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.

Category: Software

General-purpose computers doing something specific

  • EMC2 Logitech GamePad: Triggger Button Name Change

    I just updated EMC2 on the Sherline CNC mill from 2.4.6 to 2.4.7 (which mis-identifies itself as 2.4.6 on the splash screen) and the Axis UI failed to start. A bit of digging shows that the name of Button 1 (the left button in the right-hand quad, clearly labeled 1) has inexplicably changed from btn-trigger to btn-joystick.

    Logitech Gamepad Pendant
    Logitech Gamepad Pendant

    Most likely the change has nothing to do with EMC2, because (I think) those names bubble up from the HID driver that actually talks to the hardware and that stuff has also been updated; this is all on Ubuntu 10.04 LTS. But in any event, the name is now different.

    That requires a tweak to the Eagle schematics, which will regenerate Logitech_Gamepad.hal, but you can just edit the latter file and change btn-trigger to btn-joystick.

    As nearly as I can tell, changing the pin name in the Logitech library component, saving the library, then updating the library in the schematic doesn’t do squat. Evidently, Eagle keeps track of which components you’ve used and won’t update them unless you do some manual gymnatistics, which makes a certain amount of sense.

    That means one must:

    • Delete both “gates” of the old component (INPUT.0.BUTTONS first, then INPUT.0)
    • Make sure you’re on Page 2 where the basic gate will go
    • Add the revised LOGITECH_DUAL_ACTION_GAMEPAD to get the INPUT.1 “gate”
    • Rename it to INPUT.0
    • Use Move to jiggle it around a bit to ensure its pins get hitched up to the existing nets
    • Switch to Page 1 where the button nets lie in wait
    • Type invoke input.0 into the Eagle command line
    • Pick -BUTTONS from the list to select that “gate”
    • Position that gate appropriately
    • Use Move to jiggle the gate
    • Save everything
    • Run the Eagle2Hal ULP to get a new HAL output file
    • Put that file where it’ll do the most good

    There, now, wasn’t that obvious?

    The modified Logitech_Gamepad.hal file:

    # HAL config file automatically generated by Eagle-CAD ULP:
# [/mnt/bulkdata/Project Files/eagle/ulp/hal-write-2.4.ulp]
# (C) Martin Schoeneck.de 2008
# Mods Ed Nisley 2010
# Path        [/mnt/bulkdata/Project Files/eagle/projects/EMC2 HAL Configuration/]
# ProjectName [Logitech Gamepad - 2.4.7]
# File name   [/mnt/bulkdata/Project Files/eagle/projects/EMC2 HAL Configuration/Logitech Gamepad - 2.4.7.hal]
# Created     [10:40:31 11-Nov-2011]

####################################################
# Load realtime and userspace modules
loadrt constant		count=16
loadrt and2		count=17
loadrt flipflop		count=4
loadrt mux2		count=5
loadrt mux4		count=1
loadrt not		count=8
loadrt or2		count=10
loadrt scale		count=7
loadrt timedelay		count=1
loadrt toggle		count=1
loadrt wcomp		count=6

####################################################
# Hook functions into threads
addf toggle.0		servo-thread
addf wcomp.1		servo-thread
addf wcomp.2		servo-thread
addf wcomp.3		servo-thread
addf and2.0		servo-thread
addf and2.4		servo-thread
addf and2.3		servo-thread
addf and2.2		servo-thread
addf and2.1		servo-thread
addf constant.6		servo-thread
addf constant.5		servo-thread
addf constant.4		servo-thread
addf constant.3		servo-thread
addf constant.2		servo-thread
addf constant.1		servo-thread
addf constant.0		servo-thread
addf constant.7		servo-thread
addf constant.8		servo-thread
addf scale.1		servo-thread
addf scale.2		servo-thread
addf scale.3		servo-thread
addf mux4.0		servo-thread
addf mux2.0		servo-thread
addf scale.4		servo-thread
addf scale.0		servo-thread
addf wcomp.5		servo-thread
addf wcomp.4		servo-thread
addf wcomp.0		servo-thread
addf flipflop.1		servo-thread
addf flipflop.0		servo-thread
addf and2.5		servo-thread
addf and2.6		servo-thread
addf and2.7		servo-thread
addf and2.8		servo-thread
addf flipflop.2		servo-thread
addf flipflop.3		servo-thread
addf or2.4		servo-thread
addf or2.8		servo-thread
addf or2.7		servo-thread
addf or2.6		servo-thread
addf or2.5		servo-thread
addf or2.3		servo-thread
addf or2.2		servo-thread
addf or2.1		servo-thread
addf or2.0		servo-thread
addf not.1		servo-thread
addf not.2		servo-thread
addf not.3		servo-thread
addf not.4		servo-thread
addf not.5		servo-thread
addf not.6		servo-thread
addf not.7		servo-thread
addf not.0		servo-thread
addf constant.9		servo-thread
addf mux2.1		servo-thread
addf mux2.2		servo-thread
addf mux2.3		servo-thread
addf mux2.4		servo-thread
addf constant.10		servo-thread
addf constant.11		servo-thread
addf scale.5		servo-thread
addf scale.6		servo-thread
addf constant.12		servo-thread
addf constant.13		servo-thread
addf timedelay.0		servo-thread
addf constant.14		servo-thread
addf constant.15		servo-thread
addf and2.16		servo-thread
addf and2.15		servo-thread
addf and2.14		servo-thread
addf and2.13		servo-thread
addf and2.12		servo-thread
addf and2.11		servo-thread
addf and2.10		servo-thread
addf and2.9		servo-thread
addf or2.9		servo-thread

####################################################
# Set parameters

####################################################
# Set constants
setp constant.0.value	+0.02
setp constant.1.value	-0.02
setp constant.2.value	60
setp constant.3.value	1.00
setp constant.4.value	0.10
setp constant.5.value	0.50
setp constant.6.value	0.10
setp constant.7.value	+0.5
setp constant.8.value	-0.5
setp constant.9.value	0.0
setp constant.10.value	[TRAJ]MAX_LINEAR_VELOCITY
setp constant.11.value	[TRAJ]MAX_ANGULAR_VELOCITY
setp constant.12.value	-1.0
setp constant.13.value	0.1
setp constant.14.value	0.020
setp constant.15.value	0.000

####################################################
# Connect Modules with nets
net a-button-minus or2.2.in0 input.0.btn-joystick and2.15.in0
net a-button-plus or2.2.in1 input.0.btn-thumb2 and2.16.in0
net a-buttons-active or2.2.out or2.3.in0 or2.4.in1
net a-disable not.7.out and2.5.in1
net a-enable or2.4.in0 flipflop.3.out not.7.in mux2.4.sel
net a-jog wcomp.2.in input.0.abs-z-position mux2.4.in1
net a-knob-active not.2.out and2.7.in1
net a-knob-inactive wcomp.2.out not.2.in and2.6.in1
net a-select and2.8.in0 and2.7.out
net a-set flipflop.3.set and2.8.out
net angular_motion or2.4.out mux2.0.sel
net any-buttons-active mux4.0.sel0 or2.8.out
net az-buttons-active or2.3.out or2.8.in1 or2.9.in0
net az-reset flipflop.2.reset and2.6.out flipflop.3.reset
net button-crawl scale.4.out mux4.0.in3
net button-fast scale.2.out mux4.0.in1 scale.4.in
net jog-crawl toggle.0.out mux4.0.sel1
net jog-speed halui.jog-speed mux4.0.out
net knob-crawl mux4.0.in2 scale.3.out
net knob-fast mux4.0.in0 scale.1.out scale.3.in
net n_1 constant.10.out mux2.0.in0
net n_2 and2.0.in0 input.0.btn-top2
net n_3 and2.0.in1 input.0.btn-base
net n_4 and2.0.out halui.abort
net n_5 halui.mode.manual input.0.btn-base3
net n_6 wcomp.0.max wcomp.1.max wcomp.2.max wcomp.3.max constant.0.out
net n_7 halui.program.resume input.0.btn-base4
net n_8 wcomp.0.min wcomp.1.min wcomp.2.min wcomp.3.min constant.1.out
net n_9 mux2.0.in1 constant.11.out
net n_10 constant.12.out scale.5.gain scale.6.gain
net n_11 or2.0.in0 input.0.btn-base5
net n_12 or2.0.in1 input.0.btn-base6
net n_13 constant.9.out mux2.1.in0 mux2.2.in0 mux2.3.in0 mux2.4.in0
net n_14 mux2.1.out halui.jog.0.analog
net n_15 toggle.0.in or2.0.out
net n_16 constant.2.out scale.0.gain
net n_17 constant.5.out scale.1.gain
net n_18 constant.3.out scale.2.gain
net n_19 constant.4.out scale.3.gain
net n_20 scale.4.gain constant.6.out
net n_21 halui.jog.1.analog mux2.2.out
net n_22 mux2.2.in1 scale.5.out
net n_23 scale.6.out mux2.3.in1
net n_24 constant.13.out halui.jog-deadband
net n_25 wcomp.4.max constant.7.out wcomp.5.max
net n_26 constant.8.out wcomp.4.min wcomp.5.min
net n_27 mux2.3.out halui.jog.2.analog
net n_28 halui.jog.3.analog mux2.4.out
net n_29 timedelay.0.out and2.9.in1 and2.10.in1 and2.12.in1 and2.11.in1 and2.13.in1 and2.14.in1 and2.16.in1 and2.15.in1
net n_30 and2.9.out halui.jog.0.minus
net n_31 or2.9.out timedelay.0.in
net n_32 constant.14.out timedelay.0.on-delay
net n_33 constant.15.out timedelay.0.off-delay
net n_34 and2.10.out halui.jog.0.plus
net n_35 and2.11.out halui.jog.1.minus
net n_36 halui.jog.1.plus and2.12.out
net n_37 and2.13.out halui.jog.2.minus
net n_38 and2.14.out halui.jog.2.plus
net n_39 and2.15.out halui.jog.3.minus
net n_40 and2.16.out halui.jog.3.plus
net vel-per-minute scale.0.out scale.1.in scale.2.in
net vel-per-second mux2.0.out scale.0.in
net x-buttons-active or2.7.in0 or2.5.out
net x-disable not.4.out and2.4.in1
net x-enable not.4.in flipflop.0.out mux2.1.sel
net x-hat-jog wcomp.4.in input.0.abs-hat0x-position
net x-hat-minus wcomp.4.under or2.5.in1 and2.9.in0
net x-hat-plus or2.5.in0 wcomp.4.over and2.10.in0
net x-jog wcomp.0.in input.0.abs-x-position mux2.1.in1
net x-knob-active not.0.out and2.1.in0
net x-knob-inactive wcomp.0.out not.0.in and2.2.in0 and2.3.in0
net x-set and2.1.out flipflop.0.set
net xy-buttons-active or2.7.out or2.8.in0 or2.9.in1
net xy-reset flipflop.0.reset and2.2.out flipflop.1.reset
net y-buttons-active or2.6.out or2.7.in1
net y-disable not.5.out and2.1.in1
net y-enable flipflop.1.out not.5.in mux2.2.sel
net y-hat-jog wcomp.5.in input.0.abs-hat0y-position
net y-hat-minus wcomp.5.under or2.6.in1 and2.12.in0
net y-hat-plus or2.6.in0 wcomp.5.over and2.11.in0
net y-jog wcomp.1.in input.0.abs-y-position scale.5.in
net y-knob-active not.1.out and2.3.in1
net y-knob-inactive not.1.in wcomp.1.out and2.2.in1
net y-select and2.4.in0 and2.3.out
net y-set flipflop.1.set and2.4.out
net z-button-minus or2.1.in0 input.0.btn-thumb and2.13.in0
net z-button-plus or2.1.in1 input.0.btn-top and2.14.in0
net z-buttons-active or2.1.out or2.3.in1
net z-disable not.6.out and2.8.in1
net z-enable not.6.in flipflop.2.out mux2.3.sel
net z-jog wcomp.3.in input.0.abs-rz-position scale.6.in
net z-knob-active not.3.out and2.5.in0
net z-knob-inactive not.3.in wcomp.3.out and2.7.in0 and2.6.in0
net z-set and2.5.out flipflop.2.set

  • OpenSCAD: Useful Sizes file

    My Useful Sizes.scad file has been accumulating the dimensions of nuts & bolts & a motor that don’t (seem to) appear elsewhere in the OpenSCAD universe:

    //-- Useful sizes

Tap2_56 = 0.070 * inch;
Clear2_56 = 0.082 * inch;
Head2_56 = 0.156 * inch;
Head2_56Thick = 0.055 * inch;
Nut2_56Dia = 0.204 * inch;
Nut2_56Thick = 0.065 * inch;

Tap3_48 = 0.079 * inch;
Clear3_48 = 0.096 * inch;
Head3_48 = 0.184 * inch;
Head3_48Thick = 0.058 * inch;
Nut3_48Dia = 0.201 * inch;
Nut3_48Thick = 0.073 * inch;

Tap4_40 = 0.089 * inch;
Clear4_40 = 0.110 * inch;
Head4_40 = 0.211 * inch;
Head4_40Thick = 0.065 * inch;
Nut4_40Dia = 0.228 * inch;
Nut4_40Thick = 0.086 * inch;

Tap10_32 = 0.159 * inch;
Clear10_32 = 0.190 * inch;
Head10_32 = 0.373 * inch;
Head10_32Thick = 0.110 * inch;
Nut10_32Dia = 0.433 * inch;
Nut10_32Thick = 0.130 * inch;

Tap025_20 = 0.201 * inch;
Clear025_20 = 0.2660 * inch;
Head025_20 = 0.492 * inch;
Head025_20Thick = 0.144 * inch;
Nut025_20Dia = 0.505 *inch;
Nut025_20Thick = 0.161 * inch;

NEMA17_ShaftDia = 5.0;
NEMA17_ShaftLength = 24.0;
NEMA17_PilotDia = 0.866 * inch;
NEMA17_PilotLength = 0.080 * inch;
NEMA17_BCD = 1.725 * inch;
NEMA17_BoltDia = 3.5;
NEMA17_BoltOC = 1.220 * inch;

    It seems I’m among the few CamelCase holdouts…

  • LTSpice IV: Simulation Run Hotkey

    For some odd reason, Linear Tech’s LTSpice IV simulator has a hotkey to stop a simulation (Ctrl-H), but not one to start the run.

    Add one:

    • Control Panel
    • Drafting Options
    • Hot Keys button
    • Click in Run Simulation slot
    • Tap the ~ key
    • Back out of everything
    LTSPice Run key binding
    LTSPice Run key binding

    Done!

  • VLC Startup Settings: Audio Sync

    While thrashing around with that DVD player, I finally figured out that VLC stores its configuration settings in ~/.config/vlc/vlcrc. I don’t know if it’s supposed to update that file automagically after twiddling the GUI config settings, but it doesn’t; I must manually edit the file to get a sticky change.

    Anyhow, the vital setting for that particular drive turns out to be audio synchronization, as set by the audio-desync parameter. The audio must lag the video by 400 ms, thusly:

    # Audio desynchronization compensation (integer)
audio-desync=-400

    And then it Just Works…

  • Ubuntu 11.10 vs. Epson R380 Printer: FAIL

    After getting everything configured, I hauled the Atom to the Basement Laboratory Computational Center, set the IP address, brought it up as the new file server, backed up the changed files, and everything worked fine. Then I plugged in all three printers, lit up the CUPS configuration screen, and configured the, uh-oh, two printers it could find.

    Turns out that the Epson R380 printer, being a member of the Epson R300 series of printers, doesn’t work with the USB subsystem in Ubuntu 11.10, for reasons that’ll surely get sorted out in a few months. Until then, it’s a showstopper for me.

    So I shut everything down, yanked out the Atom, plugged in the old AMD box, reconnected everything, restored the changed files from backup, and we’re back to where we were a few days ago. I’ll swap in the old drive and slide the Atom underneath the Thing-O-Matic again.

    Drat!

  • NFS V4 Tweaks

    Come to find out that Ubuntu 11.10 uses NFS V4 by default, which means the various clients scattered around here, all of which use NFS V3 by default, report all files have user & group 232 – 2: an awkward and unforgettable unsigned 4294967294. That’s -2 in 2’s complement notation with 32 bit hex numbers, corresponding to the unsigned 16-bit 65534 = -2 for the nobody user & group.

    Fix that by editing /etc/default/nfs-common to set NEED_IDMAPD=yes. Unmount the NFS share, do sudo start idmapd, remount, and it’s all good. The next time the client boots, the idmapd daemon starts automagically, and that’s all good, too.

    Adding the -t nfs4 filetype in /etc/fstab seems to be not necssary.

    How I got into this mess: the Intel Atom D525 that had been driving the Thing-O-Matic has a bog-standard Intel graphics chip that, despite (or perhaps because of) having an open-source video driver, reports doing only OpenGL 1.4. OpenSCAD, however, requires OpenGL 2.0 and those hacks don’t allow it to run properly, which makes it awkward for demos. The AMD that’s currently the file server has, IIRC, better graphics that might improve the situation; I think it sports a somewhat peppier processor, too. The fact that it’s running Ubuntu 8.10 says that it’s time for an update.

    Soooo, I swapped in a new 1.5 TB SATA drive, installed hot-from-the-oven Ubuntu 11.10, replaced Unity with XFCE, inhaled all the current data from the file server’s external USB backup drive, configured ssh / nfs / etc, and I’m now doing some simpleminded tests before I swap the IP addresses.

    Now, if the AMD has craptastic graphics hardware, it’s unhappy dance time…

  • Thing-O-Matic: Small Features

    Strainer - knob perimeter thread
    Strainer – knob perimeter thread

    It seems most of the stuff I build with my Thing-O-Matic involves small features and thin sections that bump hard against the minimum possible sizes. I’ve found that forcing critical solid model dimensions to be integer multiples of the the extrusion width or thickness stabilizes the whole idea→model→G-Code→object chain by encouraging Skeinforge to make the choices I prefer.

    Or perhaps I’m just constraining my choices to make Skeinforge happiest. One can view reality in many ways…

    Anyhow, my OpenSCAD programs tend to have these lines up near the top:

    ThreadThick = 0.33;
ThreadWidth = 2.0 * ThreadThick;

function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

    The ThreadThick parameter matches the Skeinforge thread thickness parameter(s) and the 2.0 matches the w/t setting(s). Those correspond quite closely to the actual printed results, as tediously verified through many measurements. Throughout the rest of the OpenSCAD program, I compute the dimensions of key features using those sizes as building blocks.

    The IntegerMultiple function returns the next higher multiple of the basic Unit that’s greater-than-or-equal-to the desired Size. Feeding in the thread thickness or width as the Unit ensures that the result will be an integer multiple of the smallest-possible dimension and won’t be smaller. The integer limit happens automagically, because the printer can’t lay down anything else, but a less-than-possible size can cause features to (unpredictably, in my experience) vanish without warning. This way your model reflects the printed reality and Skeinforge seems more likely to produce a predictable result.

    So the parameter controlling the thickness of a flat sheet might look like:

    PlateThick = IntegerMultiple(2.0,ThreadThick);

    Given ThreadThick = 0.33, the sheet will be 7 layers thick = 2.31 mm. If the sheet must not exceed 2.0 mm, however, then you need a similar function with floor(), which may eradicate very small features.

    This trick seems most useful for thin wall sections, because the wall width directly affects the fill:

    • Less  than 1 thread width can’t be built
    • Exactly 1 thread width is the thinnest possible wall
    • Widths between 1 and 2 thread widths may be either, depending on surrounding features
    • Exactly 2 thread widths produces a nice wall
    • Widths between 2 and 3 thread widths can’t fill properly
    • Exactly 3 thread widths fills perfectly
    • Over 3 thread widths generally fill properly

    So making the rim around a recessed lid become an integral number of thread widths, with a minimum width of 1.0 mm, looks like this:

    LidMargin = IntegerMultiple(1.0,ThreadWidth);

    With a 0.66 mm thread width, the nominal wall is 1.5 threads wide and could print as either 1 or 2 threads, depending on other factors. Rather than leave the results to chance, I force the solid model wall to be exactly 2 threads wide to make the printed result come out at 1.32 mm. Because I don’t care exactly how wide the lid margin is, as long as it’s at least one thread, that’s fine with me.

    Generally, the values come from computations based on other dimensions, so quantizing the results keeps the printed result stable over small variations of those inputs.

    If I ever get around to changing the nozzle to from 0.5 mm to 0.4 mm, I’ll probably change the thread dimensions to 0.25 mm x 0.5 mm (keeping the same 2.0 w/t ratio). A 1.0 mm wall would then still be exactly 2 threads wide and come out looking exactly the same, but with a total width of 1.00 mm.

    That’s the intent, anyway.