<![CDATA[I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded.]]>I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded.

It was an group effort by a bunch of talented people to extract and correct the physical bits, but the major work of decoding them was done by reenigne - you may know him from such incredible PC demos as 8088 MPH and Area 5150, as well as being the person who decoded the 8088 microcode previously.

Please, check out his writeup.

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80386 microcode disassembled « Reenigne blog

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(www.reenigne.org)

]]>https://board.circlewithadot.net/topic/1ac11314-e4e1-4896-9910-802ec43a4ff5/i-m-incredibly-pleased-to-announce-that-the-microcode-for-the-intel-80386-has-been-decoded.RSS for NodeMon, 25 May 2026 10:06:30 GMTSat, 23 May 2026 15:50:26 GMT60<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:49:45 GMT]]>@ldcd @gloriouscow Ah, adding some H2O2 to HCl speeds things up by a lot. Also makes it fume chlorine, so a fume hood is recommended for obvious reasons.

@gloriouscow do you think you could supply some? Both of you are likely on the same continent, no? Otherwise I can do it.

]]>https://board.circlewithadot.net/post/https://infosec.exchange/users/infosecdj/statuses/116626331086486358https://board.circlewithadot.net/post/https://infosec.exchange/users/infosecdj/statuses/116626331086486358Sat, 23 May 2026 22:49:45 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:46:46 GMT]]>Each microcode word on the 386 is 37 bits long. So each of these rows of microcode bits contributes one bit to the resulting microcode word.

A PLA activates the columns of the microcode ROM from above, column-wise, and from the left side, via multiplexers, ultimately activating exactly 37 cell positions for each microcode address.

]]>https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626319401996626https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626319401996626Sat, 23 May 2026 22:46:46 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:45:12 GMT]]>@infosecdj @gloriouscow spiked HCl?

I don't do much semiconductor processing but I can give that a go; we're not allowed to bring any solvent to the acid bench so if you have any dies free of epoxy (but not necessarily delayered) that would be ideal

]]>https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626313229773244https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626313229773244Sat, 23 May 2026 22:45:12 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:44:27 GMT]]>I think this image deserves a tiny bit of explanation. What are we looking at here?

Well, it's a direct mapping of the microcode array to a bitmap, where black (0) is no transistor and white (1) is a transistor.

Overlaid on the actual microcode die photo mosaic, it looks like this.

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]]>https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626310239123956https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626310239123956Sat, 23 May 2026 22:44:27 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:26:09 GMT]]>@ldcd @gloriouscow Exactly one for now. Can make more if needed. Using RIE to strip the die is rather expensive though, just HF for oxide removal and spiked HCl for metal would do the job of getting to the substrate quickly.

]]>https://board.circlewithadot.net/post/https://infosec.exchange/users/infosecdj/statuses/116626238283019598https://board.circlewithadot.net/post/https://infosec.exchange/users/infosecdj/statuses/116626238283019598Sat, 23 May 2026 22:26:09 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:23:30 GMT]]>@infosecdj @gloriouscow how many delayered 286s do you have? My training is expired on the RIE tool and it's also super oversubscribed

]]>https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626227911170335https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626227911170335Sat, 23 May 2026 22:23:30 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:22:33 GMT]]>@infosecdj @gloriouscow ok perfect that's what I was hoping, shouldn't be too hard to etch off

]]>https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626224136047396https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626224136047396Sat, 23 May 2026 22:22:33 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:21:40 GMT]]>@ldcd Yeah, I have no idea. I shouldn't be allowed in the average kitchen let alone a chemistry lab.

If you have unanswered questions I could get you in touch with someone, but they're the person who wrote that

]]>https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626220699978937https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626220699978937Sat, 23 May 2026 22:21:40 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:20:30 GMT]]>@gloriouscow @ldcd Aluminium, the die is too old to have any copper on it.

]]>https://board.circlewithadot.net/post/https://infosec.exchange/users/infosecdj/statuses/116626216116971320https://board.circlewithadot.net/post/https://infosec.exchange/users/infosecdj/statuses/116626216116971320Sat, 23 May 2026 22:20:30 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:19:55 GMT]]>@gloriouscow just like a checklist for the process, IE any device cleaning steps, acid mixture, times and heating required, but the siliconpr0n linked is probably good enough

]]>https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626213779186291https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626213779186291Sat, 23 May 2026 22:19:55 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:18:32 GMT]]>@ldcd @infosecdj can you answer this?

]]>https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626208347403221https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626208347403221Sat, 23 May 2026 22:18:32 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:17:58 GMT]]>@ldcd sorry what's a rough traveller?

I can get 286 chips to you but I have no real experience with or equipment for decapping here.

]]>https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626206100381182https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626206100381182Sat, 23 May 2026 22:17:58 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:16:30 GMT]]>@gloriouscow do you know what M1 is on the 286 so I can etch any of the metal there away

]]>https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626200372801033https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626200372801033Sat, 23 May 2026 22:16:30 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:15:51 GMT]]>@gloriouscow https://siliconpr0n.org/wiki/doku.php?id=delayer:dash

Ok yeah if it doesn't require any heating I can run this on a delayered die next time I'm working at the acid bench in the cleaneoom

]]>https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626197838693976https://board.circlewithadot.net/post/https://social.treehouse.systems/users/ldcd/statuses/116626197838693976Sat, 23 May 2026 22:15:51 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:10:43 GMT]]>@gloriouscow @ask Normally I'm working on embedded parts that don't generate enough heat for this to be a problem

]]>https://board.circlewithadot.net/post/https://ioc.exchange/users/azonenberg/statuses/116626177650978997https://board.circlewithadot.net/post/https://ioc.exchange/users/azonenberg/statuses/116626177650978997Sat, 23 May 2026 22:10:43 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 22:09:26 GMT]]>@azonenberg @ask

how does heat dissipation work when a chip is decapped? I would have assumed a CPU would immediately overheat

]]>https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626172579594815https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626172579594815Sat, 23 May 2026 22:09:26 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 21:38:27 GMT]]>@gloriouscow @ask well what i meant is more, dust on the top of a decapped chip with intact bond wires and passivation isn't really going to hurt it. I've had chips sitting on a shelf in a cabinet for years open cavity that still run fine.

]]>https://board.circlewithadot.net/post/https://ioc.exchange/users/azonenberg/statuses/116626050739288150https://board.circlewithadot.net/post/https://ioc.exchange/users/azonenberg/statuses/116626050739288150Sat, 23 May 2026 21:38:27 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 21:34:58 GMT]]>@azonenberg @ask

true, the amount of delayering you need to get images of things isn't necessarily required if you were just going to try to probe things.

i still think that fact that everything is incredibly tiny is the real problem.

]]>https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626037072570056https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116626037072570056Sat, 23 May 2026 21:34:58 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 21:27:18 GMT]]>@gloriouscow I’m so excited about a real 386 MiSTer core!

]]>https://board.circlewithadot.net/post/https://bitbang.social/users/nizmow/statuses/116626006884807866https://board.circlewithadot.net/post/https://bitbang.social/users/nizmow/statuses/116626006884807866Sat, 23 May 2026 21:27:18 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 21:24:23 GMT]]>@infosecdj @gloriouscow

You can find my OrcID in my profile bio. And this is our research institute's webpage

https://www.bmo.uni-luebeck.de/

]]>https://board.circlewithadot.net/post/https://chaos.social/users/datenwolf/statuses/116625995404331023https://board.circlewithadot.net/post/https://chaos.social/users/datenwolf/statuses/116625995404331023Sat, 23 May 2026 21:24:23 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 21:23:48 GMT]]>@infosecdj @datenwolf

If I can help coordinate this in any way left me know. I'd be happy to reimburse you for shipping things - although through some other means besides Ted Pella 😄

]]>https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116625993119627114https://board.circlewithadot.net/post/https://oldbytes.space/users/gloriouscow/statuses/116625993119627114Sat, 23 May 2026 21:23:48 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 21:22:21 GMT]]>@datenwolf @gloriouscow I think I can provide a few. At least I have the one that was imaged, and I could also try to get you one more with the die stripped down to substrate.

]]>https://board.circlewithadot.net/post/https://infosec.exchange/users/infosecdj/statuses/116625987430041819https://board.circlewithadot.net/post/https://infosec.exchange/users/infosecdj/statuses/116625987430041819Sat, 23 May 2026 21:22:21 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 21:18:24 GMT]]>@gloriouscow oh really neat

]]>https://board.circlewithadot.net/post/https://adhd.irenes.space/users/ireneista/statuses/01KSBB86T4RTMD862NCQBQWH7Dhttps://board.circlewithadot.net/post/https://adhd.irenes.space/users/ireneista/statuses/01KSBB86T4RTMD862NCQBQWH7DSat, 23 May 2026 21:18:24 GMT<![CDATA[Reply to I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded. on Sat, 23 May 2026 21:16:03 GMT]]>@infosecdj @gloriouscow

I'll need a decapped 80286 first. I think I might have a few AMD made 286 somewhere in the basement, but I have zero experience in decapping.

]]>https://board.circlewithadot.net/post/https://chaos.social/users/datenwolf/statuses/116625962682660528https://board.circlewithadot.net/post/https://chaos.social/users/datenwolf/statuses/116625962682660528Sat, 23 May 2026 21:16:03 GMT