Difference between revisions of "Word"

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'''Word''' is the fundamental data unit of a [[computer]]. The [[ND-100|NORD-10/ND-100]] word size is 16 (sixteen) [[bit|bits]]. The [[ND-500|ND-500/ND-5000]] word size is 32 bits and a 16-bit unit is called a half-word.
 
'''Word''' is the fundamental data unit of a [[computer]]. The [[ND-100|NORD-10/ND-100]] word size is 16 (sixteen) [[bit|bits]]. The [[ND-500|ND-500/ND-5000]] word size is 32 bits and a 16-bit unit is called a half-word.
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The ND-100 has a 16-bit word format. The bits are conventionally numbered 0 to 15 from right to left. The most significant bit is number 15. The ND-500 has a 32-bit format. A 16-bit word consists of two bytes of 8 bits each. The contents of an ND-100 word is conventionally represented by a 6-digit octal number. The representation of a negative number is in the 2's complement range -32768 > x > 32767. Thus, the word with all 16 bits set to zero is 000000 (octal), while the word with all bits set to one, ie., -1, is represented as 177777 (octal)<ref>{{ND-doc|30.003.06}} Appendix A - Glossary</ref>.
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==References==
 
==References==
 
*{{ND-doc|06.026.01}}, from Glossary
 
*{{ND-doc|06.026.01}}, from Glossary
 
*{{ND-doc|05.009.03}}, from Preface
 
*{{ND-doc|05.009.03}}, from Preface
 
[[Category:Glossary]]
 
[[Category:Glossary]]

Latest revision as of 12:36, 21 May 2020

Word is the fundamental data unit of a computer. The NORD-10/ND-100 word size is 16 (sixteen) bits. The ND-500/ND-5000 word size is 32 bits and a 16-bit unit is called a half-word.

The ND-100 has a 16-bit word format. The bits are conventionally numbered 0 to 15 from right to left. The most significant bit is number 15. The ND-500 has a 32-bit format. A 16-bit word consists of two bytes of 8 bits each. The contents of an ND-100 word is conventionally represented by a 6-digit octal number. The representation of a negative number is in the 2's complement range -32768 > x > 32767. Thus, the word with all 16 bits set to zero is 000000 (octal), while the word with all bits set to one, ie., -1, is represented as 177777 (octal)[1].

References

  • Norsk Data Document ND–30.003.06 SINTRAN III System Supervisor Appendix A - Glossary