Talk:XENIX - Revision history

Jnc: /* PDP-11 versions */ Fix formatting, add sig

2024-10-10T21:12:38Z

‎PDP-11 versions: Fix formatting, add sig

ForOldHack: /* PDP-11 versions */ There is NO DEC LSI-11 System, only CPU card.

2024-10-03T22:05:32Z

‎PDP-11 versions: There is NO DEC LSI-11 System, only CPU card.

Jnc: /* PDP-11 versions */ fmt

2024-07-22T03:14:50Z

‎PDP-11 versions: fmt

Jnc: /* PDP-11 versions */ Try finding 'LSI-11/34'in ''any'' DEC document - one can't.

2024-07-20T16:50:34Z

‎PDP-11 versions: Try finding 'LSI-11/34'in ''any'' DEC document - one can't.

Jnc: Fix formatting

2024-07-20T16:37:35Z

Fix formatting

ForOldHack: /* some more sources for rewrite of article. */

2024-07-19T22:56:24Z

‎some more sources for rewrite of article.

Jnc: /* PDP-11 versions */ new section

2024-07-18T21:15:43Z

‎PDP-11 versions: new section

Jnc: Format so lists are readable

2024-07-18T21:04:47Z

Format so lists are readable

Jnc: /* The documented history of Xenix-11, Xenix-1, Xenix-3, and SCO System V, Xenix 386, 286 and 8086. */ More careful response

2023-10-23T04:31:49Z

‎The documented history of Xenix-11, Xenix-1, Xenix-3, and SCO System V, Xenix 386, 286 and 8086.: More careful response

Jnc: /* The documented history of Xenix-11, Xenix-1, Xenix-3, and SCO System V, Xenix 386, 286 and 8086. */ byte ordering

2023-10-22T22:55:23Z

‎The documented history of Xenix-11, Xenix-1, Xenix-3, and SCO System V, Xenix 386, 286 and 8086.: byte ordering

@@ Line 260: / Line 260: @@
 :: I know all about the various PDP-11's; I worked very extensively with all of them.
-:: The point is that there is ''no such thing'' as a "LSI-11/34". {fact checked as weird - due to MS Marketing}
+:: The point is that there is ''no such thing'' as a "LSI-11/34".
-:: Almost everything with 'LSI-11' CPU's is QBUS (with the exception of the [[PDP-11/24]] - {fact checked as true}
+:: Almost everything with 'LSI-11' CPU's is QBUS (with the exception of the [[PDP-11/24]] - and it uses the [[F-11 chip set]], so it's technically not an LSI-11 anyway); the -11/34 is a UNIBUS machine (and it uses a bespoke CPU, the [[KD11-E CPU]], which is not shared with any other machine).
 :: Try finding "LSI-11/34" in ''any'' DEC document - one can't. ''It does not exist''. [[User:Jnc|Jnc]] ([[User talk:Jnc|talk]]) 18:49, 20 July 2024 (CEST)
-::Yes, I quite agree, and disagree.
+:::* The point is that there is ''no such thing'' as a "LSI-11/34". {fact checked as weird - due to MS Marketing}
-::DEC Never sold a LSI-11 computer. They sold a PDP-11/03 with a Western Digital LSI-11 processor in it,
+:::* Almost everything with 'LSI-11' CPU's is QBUS (with the exception of the [[PDP-11/24]] - {fact checked as true}
-:: the LSI-11/34 is NOT a DEC product, its a Microsoft labeled machine.
+:::* the -11/34 is a UNIBUS machine (and it uses a bespoke CPU, the [[KD11-E CPU]], which is not shared with any other machine). {fact checked as true}
 :: "This PDP-11/23 was originally a PDP-11/03, but it was upgraded with the 11/23 CPU module."
-:: It is unknown at this time, whether they upgraded the LSI-11 with a 11/23 or what happened,
+::: Yes, I quite agree, and disagree.
-:: BUT you can pretty much guarantee that it had little to do with DEC, and all to do with Microsoft's random directions.
+::: DEC Never sold a LSI-11 computer. They sold a PDP-11/03 with a Western Digital LSI-11 processor in it,
-:: The source of this information is the picture, and the head of MS Marketing for Xenix, which it means lies like a ambulance chasing lawyer.
+::: the LSI-11/34 is NOT a DEC product, its a Microsoft labeled machine.
-:: But there is the name, Western Digital Sold PDP-11/03s as their machine the LSI-11/03, but the real problem,
+::: "This PDP-11/23 was originally a PDP-11/03, but it was upgraded with the 11/23 CPU module."
-:: In the photo of Bill Gates, I cannot make out the name on the Machine if its a DEC PDP-11/03 or the Western Digital Branded 11/03-LSI-11. ( The name plate was removed )
+::: It is unknown at this time, whether they upgraded the LSI-11 with a 11/23 or what happened,
-:: I was not there, but I have a picture, and videos.
+::: BUT you can pretty much guarantee that it had little to do with DEC, and all to do with Microsoft's random directions.
-:: And of the PDP-11/34, there is a video. Its a Microsoft guy, and I am going to tell you what I think of Microsoft guys: Untrustworthy.
+::: The source of this information is the picture, and the head of MS Marketing for Xenix, which it means lies like a ambulance chasing lawyer.
-:: https://www.youtube.com/watch?v=XT6t2L3SVM8&t=2s
+::: But there is the name, Western Digital Sold PDP-11/03s as their machine the LSI-11/03, but the real problem,
 == Some errors but we have a lot more actual dates ==

@@ Line 260: / Line 260: @@
 :: I know all about the various PDP-11's; I worked very extensively with all of them.
-:: The point is that there is ''no such thing'' as a "LSI-11/34".
+:: The point is that there is ''no such thing'' as a "LSI-11/34". {fact checked as weird - due to MS Marketing}
-:: Almost everything with 'LSI-11' CPU's is QBUS (with the exception of the [[PDP-11/24]] - and it uses the [[F-11 chip set]], so it's technically not an LSI-11 anyway); the -11/34 is a UNIBUS machine (and it uses a bespoke CPU, the [[KD11-E CPU]], which is not shared with any other machine).
+:: Almost everything with 'LSI-11' CPU's is QBUS (with the exception of the [[PDP-11/24]] - {fact checked as true}
 :: Try finding "LSI-11/34" in ''any'' DEC document - one can't. ''It does not exist''. [[User:Jnc|Jnc]] ([[User talk:Jnc|talk]]) 18:49, 20 July 2024 (CEST)
 == Some errors but we have a lot more actual dates ==

@@ Line 262: / Line 262: @@
 :: The point is that there is ''no such thing'' as a "LSI-11/34".
 :: Almost everything with 'LSI-11' CPU's is QBUS (with the exception of the [[PDP-11/24]] - and it uses the [[F-11 chip set]], so it's technically not an LSI-11 anyway); the -11/34 is a UNIBUS machine (and it uses a bespoke CPU, the [[KD11-E CPU]], which is not shared with any other machine).
-:: Try finding 'LSI-11/34'in ''any'' DEC document - one can't. ''It does not exist''. [[User:Jnc|Jnc]] ([[User talk:Jnc|talk]]) 18:49, 20 July 2024 (CEST)
+:: Try finding "LSI-11/34" in ''any'' DEC document - one can't. ''It does not exist''. [[User:Jnc|Jnc]] ([[User talk:Jnc|talk]]) 18:49, 20 July 2024 (CEST)
 == Some errors but we have a lot more actual dates ==

@@ Line 258: / Line 258: @@
 : and then... Microsoft ran it on VAX-11/780. All of this is internal use only so its all based on historical posts,
 : and not the analysis of data graveyards. [[User:ForOldHack|ForOldHack]] ([[User talk:ForOldHack|ForOldHack]]) 22:56, 19 July 2024
 == Some errors but we have a lot more actual dates ==

@@ Line 88: / Line 88: @@
   Man Pages
   Games			2.2.2		grep "^#rel=" /etc/perms/games
   Fox (dbase 2 clone)
   MSBASIC			5.41		Appears on startup screen.
   MultiPlan		3.00N
@@ Line 95: / Line 94: @@
 == XENIX 386 ONLY ==
 SCO Xenix 386		2.3.4		uname -X | grep -y "rel"
-Tandy Xenix 386
+ SCO Xenix 386		2.3.4		uname -X | grep -y "rel"
-Unisys Xenix 386
+ Tandy Xenix 386
-DevSys 386		2.3.0		grep "^#rel=" /etc/perms/devsys
+ Unisys Xenix 386
-Text Processing Sys
+ DevSys 386		2.3.0		grep "^#rel=" /etc/perms/devsys
-Man Pages		2.2.0 ????	grep "^#rel=" /etc/perms/man
+ Text Processing Sys
-Games
+ Man Pages		2.2.0 ????	grep "^#rel=" /etc/perms/man
-TCP/IP			1.2.0		grep "^#rel=" /etc/perms/tcprt
+ Games
-Streams runtime		1.0.0c		grep "^#rel=" /etc/perms/streamsrt
+ TCP/IP			1.2.0		grep "^#rel=" /etc/perms/tcprt
-Xenix-Net
+ Streams runtime		1.0.0c		grep "^#rel=" /etc/perms/streamsrt
-UniPATH SNA-3270
+ Xenix-Net
-Xsight for Xenix	2.0.0
+ UniPATH SNA-3270
-Xsight for DOS		2.0.0
+ Xsight for Xenix	2.0.0
-Xsight 386 complete	5.0.0
+ Xsight for DOS		2.0.0
-SCO Office Portfolio	2.0.1
+ Xsight 386 complete	5.0.0
-SCO Manager		2.1
+ SCO Office Portfolio	2.0.1
-Multiview Runtime	1.6 ????
+ SCO Manager		2.1
-SCO Professional	2.1		grep "^#rel=" /etc/perms/pro
+ Multiview Runtime	1.6 ????
-SCO Lyrix		6.1
+ SCO Professional	2.1		grep "^#rel=" /etc/perms/pro
-Integra			1.1.1
+ SCO Lyrix		6.1
-Foxbase+		2.1.2		Appears on startup screen.
+ Integra			1.1.1
-HCR/SCO C++		3.0.0
+ Foxbase+		2.1.2		Appears on startup screen.
-SCO C++			3.1.0
+ HCR/SCO C++		3.0.0
-SCO Accell
+ SCO C++			3.1.0
-VP/IX			1.2.0		grep "^#rel=" /etc/perms/vpix
+ SCO Accell
-MS Word			3.0
+ VP/IX			1.2.0		grep "^#rel=" /etc/perms/vpix
-ImageBuilder
+ MS Word			3.0
-MasterPlan
+ ImageBuilder
-Statistician
+ MasterPlan
-Eroff			3.0
+ Statistician
-MS C			3.0
+ Eroff			3.0
-MS Basic Interpreter	5.41		Appears on startup.
+ MS C			3.0
-MS Basic Compiler
+ MS Basic Interpreter	5.41		Appears on startup.
-MS Pascal Compiler
+ MS Basic Compiler
-MS Fortran Compiler	3.0
+ MS Pascal Compiler
-LPI-Fortran		3.20.00
+ MS Fortran Compiler	3.0
-LPI-Basic
+ LPI-Fortran		3.20.00
-LPI-Cobol
+ LPI-Basic
-LPI-Pascal
+ LPI-Cobol
-LPI-PL/I
+ LPI-Pascal
-LPI-RPG II
+ LPI-PL/I
-LPI-Debug
+ LPI-RPG II
-SCO PHIGS		1.0.0
+ LPI-Debug
 == UNIX (ODT) ONLY SCO Open Desktop ==
   SCO Unix		3.2v4.2		uname -X | grep -y "rel"
   TCP/IP			1.2.1
@@ Line 152: / Line 153: @@
 === Third Party ===
   JTAPE for Xenix 386     2.55   grep "^#rel=" /etc/perms/jt
   JTAPE for Unix 3.2      2.6    grep "^#rel=" /etc/perms/jt
@@ Line 246: / Line 248: @@
 The list entry "ran on a LSI-11/34" is confused; there is no such thing as an "LSI-11/34". This might refer to a [[PDP-11/34]] (which IIRC was used at one point for XENIX work at uSloth) or a [[PDP-11/23]], which is ''almost'' identical, programming-wise, to a PDP-11/34. (To the point that it was pretty trivial to move [[V6 UNIX]] from the [[PDP-11/40]] on which it ran natively, which is also very similar to these two, to the 11-23: see [[Running UNIX V6 on an -11/23]]) [[User:Jnc|Jnc]] ([[User talk:Jnc|talk]]) 23:15, 18 July 2024 (CEST)
-The PDP-11/34 was distinct from the LSI-11/34 being of a different type of silicon.
+: The PDP-11/34 was distinct from the LSI-11/34 being of a different type of silicon.
-The LSI-11 https://gunkies.org/wiki/LSI-11
+:*[[LSI-11]]
-The CPU Cards are different. The PDP-11 uses discreet logic.
+: The CPU Cards are different. The PDP-11 uses discreet logic.
-The LSI-11 used the LSI-11 chip set. https://gunkies.org/wiki/LSI-11_chip_set
+: The LSI-11 used the [[LSI-11 chip set]].
-The history was that H** ported UNIX to the PDP-11/34, and then
+: The history was that H** ported UNIX to the PDP-11/34, and then
-gave it to Microsoft to run on a LSI-11/34: Which is in pictures of Bill Gates computer collection,
+: gave it to Microsoft to run on a LSI-11/34: Which is in pictures of Bill Gates computer collection,
-and then... Microsoft ran it on VAX-11/780. All of this is internal use only so its all based on historical posts,
+: and then... Microsoft ran it on VAX-11/780. All of this is internal use only so its all based on historical posts,
-and not the analysis of data graveyards.
+: and not the analysis of data graveyards. [[User:ForOldHack|ForOldHack]] ([[User talk:ForOldHack|ForOldHack]]) 22:56, 19 July 2024
 == Some errors but we have a lot more actual dates ==
-https://www.abortretry.fail/p/the-history-of-xenix
+[https://www.abortretry.fail/p/the-history-of-xenix The History of XENIX]
 Unix was originally created to run on mainframes, but eventually moved on to other systems. One of the first companies outside of AT&T to sell Unix was named Interactive Systems Corporation. Interactive Systems Corporation was founded by Peter G. Weiner in 1977. (Weiner was Brian Kernighan’s Ph.D. advisor. Kernighan was one of the creators of Unix.)
-ISC produced a number of Unix based products, including a port of Unix to the IBM PC named PC/IX. PC/IX was followed in 1985 by 386/ix. While PC/IX was based on UNIX System III, 386/ix was based on UNIX System V, Release 3. Later, the operating system was renamed INTERACTIVE UNIX System V/386 and rebased on UNIX System V, Release 3.2.
+ISC produced a number of Unix based products, including a port of Unix to the IBM PC named PC/IX. PC/IX was followed in 1985 by 386/ix. While PC/IX was based on UNIX System III, 386/ix was based on UNIX System V, Release 3. Later, the operating system was renamed INTERACTIVE UNIX System V/386 and rebased on UNIX System V, Release 3.2. [[User:ForOldHack|ForOldHack]] ([[User talk:ForOldHack|ForOldHack]]) 22:56, 19 July 2024

← Older revision		Revision as of 22:56, 19 July 2024
Line 245:		Line 245:

	The list entry "ran on a LSI-11/34" is confused; there is no such thing as an "LSI-11/34". This might refer to a [[PDP-11/34]] (which IIRC was used at one point for XENIX work at uSloth) or a [[PDP-11/23]], which is ''almost'' identical, programming-wise, to a PDP-11/34. (To the point that it was pretty trivial to move [[V6 UNIX]] from the [[PDP-11/40]] on which it ran natively, which is also very similar to these two, to the 11-23: see [[Running UNIX V6 on an -11/23]]) [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 23:15, 18 July 2024 (CEST)		The list entry "ran on a LSI-11/34" is confused; there is no such thing as an "LSI-11/34". This might refer to a [[PDP-11/34]] (which IIRC was used at one point for XENIX work at uSloth) or a [[PDP-11/23]], which is ''almost'' identical, programming-wise, to a PDP-11/34. (To the point that it was pretty trivial to move [[V6 UNIX]] from the [[PDP-11/40]] on which it ran natively, which is also very similar to these two, to the 11-23: see [[Running UNIX V6 on an -11/23]]) [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 23:15, 18 July 2024 (CEST)
		+
		+	The PDP-11/34 was distinct from the LSI-11/34 being of a different type of silicon.
		+	The LSI-11 https://gunkies.org/wiki/LSI-11
		+	The PDP-11/34 https://gunkies.org/wiki/PDP-11/34
		+
		+	The CPU Cards are different. The PDP-11 uses discreet logic.
		+	The LSI-11 used the LSI-11 chip set. https://gunkies.org/wiki/LSI-11_chip_set
		+
		+	The history was that H** ported UNIX to the PDP-11/34, and then
		+	gave it to Microsoft to run on a LSI-11/34: Which is in pictures of Bill Gates computer collection,
		+	and then... Microsoft ran it on VAX-11/780. All of this is internal use only so its all based on historical posts,
		+	and not the analysis of data graveyards.
		+
		+	== Some errors but we have a lot more actual dates ==
		+
		+	https://www.abortretry.fail/p/the-history-of-xenix
		+
		+	Unix was originally created to run on mainframes, but eventually moved on to other systems. One of the first companies outside of AT&T to sell Unix was named Interactive Systems Corporation. Interactive Systems Corporation was founded by Peter G. Weiner in 1977. (Weiner was Brian Kernighan’s Ph.D. advisor. Kernighan was one of the creators of Unix.)
		+
		+	ISC produced a number of Unix based products, including a port of Unix to the IBM PC named PC/IX. PC/IX was followed in 1985 by 386/ix. While PC/IX was based on UNIX System III, 386/ix was based on UNIX System V, Release 3. Later, the operating system was renamed INTERACTIVE UNIX System V/386 and rebased on UNIX System V, Release 3.2.

← Older revision		Revision as of 21:15, 18 July 2024
Line 241:		Line 241:
	: In general, ordering of bytes within words is a function of the [[instruction set architecture]]; i.e. it is built into the ''hardware'' on machines that implement that ISA. Compilers generally have ''no choice'' but to use the byte ordering that is native to the ISA.		: In general, ordering of bytes within words is a function of the [[instruction set architecture]]; i.e. it is built into the ''hardware'' on machines that implement that ISA. Compilers generally have ''no choice'' but to use the byte ordering that is native to the ISA.
	: The original C compiler for the 8086 was a bit of an exception to that; the 8086 ISA didn't support long-words ''at all'' - so in that case, the compiler writers ''did'' get to make a choice. Unfortunately, they made the wrong one - they went with the screwy PDP-11 one (which is half big-endian - for the short-words within long-words, and half little-endian - for the bytes within short-words.) [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 00:55, 23 October 2023 (CEST)		: The original C compiler for the 8086 was a bit of an exception to that; the 8086 ISA didn't support long-words ''at all'' - so in that case, the compiler writers ''did'' get to make a choice. Unfortunately, they made the wrong one - they went with the screwy PDP-11 one (which is half big-endian - for the short-words within long-words, and half little-endian - for the bytes within short-words.) [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 00:55, 23 October 2023 (CEST)
		+
		+	== PDP-11 versions ==
		+
		+	The list entry "ran on a LSI-11/34" is confused; there is no such thing as an "LSI-11/34". This might refer to a [[PDP-11/34]] (which IIRC was used at one point for XENIX work at uSloth) or a [[PDP-11/23]], which is ''almost'' identical, programming-wise, to a PDP-11/34. (To the point that it was pretty trivial to move [[V6 UNIX]] from the [[PDP-11/40]] on which it ran natively, which is also very similar to these two, to the 11-23: see [[Running UNIX V6 on an -11/23]]) [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 23:15, 18 July 2024 (CEST)

@@ Line 45: / Line 45: @@
 SCO has many ways of identifying products and displaying version information.
 Some of them actually agree.
 .  Read the disk, tape or cd label.
 .  tar tvf /dev/install | grep "#rel"
 .  swconfig
 .  grep "^#rel=" /etc/perms/*
 .  uname -a (old Xenix 286 only)
 .  uname -X | grep -y "rel" (OS only)
 I suggest:
@@ Line 77: / Line 77: @@
 == XENIX 286 ONLY ==
-Name			Last Version	Incantation
+ Name			Last Version	Incantation
-SCO Xenix 286		2.3.2		uname -a
+ SCO Xenix 286		2.3.2		uname -a
-DevSys 286		2.2.1		grep "^#rel=" /etc/perms/devsys
+ DevSys 286		2.2.1		grep "^#rel=" /etc/perms/devsys
-CGI 286					grep "^#rel=" /etc/perms/cgi
+ CGI 286					grep "^#rel=" /etc/perms/cgi
-Text Processing System			grep "^#rel=" /etc/perms/text
+ Text Processing System			grep "^#rel=" /etc/perms/text
-Eroff			2.0
+ Eroff			2.0
-VP/IX 286
+ VP/IX 286
-MultiView 286
+ MultiView 286
-Man Pages
+ Man Pages
-Games			2.2.2		grep "^#rel=" /etc/perms/games
+ Games			2.2.2		grep "^#rel=" /etc/perms/games
-Fox (dbase 2 clone)
+ Fox (dbase 2 clone)
-MSBASIC			5.41		Appears on startup screen.
+ MSBASIC			5.41		Appears on startup screen.
-MultiPlan		3.00N
+ MultiPlan		3.00N
-MS Word 		3.0
+ MS Word 		3.0
 == XENIX 386 ONLY ==
@@ Line 139: / Line 139: @@
 SCO PHIGS		1.0.0
-== UNIX (ODT) ONLY SCO Open Desktop
+== UNIX (ODT) ONLY SCO Open Desktop ==
-SCO Unix		3.2v4.2		uname -X | grep -y "rel"
+ SCO Unix		3.2v4.2		uname -X | grep -y "rel"
-TCP/IP			1.2.1
+ TCP/IP			1.2.1
-LLI 			3.4.0
+ LLI 			3.4.0
-DevSys			3.2.4.2
+ DevSys			3.2.4.2
-TCP/IP Dev Sys		1.2.1
+ TCP/IP Dev Sys		1.2.1
-Games			3.2.2
+ Games			3.2.2
-NFS Sys			1.1.1d
+ NFS Sys			1.1.1d
-NFS Dev Sys		1.1.1c
+ NFS Dev Sys		1.1.1c
-Xsight 386		4.0.0
+ Xsight 386		4.0.0
-Xsight 386 Dev		4.0.0
+ Xsight 386 Dev		4.0.0
 === Third Party ===
-JTAPE for Xenix 386     2.55   grep "^#rel=" /etc/perms/jt
+ JTAPE for Xenix 386     2.55   grep "^#rel=" /etc/perms/jt
-JTAPE for Unix 3.2      2.6    grep "^#rel=" /etc/perms/jt
+ JTAPE for Unix 3.2      2.6    grep "^#rel=" /etc/perms/jt
-(No JTAPE available for 286 or OSR5)."
+ (No JTAPE available for 286 or OSR5)."
 [[User:ForOldHack|ForOldHack]] ([[User talk:ForOldHack|ForOldHack]]) 05:20, 6 December 2020
@@ Line 183: / Line 183: @@
 in Brief:
-Platform      Release
+ Platform      Release
-PDP-11        Xenix-11. This is what the Living Computer Museum supposedly has a tape of, and that someone got from HCR a few days earlier.
+ PDP-11        Xenix-11. This is what the Living Computer Museum supposedly has a tape of, and that someone got from HCR a few days earlier.
 * Intel    Xenix-1.0 This is what Microsoft shipped in Oct 1984, (c) 1984, only to have an IBM Deal announced two months later.
-M68000        Xenix-3   This was the most popular Xenix version with Radio Shacks TRS 80IIb.
+ M68000        Xenix-3   This was the most popular Xenix version with Radio Shacks TRS 80IIb.
 , 86       SCO System V
-, 386,
+, 386, Microchannel  SCO System V.2
-** This is the skeleton of the article re-write **
+ ** This is the skeleton of the article re-write **
 If this seems confusing? Hold on to your seats, it gets hugely confusing.
 The list of Xenix ports:
 Unix System 7 -> Microsoft paid HCR, Montreal, CA to port Unix System 7 to their PDP-11 machine.
 ~1981 Vaporware - used internally on PDP-11s for email, and to try and get the portable C compiler to output Intel Binaries.
 It exists as a brochure, and maybe a mag tape at LCNM+L? but until its read, its unknown. I would bet its only the HCR port with the name change.

← Older revision		Revision as of 04:31, 23 October 2023
Line 237:		Line 237:
	"The data section performs all data operations, such as immediate data value moves . It also contains the barrel shifter, which performs one-cycle shifts of any amount on data." [[User:ForOldHack\|ForOldHack]] ([[User talk:ForOldHack\|ForOldHack]]) 07:37, 22 April 2023‎ (CET)		"The data section performs all data operations, such as immediate data value moves . It also contains the barrel shifter, which performs one-cycle shifts of any amount on data." [[User:ForOldHack\|ForOldHack]] ([[User talk:ForOldHack\|ForOldHack]]) 07:37, 22 April 2023‎ (CET)

−	: The ordering of bytes within words is a function of the [[instruction set architecture]]; i.e. it is built into the ''hardware'' on machines that implement that ISA. ~~All compilers~~ have ''no choice'' but to use the byte ordering that is native to the ISA. [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 00:55, 23 October 2023 (CEST)	+	: The barrel shifter is irrelevant, the issue is the order of short-words in a long-word; switching them around involves plain moves.
		+	: In general, ordering of bytes within words is a function of the [[instruction set architecture]]; i.e. it is built into the ''hardware'' on machines that implement that ISA. Compilers generally have ''no choice'' but to use the byte ordering that is native to the ISA.
		+	: The original C compiler for the 8086 was a bit of an exception to that; the 8086 ISA didn't support long-words ''at all'' - so in that case, the compiler writers ''did'' get to make a choice. Unfortunately, they made the wrong one - they went with the screwy PDP-11 one (which is half big-endian - for the short-words within long-words, and half little-endian - for the bytes within short-words.) [[User:Jnc\|Jnc]] ([[User talk:Jnc\|talk]]) 00:55, 23 October 2023 (CEST)

@@ Line 231: / Line 231: @@
 "For the iAPX 8087 and 287 components to correctly interpret long values, the C compiler must perform a sequence of manipulations. For example, in order to provide support for the 8087 math component, the compiler generates instructions to swap the low word (bytes 0 and 1) with the high word (bytes 2 and 3). The 8087 then is able to operate on the representation it expects. Once the 8087 has completed an operation on a 32-bit value, the two words are swapped back.
-In 1983, Microsoft and Intel were involved in the design of two strategically important projects. Microsoft was developing a new state-of-the-art compiler construction tool and a new C compiler for XENIX 286. At the same time, Intel began a project to support the Universal Development Interface (UDI) and translators ..,for XENIX 286. During the development period, the two companies discovered the incompatibility. After careful analysis, they decided that Microsoft would make the data representation of 32-bit values compatible with the Intel architecture."
+In 1983, Microsoft and Intel were involved in the design of two strategically important projects. Microsoft was developing a new state-of-the-art compiler construction tool and a new C compiler for XENIX 286. At the same time, Intel began a project to support the Universal Development Interface (UDI) and translators .., for XENIX 286. During the development period, the two companies discovered the incompatibility. After careful analysis, they decided that Microsoft would make the data representation of 32-bit values compatible with the Intel architecture."
 Microsoft-C was little-endian and Intel was big-endian or really,
 The DEC VAX was Byte order 3412 ( i.e. Word 2, followed by word 1), and intel was 1234 ( word 1 followed by word 2) , but Microsoft's C compiler for Xenix was 3412, until at least June of 1986, when the 386 came out, which most unfortunately, hampers the performance of Xenix on the i80286 and the i8086, and the i8088. On the Motorola when upgraded to a 68020, there is a barrel shifter which can change the byte ordering in 1 cycle, so Motorola, never cared about the byte ordering.
 "The data section performs all data operations, such as immediate data value moves . It also contains the barrel shifter, which performs one-cycle shifts of any amount on data." [[User:ForOldHack|ForOldHack]] ([[User talk:ForOldHack|ForOldHack]]) 07:37, 22 April 2023‎ (CET)