

Bytes

Bits

Other