97:, known locally as 'bastardized octal'. It represented 8 bits with three octal digits but the first digit represented only the two most-significant bits (with values 0..3), whilst the others the remaining two groups of three bits (with values 0..7) each. A more polite colloquial name was 'silly octal', derived from the official name which was
833:
to do the conversion, just put a zero between the two bytes, e.g. A9oC2 hex. Conversion to octal gives 251o302, the split octal value (with "o" als the digit zero to separate the two bytes). Same works for octal to hex. 377o377 octal to hex gives FFoFF Also usable on other machines with base
134:
Following this convention, 16-bit addresses were split into two 8-bit numbers printed separately in octal, that is base 8 on 8-bit boundaries: the first memory location was "000.000" and the memory location after "000.377" was "001.000" (rather than "000.400").
390:(NB. This is an edited version of a talk given to North West Group of the Society at the Museum of Science and Industry, Manchester, UK on 1996-10-01. It mentions the term "slob" and "slob-octal" as equivalent to "syllabic octal".)
138:
In order to distinguish numbers in split-octal notation from ordinary 16-bit octal numbers, the two digit groups were often separated by a slash (/), dot (.), colon (:), comma (,), hyphen (-), or hash mark (#).
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board, the front-panel keyboard got a new set of labels and hexadecimal notation was used instead of octal.
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266:(348 pages) (NB. The author confuses the 16-bit split octal with the 8-bit syllabic octal notation.)
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442:"As I recall some DEC utilities supported 'split octal' which was base 8 on 8 bit boundaries"
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669:. dp Series in Software. Vol. 3 (1 ed.). Portland, Oregon, USA: Dilithium Press.
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with
Advantage ROM. It works because 3 hex digits are 12 bits, exactly 4 oct digits.
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This 8-bit notation was similar to the later 16-bit split octal notation.
839:
127:
in the late 1970s (and sometimes up to the present). It was also used by
116:
847:
843:
835:
830:
739:"A8008 8008 (1975) cross-assembler A8008 8008 (1975) cross-assembler"
166:
615:
The 8080/Z-80 Assembly
Language: Techniques for Improved Programming
255:
94:
230:
Introduction to 80x86 Assembly
Language and Computer Architecture
83:, it was not yet well known, and English Electric used the word '
636:
120:
72:
472:
Control Data 8092 TeleProgrammer: Programming
Reference Manual
80:
150:
used either straight octal (where 377 is followed by 400) or
528:
pp. 30, 32, 34, 36, 38–40, 42–43, 156–158, 160–161 .
524:. Vol. 2, no. 9. Glastonbury, Connecticut, USA:
575:. Vol. 4, no. 3. Nashua, New Hampshire, USA:
180:
can implicitly support numbers in split octal as well.
512:"Control the World! (Or at Least a Few Analog Points)"
401:"Architecture of the English Electric KDF9 computer"
304:(10 pages) (NB. Mentions the term "syllabic octal".)
358:- The Bulletin of the Computer Conservation Society
336:(8 pages) (NB. Mentions the term "syllabic octal".)
765:"{31} Binary, Decimal Octal, Split Octal, and HEX"
101:(also known as 'slob-octal' or 'slob' notation,).
45:, respectively, used in some historical contexts.
579:pp. 12–13, 124–130, 132–134, 136–138, 140 .
882:"Split Octal (was RE: 8080 Trainer - more info)"
808:Roland57; Garnier, Jean François (2021-12-02) .
667:8080 Machine Language Programming for Beginners
41:are two similar notations for 8-bit and 16-bit
232:(3 ed.). Burlington, Massachusetts, USA:
154:. With the introduction of the optional HA8-6
8:
226:"Chapter 7.2. Shift and Rotate Instructions"
861:: CS1 maint: numeric names: authors list (
75:' had been coined by the designers of the
737:Johnson, Herbert "Herb" R. (2019-10-02).
702:Belt, Forest. "39. Split-Octal Concept".
711:. Computer Diagnostics. pp. 48–50.
216:
115:is an unusual address notation used by
854:
7:
814:The Museum of HP Calculators (MoHPC)
165:Through tricky number alignment the
93:programming used an unusual form of
689:000,376 000,377 001,000 001,001
829:Before you write a program on the
234:Jones & Bartlett Learning, LLC
25:
810:"hp16 and split octal conversion"
410:(CCS). September 2009. CCS-N4X2.
348:"The KDF9 Computer — 30 Years On"
87:' for what is now called a byte.
563:"Building the Heath H8 Computer"
911:from the original on 2023-10-16
888:from the original on 2023-10-16
820:from the original on 2022-07-17
745:from the original on 2020-02-07
718:from the original on 2020-07-31
594:from the original on 2020-07-08
561:Poduska, Paul R. (March 1979).
543:from the original on 2019-07-20
489:from the original on 2020-05-25
478:. Minneapolis, Minnesota, USA:
452:from the original on 2020-07-27
427:
417:from the original on 2020-04-04
379:from the original on 2020-07-27
327:from the original on 2023-10-16
295:from the original on 2020-07-27
705:Introduction to number systems
158:processor replacement for the
1:
789:Wallace, Dave (2011-07-23) .
618:(1 ed.). New York, USA:
440:McManis, Chuck (2016-12-09).
408:Computer Conservation Society
362:Computer Conservation Society
129:Digital Equipment Corporation
880:Peacock, Jack (1998-04-22).
426:(NB. Refers to Beard's 1997
288:. c. 1960s. pp. 40–49.
224:Detmer, Richard C. (2015) .
620:John Wiley & Sons, Inc.
573:– the small systems journal
522:– the small systems journal
346:Beard, Bob (Autumn 1997) .
959:
943:Positional numeral systems
68:machine in the mid-1960s.
64:in conjunction with their
26:
612:Miller, Alan R. (1981) .
205:Segment:offset addressing
639:. ark:/13960/t4zg8792b.
480:Control Data Corporation
119:'s PAM8 and portions of
27:Not to be confused with
834:conversion such as the
791:"H-8 Technical details"
763:Andrews, Craig (2020).
446:Hacker News: Combinator
364:(CCS). pp. 7–15 .
238:Ascend Learning Company
176:calculators supporting
769:Bits Of The Golden Age
577:BYTE Publications Inc.
526:BYTE Publications Inc.
665:Santore, Ron (1978).
240:. pp. 223–233 .
79:for a group of eight
58:number representation
933:Early microcomputers
901:"Giving octal a try"
284:(Flowchart). KDF 8.
771:(Educational video)
71:Although the word '
655:(1+x+319+2 pages)
510:(September 1977).
482:. 1964. IDP 107a.
56:is an 8-bit octal
938:Binary arithmetic
645:978-0-471-08124-1
278:Director - Manual
247:978-1-284-03612-1
60:that was used by
16:(Redirected from
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99:syllabic octal
54:Syllabic octal
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913:. Retrieved
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890:. Retrieved
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795:the original
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676:0-91839814-2
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381:. Retrieved
356:Resurrection
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195:DEC RADIX 50
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91:Machine code
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905:AltairClone
692:(112 pages)
200:Squawk code
152:hexadecimal
125:Heathkit H8
113:Split octal
108:Split octal
39:split octal
18:Slob (KDF9)
927:Categories
915:2023-10-16
892:2023-10-16
824:2022-07-17
775:2022-07-17
749:2020-07-31
722:2020-07-31
650:2022-07-17
598:2020-07-31
547:2020-07-31
493:2020-07-27
456:2022-07-17
421:2020-07-27
383:2020-07-27
331:2023-10-16
299:2020-07-27
261:2023-10-17
256:2013034084
211:References
190:IBM SQUOZE
169:and other
585:0360-5280
534:0360-5280
370:0958-7403
909:Archived
907:. 2019.
886:Archived
857:cite web
818:Archived
743:Archived
713:Archived
637:80-21492
589:Archived
538:Archived
484:Archived
450:Archived
412:Archived
374:Archived
322:Archived
290:Archived
184:See also
123:for the
117:Heathkit
85:syllable
846:or the
428:article
131:(DEC).
842:, the
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167:HP-16C
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325:(PDF)
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293:(PDF)
282:(PDF)
142:Most
95:octal
863:link
831:hp16
681:ISBN
671:ISBN
641:ISBN
633:LCCN
623:ISBN
581:ISSN
571:BYTE
530:ISSN
520:BYTE
366:ISSN
252:LCCN
242:ISBN
160:8080
146:and
121:HDOS
81:bits
73:byte
66:KDF9
37:and
848:41C
844:42S
840:SII
836:32S
174:RPN
156:Z80
929::
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