Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×
United Kingdom Hardware Technology

Celebrating ARM's 25th Anniversary With the Visual ARM1 (visual6502.org) 37

In a slow-burn series of posts going back to 2010, the Visual6502.org has presented diagrams and commentary on "ancient microchips," mosly based on painstaking microphotography after just-as-painstaking depackaging and cleaning of the actual chips.Today, reader trebonian writes an excerpt from their latest entry, in honor of the 25th anniversary of ARM Ltd., UK, which is somewhat different: To celebrate and honor their amazing work, we present the Visual ARM1, created in collaboration with some of ARM's founding engineers.

Designed by Sophie Wilson and Steve Furber before there was an ARM Ltd., the Acorn RISC Machine was the first of a line of processors that power our cell phones and tablets today. Unlike our projects based on microscope images, the Visual ARM was created from a resurrected .cif chip layout file, used under our license agreement with ARM. We also photographed one of the few ARM1 chips at very high resolution, and our photograph is featured at the Centre for Computing History in Cambridge.

Credit goes to ARM founding engineers John Biggs for inspiring the project, discovering the tape, and recovering a usable .cif file, Lee Smith for spotting the variable record format used to encode the file (an artifact of the VMS on Acorn's VAX that at first appeared to be widespread corruption of the file), to Cambridge University Computing Services for reading the Exabyte tape, and to ARM founder Dave Howard for help unraveling the VLSI CIF dialect. Our chip simulation and visualization was developed by Barry Silverman, Brian Silverman, Ed Spittles, and Greg James.

This discussion has been archived. No new comments can be posted.

Celebrating ARM's 25th Anniversary With the Visual ARM1

Comments Filter:
  • by davmoo ( 63521 ) on Saturday November 28, 2015 @02:47AM (#51016571)

    Shouldn't there be a link in there somewhere?

  • by Rosco P. Coltrane ( 209368 ) on Saturday November 28, 2015 @03:45AM (#51016653)

    is that reading and exploiting data that's a mere 25 years old requires almost archeological-like recovery and reconstruction techniques. Compare that to a thousand year old book that's usually pretty much readily readable today.

    I think modern society is on a scary path towards massive amnesia in the not-so-long term...

    • Comment removed based on user account deletion
      • by mikael ( 484 )

        Some videos had network based DRM (RealPlayer?) What happens when the server goes away? It's impossible to play the video. The server has gone along with the decryption keys. It's no different from those ironworks companies that make cast iron drain covers and put their web address on top. 10 years later, they are bought out and change their name, and drop the domain name.

      • by bondsbw ( 888959 ) on Saturday November 28, 2015 @12:34PM (#51017937)

        I'm not so sure this is going to be as big of a problem going forward. The abundance of formats and specialized hardware were due largely to the lack of standardization. And just getting the system to have acceptable performance often required tweaking not machine code, but the hardware itself.

        Today we solve many more problems using general purpose hardware and software written in well-documented languages, and open-source is making that documentation live much longer than it might otherwise.

        Plus the Internet in general has transformed the idea of archiving.

    • by GuB-42 ( 2483988 )

      That's outdated confidential data, these tend to disappear easily. It wasn't different in the old days. The thousand year books are either exceptional or widely published. This is BTW one the reasons the patent system was created.
      Books still exist. And we even make paper specially designed to last a very, very long time.

    • by Anonymous Coward

      Many ancient writings are only "readable" in the sense that you can see them, and they appear to possibly be some sort of writing. But interpreting them is either impossible, or it's almost total guesswork.

      It's the exact same problem that we see here: the media is accessible, but the interpretation of it is unknown.

      That's the hard part. Figuring out just what the fuck the writing actually says, when there's nobody around who natively understands the format of it.

    • Except the ones written in dead dialects that people spend years, decades or centuries decoding. And that's after the extraordinary luck fhat the book sven survived very long in the first place.

    • by Osgeld ( 1900440 )

      well if those books were written by a privet sect where only a dozen people knew the language a thousand years ago you might have a fair comparison

    • by tlhIngan ( 30335 )

      is that reading and exploiting data that's a mere 25 years old requires almost archeological-like recovery and reconstruction techniques. Compare that to a thousand year old book that's usually pretty much readily readable today.

      it's called bit-rot and it takes place in two ways.

      First is the media rots - and 25 years is a really long time - most magnetic media, and even pressed optical media (CDs) have already started failing inside of 10 years. Especially finicky things like floppies. Basically the media d

  • by 93 Escort Wagon ( 326346 ) on Saturday November 28, 2015 @04:07AM (#51016683)

    Is that referring to data stored on a magnetic tape using varying record lengths? This used to be pretty common. The first record would be a text file telling you how the rest of the tape was formatted (although sometimes that descriptive "record" was a separate piece of paper attached to the spool).

    Ah, those were the days, having to load reel-to-reel tapes by hand, hard drives the size of washing machines...

    • How the [beep] would you make a text file in the beginning if you at this moment don't fully know what would be the rest? And how can you write it afterwards if there is logically NO data after the last record on the tapes?

      $ man tar

      • How the [beep] would you make a text file in the beginning if you at this moment don't fully know what would be the rest?

        What you apparently don't know is that the unstructured file is basically a Unix feature. Before that, computers overwhelmingly had structured data. You knew precisely what kind of data would be in a file because you defined the file structure when you created it. Consequently, a description of the data format already existed. Ever created an application on a mainframe? Guess not.

    • Interesting that they struggled to find an Exabyte drive - those used to be the way you'd send audio to a CD pressing plant. I'd have thought there should be a bunch of them knocking around...

      • by Anonymous Coward

        I'm freaking ASTOUNDED that it could read the tape. We had a *lot* of exabyte drives where I worked, and (as sysadmin) I did a lot of backups onto them.

        And, as a responsible sysadmin, I checked them... and OFTEN found that drive A could not read (at all!) tapes written with drive B (though sometimes the drive B could read tapes written on drive A). Occasionally, tapes written on drive A could not be read by drive A...

        Luckily, we nearly never had to get stuff off of tape. Exabyte drives are the least reli

  • by aglider ( 2435074 ) on Saturday November 28, 2015 @04:41AM (#51016721) Homepage
    The fact is that on mobile phones and tablets, Firefox is not displaying any "green on green" link.
    The other fact is that a link, which comes at a very competitive price nowadays, could have been added within the article.
    Well, the string spelling the link IS inside the article, only it's not marked up as a link.
    Ah, all those insensitive TXT clods!
    • The fact is that on mobile phones and tablets, Firefox is not displaying any "green on green" link. The other fact is that a link, which comes at a very competitive price nowadays, could have been added within the article. Well, the string spelling the link IS inside the article, only it's not marked up as a link. Ah, all those insensitive TXT clods!

      Give em a break, it's 25 year old technology....

  • I bought an Acorn Archimedes 305 [wikipedia.org] in 1987, it had an ARM2 CPU at 4/8 MHz. It was one of the first available ARM systems (only preceded by an £4000 expansion box for the Acorn BBC B [wikipedia.org] and a developer version of the Archimedes which was not available to the public), and the first ARM system which was affordable. It came with the Arthur 0.2 Operating System in EPROM, which was later replaced by RISC OS 1.2.

    I learned ARM assembly programming from Pete Cockerell's excellent book [peter-cockerell.net].

    Today, ARM is known for
  • I think the 3Hz visual simulation of the cpu you get to by clicking the image in the article is rather fun. Great way to understand clock cycles and what computing involves.

"Show me a good loser, and I'll show you a loser." -- Vince Lombardi, football coach

Working...