The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

Author: Ed

  • The Embedded PC’s ISA Bus: Firmware, Gadgets, and Practical Tricks — Unleashed

    ISA Bus Book - Front Cover
    ISA Bus Book – Front Cover

    A long time ago, in a universe far away, I wrote a book that (barely) catapulted me into the ranks of the thousandaires. Time passes, companies get sold / fail / merge / get bought, and eventually the final owners decided to remainder the book; the last royalty check I recall was for $2.88.

    Anyhow, now that it’s discontinued and just as dead as the ISA bus, I own the copyright again and can do this:

    They’re both ZIP files, disguised as ODT files so WordPress will handle them. Just rename them to get rid of the ODT extension, unzip, and you’re good to go. Note, however, that I do retain the copyright, so if you (intend to) make money off them, be sure to tell me how that works for you.

    The big ZIP has the original pages laid out for printing, crop marks and all, so this is not as wonderful a deal as it might first appear. The little ZIP has the files from the diskette, which was unreadable right from the start.

    Words cannot begin to describe how ugly that front cover really is, but Steve’s encomium still makes me smile.

    The text and layout is firmly locked inside Adobe Framemaker files, where it may sleep soundly forever. The only way I can imagine to get it back into editable form would be to install Windows 98 in a VM, install Framemaker, load up the original files, and export them into some non-proprietary format. Yeah, like that would work, even if I had the motivation.

    If you prefer a dead-tree version, they’re dirt cheap from the usual used-book sources. Search for ISBN 1-57398-017-X (yes, X) and you’ll get pretty close.

    Or, seeing as how I just touched the carton of books I’ve been toting all these years, send me $25 (I’m easy to find; if all else fails, look up my amateur callsign in the FCC database) and get an autographed copy direct from the source. Who knows? It might be worth something some day…

    The back cover has some useful info:

    ISA Bus Book - Back Cover
    ISA Bus Book – Back Cover

  • 3D Printing Presentation for Long Island LUG

    Helmet mirror mount - 3D model - Fit layout
    Helmet mirror mount – 3D model – Fit layout

    The folks at the Long Island LUG asked me to give my DIY 3D Printing & the Makerbot Thing-O-Matic presentation, which will happen 11 October at 8 pm. Details & directions at lilug.org.

    Should you happen to be in the area that evening, drop in and pick up a tchotchke!

  • Kensington Trackball: Scroll Ring Tweakage

    Of late, something in the pile of input devices attached to my main PC has been feeding occasional bursts of upward scroll commands, to the extent that editing long documents (something I do quite a bit of, oddly enough) was becoming difficult. By process of elimination, the culprit turned out to be the Kensington trackball to the left of the keyboard: unplugging it eliminated the problem.

    Having had problems with that thing before and having gotten considerable feedback from other folks, I had a general idea of how to proceed: putz with the IR emitter-detector pair, but not very much. A side view of the pair with the trackball cup and scroll ring removed:

    Scroll ring IR emitter-detector quadrature pair
    Scroll ring IR emitter-detector quadrature pair

    Now, what’s weird about that setup is that the detector lens seems to be pointing in the wrong direction: away from the emitter’s lens. You know it’s the detector because it’s tinted: there’s no point in filtering the emitter’s output (although I have seen gray-tinted IR LEDs, which I think is just to mark them as different from visible LEDs). Here’s proof: a pure IR picture from my Sony DSC-F717 in Nightshot (a.k.a. IR) mode through a Hoya R72 visible-block filter:

    Quadrature pair in pure IR
    Quadrature pair in pure IR

    Some possibilities for why the detector is backwards:

    • It’s an assembly screwup (unlikely, but possible)
    • That’s not a lens, it’s a locating tab (different on emitter & detector?)
    • The backside uses the metal conductors as slits to enhance the signal (my favorite)

    Here’s a grossly image-enhanced blowup of the detector from that picture:

    Quadrature IR detector in pure IR - detail
    Quadrature IR detector in pure IR – detail

    The case becomes transparent in pure IR, so you can see the metal lead frame inside. I think they’re using the gaps between the leads to enhance the contrast of the scroll ring edges passing through the beam: absolutely no IR except when a gap aligns with a scroll ring opening.

    [Update: read the comments for a different interpretation; I’m probably wrong.]

    That would also explain why the pair seems so sensitive to alignment: there’s very little IR hitting the detector, because the IR illumination passes through the transparent-to-IR case and vanishes out the far side, with only a tiny bit reflected to the sensor!

    Anyhow, I pushed the pair minutely toward each other, just enough to feel the leads bend, and put everything back together. So far it seems to be working perfectly, but it’s done that before …

    [Comment: Jack found a different solution that might produce better results:

    Just got the Problem with my Scroll ring and thanks to your blog i digged a bit deeper.

    here is the Solution for my Problem:

    I checked this while connected and i found that bending worked only for a short time, so i gave a closer look to the contacts.

    all are soldered from below BUT two contacts are on the upper side.
    normaly solder should flow into but here it was as simple as just resolder the receiver with enough solder an its now working again. (btw a realigned the magnet to get a better response)

    Thanks
    Jack

    ps. the size of the cuts in the metall from the scroll ring differ, a shame for that price..

    It’s certainly worth trying, particularly when your Expert Mouse trackball isn’t working…

    Update: Nine years in the future, a real fix appears!

  • Monthly Aphorism: On Money

    • Money changes everything

    As evidence, read any of the myriad stories about folks receiving a huge slug of windfall cash that subsequently destroys their life. You won’t find many success stories, although that may be a sampling problem.

    My buddy Aitch observes that a corporate implosion often occurs just after completion of a shiny new headquarters building in a far-off location. That construction marks the revenue peak, not necessarily the point where profit margins stabilize.

    And, of course, carpet-bombing a company with C-notes doesn’t guarantee future success, as witness recent developments in the solar power field.

    But the lure of easy money can be exceedingly hard to resist…

        Oh Lord! Let me prove
    Winning a Powerball game
    Would not change me. Much.

    Government-run gambling boils down to a regressive tax on folks who weren’t paying attention during the probability and statistics part of math class. The fact that (some part of) the “profits” go into school budgets  demonstrates that irony remains an integral part of the modern world.

  • External USB Case vs OEM DVD Drive Mounting Bracket

    That little Lenovo Q150 doesn’t include an optical drive and, mostly, I don’t need one, but sometimes it’s handy to boot from a CD. I picked up a used DVD burner that also fits my Dell E1405 laptop (should I need a spare) and a tiny USB laptop drive case from the usual eBay sources for a grand total of $17 delivered.

    The drive had a mounting bracket on the back that obviously had to come off, because the bracket screws snuggled right in among the USB adapter electronics:

    E1405 DVD drive bracket vs USB electronics
    E1405 DVD drive bracket vs USB electronics

    In fact, that flat tab with a hole would have clunked up against the back of the case and prevented it from sliding all the way in, but the screws also foiled Plan B: flip the bracket around so the tab goes under the drive where it couldn’t get lost if I needed it again.

    So now the bracket & screws live in a little bag in the Box o’ USB Stuff.

    The DVD drive works fine with just a single USB cable, although the case came with a power-only USB cable, so the latter also lives in the bag with the bracket. Maybe I’ll need it in the unlikely event I actually burn a DVD in that drive?

  • Shower Faucet Handle Tightening

    Some years back I replaced the shower stall faucets; they’d lasted about half a century, which is good enough. The new faucets were American Standard Cadet/Colony (their choice of name, the current Colony valves seem similar) with a nice, smooth exterior. Of late, both handles had become slightly loose and I finally got around to tightening them.

    Shower faucet valve stem
    Shower faucet valve stem

    The handle setscrews accept a 5/64 inch hex key and pop easily off the stems, revealing the splined plastic (noncorrosive!) mount on the valve stem. The Philips screw in that is what’s loose and allows the whole handle to wiggle just a bit; tightening the setscrew doesn’t help.

    Of course, tightening the screw in the cold water stem tends to open the valve, so you must firmly wedge the splined mount. I’m sure there’s a special wrench for that, but I just held it tightly; next time I’ll try a strap wrench.

    One would ordinarily dose the screws with threadlocker, so as to never have to endure this dance again, but these screws have coarse threads that engage another plastic doodad that engages two wings on the splined mount. So I guess I must retighten them twice a decade or so.

    The handle interiors sport a bit of corrosion (which does not respond to vinegar, so it’s not hard water mineralization), but nothing terrible. The setscrew, mirabile dictu, seems to be stainless steel…

    Shower faucet handle - splines
    Shower faucet handle – splines

  • Corelle Fragments

    I fumble-fingered a plate, it fell between my tummy and the counter, and hit the floor edge-on. There’s a lot of energy stored in that stretched-glass ceramic layer! [Update: The glass is under compression.]

    Shattered Corelle plate on floor
    Shattered Corelle plate on floor

    The fragments tend to be slivers rather than chunks, all with better-than-razor-sharp edges:

    Corelle slivers
    Corelle slivers

    A bit more detail on Corelle in that post…