I'm incredibly pleased to announce that the microcode for the Intel 80386 has been decoded.
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The next best bet is that there is some sort of trigger that will cause the chip to dump its microcode out on its address pins. @kenshirriff found that it should be possible to convince an 8087 to do so - something I still need to verify now that FPGAs no longer scare me.
This logic may only be found in bondout versions of the 286. Who knows. It would take someone staring at the high resolution 286 photos for hundreds of hours to determine if such a mechanism even exists.
If you're up for it:
@gloriouscow @kenshirriff is it not possible for the silicon to be probed directly after it's opened up for die photos? Like attach probe wires with a wire bonding machine. Maybe the microcode section could be cut out from the rest of the die if the rest interferes with the signals.
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@gloriouscow @kenshirriff is it not possible for the silicon to be probed directly after it's opened up for die photos? Like attach probe wires with a wire bonding machine. Maybe the microcode section could be cut out from the rest of the die if the rest interferes with the signals.
Like, theoretically possible with modern technology in a laboratory environment? Yes.
Doable by a hobbyist in their garage? Not so much.
The tiny little gold wires used to bond the die to the package legs look like the trunks of redwood trees at full magnification. The only place to reasonably attach a wire is on one of the pads that were constructed for them.
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Like, theoretically possible with modern technology in a laboratory environment? Yes.
Doable by a hobbyist in their garage? Not so much.
The tiny little gold wires used to bond the die to the package legs look like the trunks of redwood trees at full magnification. The only place to reasonably attach a wire is on one of the pads that were constructed for them.
@ask Further complicating matters is that once you've decapped a chip like this unless you have some sort of professional-grade clean-room filtration setup you've pretty much destroyed it because of all the microscopic schmutz floating in your average air that will get in and start bridging microscopic traces everywhere.
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@thomasfuchs The same CNN process was used to extract the multi-level microcode for the 8087 - the process of decoding that is still on-going.
That chip is insane and @kenshirriff is about our only hope for ever decoding how it works. It has microcode, but there is far less separation between discrete logic and the microcode engine than on conventional CPUs. It's like the roots have grown into all the plumbing, and requites laborious circuit-tracing to understand what the much of the microcode even does.
You can see the extracted 8087 microcode here. No mistakes were ever found or reported:
oh, i actually see someone's opened two issues. i must have missed the email lol
@gloriouscow
All of this is so cool and I'm awed by the amount of effort put in. Thank you!
@thomasfuchs @kenshirriff -
R relay@relay.publicsquare.global shared this topic
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One of my early experiments in OpenCV produced an unintentional piece of Microcode Art I'm still fond of.
This was a result of attempting auto-segmentation using incrementing hue on the various segments. Needless to say, a lovely disaster.
@gloriouscow
Is there an uncompressed version of this file you'd be willing to share? It really is beautiful and I'm wondering how it would look printed out and framed. -
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.
#retrocomputing #vintagecomputing #microcode #reverseengineering
Here's a little bit of banana for scale to appreciate how tiny the features we're working with are.
I have this acrylic keychain that has an actual 386 die in it.
It's Today's Choice, you see. (The rear side has a 486 die, with "Tomorrows Vision" labelled above it, something that I will never get tired of reading. Oh my god, I'm so old.)
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Here's a little bit of banana for scale to appreciate how tiny the features we're working with are.
I have this acrylic keychain that has an actual 386 die in it.
It's Today's Choice, you see. (The rear side has a 486 die, with "Tomorrows Vision" labelled above it, something that I will never get tired of reading. Oh my god, I'm so old.)
See the tiny little darker-color square on the lower left? That's the microcode array, all 94,720 bits of it.
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@gloriouscow
Is there an uncompressed version of this file you'd be willing to share? It really is beautiful and I'm wondering how it would look printed out and framed.@bitcrush_io Sadly I don't. I was rapidly filling up my hard drive with hundreds of very large images being generated from the over 50 different python scripts I wrote over the course of bit extraction and the original full resolution version got accidentally deleted in a clean-up
I likely have the original script that made it, and I might be able to reproduce it if I can determine the original parameters that I used, but it will take some fiddling. I was running scripts on some post-processed versions of the input image as well so there's really no telling if I'll find the right combination. Bummer.
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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.
#retrocomputing #vintagecomputing #microcode #reverseengineering
@gloriouscow@oldbytes.space how long until the 486? that's the one i am most interested in
(only half joking...) -
@bitcrush_io Sadly I don't. I was rapidly filling up my hard drive with hundreds of very large images being generated from the over 50 different python scripts I wrote over the course of bit extraction and the original full resolution version got accidentally deleted in a clean-up
I likely have the original script that made it, and I might be able to reproduce it if I can determine the original parameters that I used, but it will take some fiddling. I was running scripts on some post-processed versions of the input image as well so there's really no telling if I'll find the right combination. Bummer.
@gloriouscow
Totally understandable, and certainly no need to do all that on my account. If you did find the script, I imagine there's all kinds of variations on this idea that would look fantastic without needing to recreate this image exactly. -
@gloriouscow
Totally understandable, and certainly no need to do all that on my account. If you did find the script, I imagine there's all kinds of variations on this idea that would look fantastic without needing to recreate this image exactly.@bitcrush_io That is true. I think a version without the black might look better.
I think the complete lack of intention behind it is something magical though.
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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.
#retrocomputing #vintagecomputing #microcode #reverseengineering
Goddamn incredible
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Here's a little bit of banana for scale to appreciate how tiny the features we're working with are.
I have this acrylic keychain that has an actual 386 die in it.
It's Today's Choice, you see. (The rear side has a 486 die, with "Tomorrows Vision" labelled above it, something that I will never get tired of reading. Oh my god, I'm so old.)
@gloriouscow I have to assume those dies must have failed QA because otherwise those must have been really expensive keychains.
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@gloriouscow I have to assume those dies must have failed QA because otherwise those must have been really expensive keychains.
@whimsy I would assume so.
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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.
#retrocomputing #vintagecomputing #microcode #reverseengineering
@gloriouscow I just wanna say as an Old Skool nerd, this is absolutely amazing. As John and Hank Green would say, this is definitely committing to the bit. Bravo!
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@bitcrush_io That is true. I think a version without the black might look better.
I think the complete lack of intention behind it is something magical though.
@bitcrush_io so, good news! I've been able to recover this particular disaster workflow.
I'm not sure the exact parameters so an exact recreation may not be possible, but I was able to produce these. Which one do you like best? (the upper-left one is the original, for comparison).
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Here's a little bit of banana for scale to appreciate how tiny the features we're working with are.
I have this acrylic keychain that has an actual 386 die in it.
It's Today's Choice, you see. (The rear side has a 486 die, with "Tomorrows Vision" labelled above it, something that I will never get tired of reading. Oh my god, I'm so old.)
@gloriouscow This weirdly reminds me of those plastic trinkets you used to get that contained """real""" moon dust
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@gloriouscow This weirdly reminds me of those plastic trinkets you used to get that contained """real""" moon dust
@lunarloony there's actually a shit ton of moon dust out there, they brought back 842 pounds rock and soil over all the Apollo missions
I'm not sure I'd be confident about any random keychain, but its not infeasible. It's fun reading about how many moon rocks were stolen or lost, too.
Here’s All the Rocks We Hauled Back From the Moon
The 12 human beings who walked on the Moon collected, catalogued and returned 842 pounds of lunar rock and soil. Each sample has been meticulously documented in NASA's Lunar Sample Catalog.
Beautiful Public Data (www.beautifulpublicdata.com)
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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.
#retrocomputing #vintagecomputing #microcode #reverseengineering
@gloriouscow I was so excited to get a machine with a 386 + math coprocessor when I was 16 y/o. I didn't yet know there was microcode fetching, decoding, and executing the instructions.
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It's fairly easy to visually decode them. But now just do that 94,000 times.
@gloriouscow a couple OSM nerds and less than a week.. sounds doable.
