Diag| Considering item [tag:pappp.net,2026-07-22:/2498801] "John C. Dvorak has died"
Diag| Considering item [tag:pappp.net,2026-07-22:/2498669] "Passkeys were invented by engineers with zero understanding of consumer brain"
Diag| Considering item [tag:pappp.net,2026-07-19:/2497943] "Automated Pressure Advance Using a Bed-Leveling Sensor"
Diag| Considering item [tag:pappp.net,2026-07-19:/2497945] "Building an Arch Linux Aarch64 Port for Holo Core"
Diag| Considering item [tag:pappp.net,2026-07-15:/2496852] "Plasma 6.7.3 Complete Changelog"
Diag| Considering item [tag:pappp.net,2026-07-15:/2496709] "Google and Epic give up fighting — third-party Android app stores are coming next week"
Diag| Considering item [tag:pappp.net,2026-07-14:/2496649] "Microsoft’s Secure Boot has been broken for a decade and no one noticed until now"
Diag| Considering item [tag:pappp.net,2026-07-14:/2496563] "Measuring Input Latency on Linux: X11 vs. Wayland, VRR, and DXVK"
Diag| Considering item [tag:pappp.net,2026-07-12:/2496061] "Since Chromium 148, Math.tanh is now fingerprintable to link underlying OS"
Diag| Considering item [tag:pappp.net,2026-07-09:/2495416] "Distributed System Is Slower Than a Laptop"
Diag| Considering item [tag:pappp.net,2026-07-06:/2494320] "Secure Unix ancestor KSOS did type safety before Rust made it cool"
Diag| Considering item [tag:pappp.net,2026-07-06:/2494298] "Zombie ‘who owns Unix?’ lawsuit comes alive again"
Diag| Considering item [tag:pappp.net,2026-07-05:/2494194] "Installing A/UX 1.1 like it's the 90s"
Diag| Considering item [tag:pappp.net,2026-07-01:/2493155] "Physical disc production ending in Jan 2028 for new games on PlayStation"
Diag| Considering item [tag:pappp.net,2026-06-30:/2492846] "Supreme Court Lifts Spending Limits on Political Parties and Candidates"
Diag| Considering item [tag:pappp.net,2026-06-29:/2492593] "US Supreme Court rules geofence warrants require constitutional protections"
Diag| Considering item [tag:pappp.net,2026-06-28:/2492371] "Boffins build a better pixel capable of emitting and receiving light"
Diag| Considering item [tag:pappp.net,2026-06-25:/2490585] "Windows 10 quietly gets one more year of support and updates"
Diag| Considering item [tag:pappp.net,2026-06-24:/2490339] "GitHub shouldn't be a dependency for publishing Rust on crates.io"
Diag| Considering item [tag:pappp.net,2026-06-24:/2490244] "Boffin claims Microsoft’s “quantum leap” is invalid due to “basic Python errors”"
Diag| Considering item [tag:pappp.net,2026-06-24:/2490124] "LineShine Debuts at No. 1 as the TOP500 Enters a New Global Exascale Era"
Diag| Considering item [tag:pappp.net,2026-06-22:/2489670] "Steam Machine"
Diag| Considering item [tag:pappp.net,2026-06-18:/2488796] "What was nice about the UI of Windows 2000"
Diag| Considering item [tag:pappp.net,2026-06-17:/2488496] "Lore – Open source version control system designed for scalability"
Diag| Considering item [tag:pappp.net,2026-06-16:/2488199] "Linux kernel 7.1 sends Intel 486 support to silicon heaven"
Diag| Considering item [tag:pappp.net,2026-06-15:/2487839] "Fox is buying Roku"
Diag| Considering item [tag:pappp.net,2026-06-14:/2487662] "Any road followed precisely to its end leads precisely nowhere."
Diag| Considering item [tag:pappp.net,2026-06-19:/2489115] "I used sound waves to make espresso"
Diag| Considering item [tag:pappp.net,2026-06-10:/2486637] "German court rules Google is liable for whatever Google’s “AI” generates"
Diag| Considering item [tag:pappp.net,2026-06-01:/2484373] "Microsoft is intentionally bricking all Office for Mac 2019/2021 installations"
Diag| Considering item [tag:pappp.net,2026-06-01:/2484272] "Nvidia's Grace Blackwell superchips are officially coming to the PC with RTX Spark notebooks"
Diag| Considering item [tag:pappp.net,2026-05-30:/2483921] "Adding Linux support back for the BASIC (free) version of Vivado"
Diag| Considering item [tag:pappp.net,2026-05-30:/2483835] "Proposed new US funding rules: We can cancel any grant at any time"
Diag| Considering item [tag:pappp.net,2026-05-27:/2483228] "The exemptions in age-verification laws for open source operating systems are bad, actually"
Diag| Considering item [tag:pappp.net,2026-05-31:/2484064] "Mysteries of the Griffin iMate"
Diag| Considering item [tag:pappp.net,2026-05-23:/2482255] "AMD (Xilinx) is Excluding Linux From the Free Tier For Its FPGA Dev Tool"
Diag| Considering item [tag:pappp.net,2026-05-19:/2481210] "The Virtual OS Museum"
Diag| Considering item [tag:pappp.net,2026-05-19:/2481121] "Google changes its search box"
Diag| Considering item [tag:pappp.net,2026-05-15:/2480224] "Windows 11 tests an adjustable taskbar and resizable Start menu"
Diag| Considering item [tag:pappp.net,2026-05-15:/2480167] "Send the arXiv AI-generated slop, get a yearlong vacation from submissions"
Diag| Considering item [tag:pappp.net,2026-05-13:/2479471] "KDE Receives $1.4 Million Investment From Sovereign Tech Fund"
Diag| Considering item [tag:pappp.net,2026-05-12:/2479155] "Google's Android-powered laptops are called Googlebooks, and they're coming this year"
Diag| Considering item [tag:pappp.net,2026-05-07:/2478063] "Canvas is online again after ShinyHunters threaten to leak schools’ data"
Diag| Considering item [tag:pappp.net,2026-05-07:/2477845] "Aramark, University of Kentucky to end partnership, eliminating more than 900 jobs"
Diag| Considering item [tag:pappp.net,2026-04-29:/2475951] "Apple gives up on Vision Pro, disbands Vision Pro team"
Diag| Considering item [tag:pappp.net,2026-04-27:/2475199] "National Science Board eviscerated; Trump admin fires all 22 members"
Diag| Considering item [tag:pappp.net,2026-04-22:/2473947] "Windows 9x Subsystem for Linux"
Diag| Considering item [tag:pappp.net,2026-04-22:/2473882] "Acetaminophen vs. ibuprofen"
Diag| Considering item [tag:pappp.net,2026-04-20:/2473234] "Got an Old Kindle? It Might Not Work Anymore"
Diag| Considering item [tag:pappp.net,2026-04-17:/2472794] "Ban the sale of precise geolocation"
Diag| Considering item [tag:pappp.net,2026-04-15:/2472147] "Academic fraud may be the symptom of a more systemic problem"
Diag| Considering item [tag:pappp.net,2026-04-14:/2471801] "Why Aren’t the Kids Out Protesting Against Trump?"
Diag| Considering item [tag:pappp.net,2026-04-08:/2470398] "I ported Mac OS X to the Nintendo Wii"
Diag| Considering item [tag:pappp.net,2026-03-27:/2467289] "Author of Red Mars calls 'bullshit' on emigrating to the planet"
Diag| Considering item [tag:pappp.net,2026-03-25:/2466758] "Supreme Court rejects Sony's attempt to kick music pirates off the Internet"
Diag| Considering item [tag:pappp.net,2026-03-25:/2466743] "Tracy Kidder has died"
Diag| Considering item [tag:pappp.net,2026-03-23:/2466208] "FCC updates covered list to include foreign-made consumer routers"
Diag| Considering item [tag:pappp.net,2026-03-23:/2466050] "The OpenBSD init system and boot process"
Diag| Considering item [tag:pappp.net,2026-03-22:/2465869] "I hate: Programming Wayland applications"
Diag| Considering item [tag:pappp.net,2026-03-22:/2465853] "Building an FPGA 3dfx Voodoo with Modern RTL Tools"
{"id":60,"date":"2010-04-12T20:16:27","date_gmt":"2010-04-13T00:16:27","guid":{"rendered":""},"modified":"2011-02-02T00:02:50","modified_gmt":"2011-02-02T05:02:50","slug":"the-ugliest-little-reprap-stepper-driver","status":"publish","type":"post","link":"https:\/\/pappp.net\/?p=60","title":{"rendered":"The Ugliest Little RepRap Stepper Driver"},"content":{"rendered":"\n

I’ve been playing with my CNC Mill project a little bit in some “spare” time(= time I should be working on things for school, but can’t focus), and just got my third RepRap Stepper Motor Driver v2.3<\/a> working after some replacement parts and judicious green-wiring<\/a>. <\/p>\n

I bought three drivers as kits, because they were cheap and well regarded, but the boards are largely surface-mount, and the first attempt to populate them didn’t go well, thanks to distorted lead frames and UK’s shifty surface mount equipment. With a little bit of hand soldering to fix lifted pads, I got two of the three boards going, but one of them …ignited… when tested because of a lifted ground on the main IC. The bad board has been sitting in it’s bag waiting for me to do something about it for most of a year now, and the other night I realized I could probably remove the chip, order a replacement Allegro A3982 from one of the electronics suppliers for a couple dollars, and try again. Pulling the chip by hand lifted four pads, but left it looking workable, so I picked up a pair of spare chips from DigiKey (who, for a pleasant but startling change, only charged me a very modest shipping fee). <\/p>\n

My replacements arrived earlier today, and I couldn’t resist taking a crack at it. As the title suggests, this resulted in a UGLY but working driver board (click for larger):
\n\"redwire_sm.jpg\"<\/a>
\nCheck out the run of magnet wire across the bottom of the board, up through a via, and then under the pad it goes to. That is some quality fabrication (also, I checked, that path never carries much current, so magnet wire is OK). The other fixes are all relatively easy (and large-current) runs across one side of the board.<\/p>\n

This time, instead of catching fire and destroying an IDC cable, connecting power and my supremely ghetto-rigged test circuit (a 555 timer set up to generate a pulse train on step, and some buttons and switches to control direction and enable) resulted in a smoothly turning motor. Success. I’ll probably only have to make one more small electronics order (remember that melted IDC cable…) and all the drive electronics will be together to run it from a EMC2\/Linux box. <\/p>\n

The hangup now is the connections between the axes and the drive nuts: my old bent-steel-sheet brackets were not square enough, and were causing walking and uneven tension and all manner of badness, but I haven’t managed to design a replacement I’m both satisfied with and able to build\/source. If anyone has an idea for mounting a 1.25” long, .56” flat-to-flat hexagonal coupling nut to a metal panel 1” away from the rod the nut rides on, which will take large lateral torque and remain square to the rod, let me know. I have a half-baked plan with some modified heavy L-brackets, but there must be something better.<\/p>\n","protected":false},"excerpt":{"rendered":"

I’ve been playing with my CNC Mill project a little bit in some “spare” time(= time I should be working on things for school, but can’t focus), and just got my third RepRap Stepper Motor Driver v2.3 working after some … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,37,1,10,12],"tags":[38,39],"class_list":["post-60","post","type-post","status-publish","format-standard","hentry","category-diy","category-electronics","category-general","category-objects","category-oldblog","tag-reprap","tag-stepper"],"_links":{"self":[{"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/posts\/60","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pappp.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=60"}],"version-history":[{"count":0,"href":"https:\/\/pappp.net\/index.php?rest_route=\/wp\/v2\/posts\/60\/revisions"}],"wp:attachment":[{"href":"https:\/\/pappp.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=60"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pappp.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=60"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pappp.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=60"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}