Talk:Intel 80186

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Here is a reference showing that the original Gateway Handbook never used an Intel 80186, direct form their web site: [1] Samboy 19:50, 24 Apr 2005 (UTC)

[edit] Objection: "UD2 Generate invalid opcode exception"

Here is a reference that 80186 did not introduce UD2 instruction:

Intel Architecture Software Developer's Manual, Volume 2: Instruction Set Reference Manual (Order# 243191, Rev 001, year 1997)

Direct link: http://developer.intel.com/design/pentium/manuals/24319101.pdf ( Found here: http://www.x86.org/intel.doc/186manuals.htm ) page 3-9 (page #39)

says: 1. The UD2 instruction was introduced in the Pentium Pro processor.

My guess is that 80186 introduced the exception, not instruction. —Preceding unsigned comment added by Listic (talk • contribs) 13:42, 12 December 2007 (UTC)

Yes, the 186 added the exception, they did not reserve the ud2 opcode for anything until the Pentium Pro. Still, ud2 wasn't used for anything before the Pentium Pro and generated a #UD exception since the 186. Basically, ud2 always generated an invalid opcode, but before the Pentium Pro, it was just another reserved opcode that future processors may use for something. After the Pentium Pro, ud2 was reserved for the purpose of generating a #UD exception and will do that on all future processors. System86 (talk) 14:30, 14 March 2008 (UTC)