#linuxcnc Logs

Sep 01 2020

#linuxcnc Calendar

03:17 AM Deejay: moin
03:45 AM * Loetmichel likes the 40W laser cutter here, and be it just for cutting intricate shapes into polyester masking tape for powder coating... but i REALLY should remember to put the exhaust hose out the window before cutting... MAAN that "sweet" polyester smell is obnoxious... :-(
03:45 AM Loetmichel: mornin' btw
03:50 AM XXCoder: lol
03:50 AM XXCoder: yo
04:50 AM JT-Cave: morning
05:01 AM XXCoder: morning
05:04 AM JT-Cave: https://dpaste.com/DC7QK9F2U ugly but it works mostly
05:06 AM XXCoder: nice
05:06 AM XXCoder: basicaly it has list of k temperates, and it goes 1 to 100% across each section and "upgrade" or "downgrade" depending on direction
05:07 AM XXCoder: then goes across it, and so on till max or miniu
05:07 AM JT-Cave: each K is a list
05:08 AM JT-Cave: it's a bit clunky atm
05:10 AM XXCoder: if it works and dont waste insane amount of cycles or memory it should be fine
05:25 AM rs[m]1: JT-Cave: you could add linear interpolation between color temperatures ;)
05:26 AM JT-Cave: I think I know what that means... but an example would help a lot
05:27 AM XXCoder: you mean derive a math function out of that?
05:28 AM XXCoder: using some sort of regression
05:28 AM rs[m]1: if if you have interval 21, 35 for K1000, use something like color = ((35-p) * K1000 + (p - 21) * K1500) / (35 - 21)
05:29 AM XXCoder: ah bit simpler than what i was picturing
05:29 AM rs[m]1: this "*" is not meant literally, * in python with lists does something different / not work
06:02 AM JT-Cave: I should cut the string in half and solder the power supply to it as the plug/socket is poor and runs very hot
06:03 AM XXCoder: sounds like not rated for such current
06:03 AM JT-Cave: it's what comes with the power supply
06:04 AM JT-Cave: https://www.amazon.com/gp/product/B07Q26YG61
06:05 AM JT-Cave: the jack adapter
06:05 AM XXCoder: wonder if thats compitable with my micro belt sander and micro lathe
06:05 AM XXCoder: fun
06:15 AM Tom_L: morning
06:15 AM XXCoder: yo
06:23 AM JT-Cave: if it's 5v maybe
06:23 AM XXCoder: i dont remember what volts my stuff is lol
06:26 AM Tom_L: pico has lots of supplies
06:30 AM Tom_L: most are 12v
06:30 AM Tom_L: https://www.mini-box.com/AC-DC-power-supplies
06:34 AM XXCoder: i checked proxxon. pretty cool stuff
06:34 AM XXCoder: that micromill
06:44 AM JT-Cave: https://cdn-shop.adafruit.com/datasheets/APA102.pdf if I'm reading that data sheet correctly the start frame should be 0*32 and the end frame 1*32
06:46 AM rs[m]1: yes, looks like it
06:47 AM rs[m]1: but i'm not sure
06:47 AM JT-Cave: the example I found footer = [0, ] * math.ceil(numLeds / 16.0) seems to be wrong then
06:47 AM rs[m]1: why would it need an "end" frame?
06:47 AM JT-Cave: no clues here
06:47 AM rs[m]1: ?
06:48 AM JT-Cave: I do know if the end frame is not long enough the last lights won't come on
06:48 AM rs[m]1: [0, ] * n becomes [0, 0, 0, ... 0] with n elements
06:50 AM JT-Cave: yeah the result of having 240 leds is [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
06:52 AM rs[m]1: I'm too stupid for this kind of datasheet
06:54 AM rs[m]1: the end frame is just [255,255,255,255], isn't it?
06:55 AM rs[m]1: but it is kinda ambigous, because [255, 255, 255, 255] is a valid dataframe that should turn on everything with full current
06:55 AM rs[m]1: s/everything/every color/
06:58 AM rs[m]1: how does the chup know when to latch current shift register output into the pwm generator?
06:58 AM rs[m]1: chip
07:02 AM rs[m]1: JT-Cave: you know https://github.com/adafruit/Adafruit_CircuitPython_DotStar ?
07:24 AM Tom_L: spi?
07:25 AM Tom_L: you need to shift out the last byte.. does end frame do that?
07:27 AM Tom_L: iirc slave is always behind master by 1 shift
07:28 AM Tom_L: JT-Cave, ^^
07:48 AM JT-Cave: rs[m]1, yes I have that library but prefer not to use it as it is a bit flaky
07:48 AM JT-Cave: Tom_L, not sure what you mean
07:48 AM JT-Cave: yes SPI
07:48 AM * JT-Cave heads to the shower after being a Chicken Tender for the last hour
07:49 AM rs[m]1: JT-Cave: the documentation in the datasheet is not sufficient
07:49 AM rs[m]1: something else has to be going on
07:50 AM rs[m]1: (something timing related probably) - because there seems to be no clear trigger to latch shift registers into PWM
07:51 AM rs[m]1: the adafruit lib suggests some sort of variable-length footer is needed with one 1 bit for every 2 LEDs
07:51 AM rs[m]1: rounded up to multiple of 16 or something like that
07:54 AM rs[m]1: but that doesn't really make sense IMHO
08:05 AM JT-Cave: there is also a fastled lib for the ardunio
08:07 AM JT-Cave: https://github.com/adafruit/Adafruit_DotStar/blob/master/Adafruit_DotStar.cpp
08:17 AM JT-Cave: https://cpldcpu.files.wordpress.com/2014/08/apa-102-super-led-specifications-2013-en.pdf
08:49 AM jymmmm: JT got a new project for ya... Jumbo gantry, meet jumbo vise... https://www.youtube.com/watch?v=gFrhwC0eeCs
09:12 AM * JT-Shop doesn't watch videos that start out with a smiling hand waving person lol
09:13 AM jymmmm: smiling hand? lol, IDK bout that, but a 1200 lb vise with 40 tons of pressure sounds up your alley
09:14 AM jymmmm: It's the same guy that did the 120MPH belt sander, and has that fricken awesome cincinati shaper
09:16 AM jymmmm: That thing just eats metal for a snack
09:17 AM rs[m]1: JT-Cave: that PDF is the same gibberish
09:18 AM roycroft: my belt grinder maxes out at ~53mph, and it's more than fast enough for anything i need to do
09:18 AM roycroft: i can't imagine running it twice as fast
09:20 AM SpeedEvil is now known as Guest33892
09:28 AM rs[m]1: JT-Cave: look at comment by "Bernd Walter"
09:28 AM rs[m]1: JT-Cave: it explains how it works
09:32 AM seb_kuzminsky: linuxcnc-build: force build --branch=2.8 --revision=v2.8.0 0000.checkin
09:53 AM jymmmm: WTF?! What manufacture would have a datasheet for their crimp terminals but NOT include electrical ratings?! https://www.te.com/usa-en/product-32996.datasheet.pdf
09:56 AM solobolo2 is now known as htasta
10:00 AM rs[m]1: funny that 8AWG is approx. 8mm²
10:08 AM Rab: jymmmm, very strange. I found a mechanical drawing, but it doesn't list current capacity (or voltage) either: https://www.alliedelec.com/m/d/dc707b81c66da5c1f211b43bde2e4eeb.pdf
10:08 AM jymmmm: Rab: Yeah, all kinds of mechanical drawings, but ZERO electrical specs
10:09 AM Rab: I guess you are to assume it meets or exceeds the ampacity of 8AWG wire?
10:10 AM jymmmm: Rab: They say "heavy duty: no", so I'm not gonna speculate that
10:10 AM Rab: hah
10:27 AM JT-Shop: rs[m]1, comment where?
10:28 AM rs[m]1: JT-Shop https://cpldcpu.wordpress.com/2014/08/27/apa102/
10:30 AM JT-Shop: if you said something in the last half hour I missed it due to a drop or three of rain killing my connection
10:31 AM rs[m]1: so basically, what seems to happen is that the apa02 waits for a sequence of zeros, and after that latches the next 4 bytes that start with "111" into its pwm registers and then it forwards received bits onto its output
10:32 AM JT-Shop: ah ok that makes sense
10:35 AM rs[m]1: footer frame is there to make sure everything is flushed out properly, and has to contain at least n / 2 1-bits
10:35 AM JT-Shop: ok
10:35 AM rs[m]1: that is ceil(n/2)
10:39 AM JT-Shop: yeah I figured that one :)
10:44 AM JT-Shop: But the one pattern is required for the LEDs to shift the filtered data stream to the next LED.
10:44 AM JT-Shop: Each LED needs an additional half clock cycle for filtering the data.
10:44 AM JT-Shop: 2 and 3 LEDs need an additonal ones, 100 and 101 LEDs need 50 additional ones clocked.
10:44 AM JT-Shop: More ones clocked won’t matter, but the 32 bit in the datasheet only works for up to 65 LEDs.
10:44 AM JT-Shop: In a workload with regular updates you might not notice, because the next update will clock out the previous data to the remaining LED.
11:00 AM Deejay: re
11:34 AM JT-Shop: yea last part is done in the vmc
12:06 PM JT-Cave: so even if I only are working with 5 leds in the string of 240 the footer needs to be for 240???
12:18 PM Tom_L: JT-Cave, https://www.analog.com/media/en/analog-dialogue/volume-52/number-3/introduction-to-spi-interface.pdf
12:18 PM Tom_L: look on P3 at the data flow
12:19 PM Tom_L: slave lags the master by a byte so you gotta shift an extra byte to get the last one
12:21 PM Tom_L: that was my point earlier
12:47 PM -!- #linuxcnc mode set to +v by hitchcock.freenode.net
02:34 PM JT-Cave: Tom_L, that's not how the apa102 works, they are data in data out to next chip
02:35 PM JT-Cave: https://cpldcpu.wordpress.com/2014/11/30/understanding-the-apa102-superled/
02:35 PM JT-Cave: The APA102 receives a valid SPI signal and outputs a valid SPI signal to the next devices.
02:36 PM JT-Cave: the only function of the “End frame” is to supply more clock pulses to the string until the data has permeated to the last LED
02:42 PM rs[m]1: the apa02 doesn't work like a bucket brigade
02:43 PM rs[m]1: it waits for start sequence (0s), then eats the next 4 bytes while outputing 0s
02:43 PM rs[m]1: after that input is copied to output with half a clock delay (?) or something like that
02:44 PM rs[m]1: also, there is no such thing as "standard" spi
02:45 PM rs[m]1: (what i meant is there is no single SPI standard as in normative document)
03:00 PM Deejay: gn8
03:21 PM CaptHindsight: here's the standard for SPI: SPI has a 4-wire synchronous serial interface, the rest is up to you
03:22 PM Tom_L: yeah, phase and polarity are all over the place
03:23 PM Tom_L: and clock..
03:24 PM CaptHindsight: you may also see these signals associated with SPI or not: MOSI MISO SCK CSB
03:24 PM Tom_L: CSB?
03:24 PM Tom_L: oh chip select
03:24 PM CaptHindsight: https://www.mouser.com/pdfdocs/tn15_spi_interface_specification.PDF
03:25 PM CaptHindsight: might be CS or similar
03:25 PM Tom_L: bud's got a bad uart on his cnc motherboard. sent it in and it came back still broke
03:25 PM CaptHindsight: SS
03:25 PM Tom_L: $1k later
03:25 PM CaptHindsight: slave select
03:25 PM Tom_L: bastards
03:26 PM Tom_L: it's that or a broken wire somewhere
03:26 PM rs[m]1: most of the time you can get away with MOSI, MISO and clock
03:27 PM Tom_L: yeah, gnd the cs on the slave
03:27 PM Tom_L: or + whichever...
03:27 PM rs[m]1: but some kind of reset doesn't hurt in case there are framing errors
03:27 PM JT-Shop: with apa102 you only have clock and data in
03:28 PM Tom_L: hardly sounds like spi
03:28 PM Tom_L: sounds more like i2c
03:30 PM rs[m]1: i2c is an actual standard, and is much more complicated
03:54 PM CaptHindsight: know anyone that CNC polishers injection molds?
03:55 PM CaptHindsight: heh polishes
03:55 PM CaptHindsight: https://www.youtube.com/watch?v=uAami28gPbU
03:56 PM Tom_L: not around here
03:56 PM Tom_L: no money in... wax on -- wax off
03:58 PM Tom_L: pretty cool though
03:58 PM CaptHindsight: I don't think anyone polishes resin molds anyway, so that would be in-house until somebody else copies my idea again
03:59 PM CaptHindsight: DLP print composite resin mold, polish to mirror finish, inject a few 100's
04:00 PM Tom_L: just use a waterpik :)
04:01 PM CaptHindsight: Tom_L: tell me about this waterpic idea?
04:01 PM Tom_L: toothbrush
04:01 PM CaptHindsight: don't see the fit except maybe on an outside edge
04:02 PM CaptHindsight: CNC toothbrush sure
04:03 PM Tom_L: are the fibers abrasive or is the abrasive added in?
04:03 PM CaptHindsight: whatever works
04:04 PM CaptHindsight: injection molds with resin have high amounts of aluminum powder
04:04 PM CaptHindsight: well can have
04:52 PM zipper is now known as Guest63345
05:25 PM Loetmichel: hmm, question: (i am just writing a fantasy story) Whats the rooling bed called in english thats used in hospitals to move patients around?
05:25 PM Loetmichel: (quite the challenge to write novels in a language that not your mother tounge btw ;)
05:30 PM CaptHindsight: Loetmichel: possible a Gurney
05:32 PM CaptHindsight: Krankenhaus rollendes Bett
05:40 PM Loetmichel: CaptHindsight: yes, got that. thanks.
07:10 PM zipper is now known as Guest51495
08:23 PM CaptHindsight: https://www.youtube.com/watch?v=KZ_w7O8bjRk safe in the vise?
08:24 PM XXCoder: for some definition of "safe" maybe
08:38 PM Tom_L: they look like professionals i'm sure it's safe
09:01 PM FinboySlick: It's super-safe, he even put on his mask to protect himself from all the COVID the fan was pushing his way.
09:02 PM XXCoder: its smartest thing that guy did
09:04 PM roycroft: root@vm1:~# pveversion
09:04 PM roycroft: pve-manager/6.1-7/13e58d5e (running kernel: 5.3.18-1-pve)
09:04 PM roycroft: ack
09:04 PM roycroft: mischan
09:19 PM CaptHindsight: anyone know the typical fittings and size used for co2/n2 supply in paintnball guns
09:20 PM Tom_L: https://www.ansgear.com/Paintball_Fittings_Hoses_s/118.htm
09:21 PM Tom_L: https://www.ansgear.com/CO2_Vs_Compressed_Air_s/4835.htm
09:23 PM CaptHindsight: some say 1/8" NPT
09:23 PM CaptHindsight: some don't say at all
09:23 PM Tom_L: saw that
09:23 PM CaptHindsight: https://www.ansgear.com/Straight_Macroline_Fitting_p/macrofittingstraight.htm
09:23 PM Tom_L: https://www.paintball-parts.com/Air-Fittings-s/12.htm
09:24 PM CaptHindsight: somewhere 1/4 to 1/8 NPT
09:25 PM CaptHindsight: and then there are SCUBA adapters
09:25 PM Tom_L: https://www.astm.org/Standards/F1750.htm
09:26 PM Tom_L: there's your official answer
09:26 PM CaptHindsight: not really
09:26 PM CaptHindsight: since different vendors have different plumbing setups
09:27 PM Tom_L: i would think it to be convered there
09:30 PM Tom_L: a high percentage of them look like npt
09:30 PM Tom_L: and purposely oddball designed quick connects
09:32 PM CaptHindsight: yeah those are ones that i was looking at, the odd ones
09:33 PM CaptHindsight: I bet most of the plumbing is NPT and then they go "custom" for their quick connect at the gun to tie you into their accessories
09:33 PM Tom_L: possibly
09:59 PM CaptHindsight: IL has odd laws around what is and what is not a firearm
09:59 PM CaptHindsight: odd compared with most other states
10:00 PM FinboySlick: In Canada, I think anything that sends a projectile past a certain speed counts as 'firearm'.
10:01 PM CaptHindsight: similar in IL has to be under 700fps
10:01 PM CaptHindsight: which is ~450mph
10:02 PM CaptHindsight: or under .18 inch dia
10:02 PM XXCoder: so bow and arrow counts as gunm
10:02 PM XXCoder: *firearm
10:03 PM CaptHindsight: Illinois excludes from the definition of firearms any pneumatic gun, spring gun, paint ball gun, or B-B gun which expels a single globular projectile
10:03 PM CaptHindsight: not exceeding .18 inch in diameter or which has a maximum muzzle velocity of less than 700 feet per second or which expels breakable paint balls containing washable marking colors.
10:04 PM CaptHindsight: crossbow is probably defined in some other section
10:04 PM FinboySlick: Um... So if you send a 0.17" diameter slug at 1000 feet per second, it's not a firearm?
10:05 PM CaptHindsight: likely not but I'd have to find the full code section vs this summary
10:05 PM FinboySlick: They'll need railgun provisions soon ;)
10:05 PM XXCoder: firearm https://s3.amazonaws.com/lowres.cartoonstock.com/dating-caveman-neanderthal-woos-flowers-firearms-nki0211_low.jpg
10:06 PM XXCoder: sadly author sold all comics to cartoonstock. no more nice pictures
10:06 PM CaptHindsight: llinois law defines “air rifle” to: (any implement that is not a firearm which impels a breakable paintball containing washable marking colors or, a pellet constructed of hard plastic, steel, lead, or other hard materials with force that reasonably is expected to cause bodily harm.)
10:07 PM CaptHindsight: so air rifles here have their own regulations, not firearms and not completely unregulated
10:07 PM CaptHindsight: not allowed to <13
10:08 PM XXCoder: i find it funny that its harder to buy beer than a rifle in some states
10:09 PM CaptHindsight: well beer is evil
10:09 PM CaptHindsight: have the puritans ever been against guns?
10:09 PM XXCoder: dunno
10:09 PM CaptHindsight: only feeling good I think
10:10 PM CaptHindsight: if guns make you feel too god they will be against those as well
10:10 PM XXCoder: yeah virtually anything feel good is a sin
10:10 PM CaptHindsight: god/good
10:10 PM XXCoder: god works too lol too godlike persona
10:10 PM CaptHindsight: the miserable puritans
10:11 PM CaptHindsight: FinboySlick: Hawaii has rail guns laws
10:11 PM CaptHindsight: “Electric gun” is defined under state law to mean “any portable device that is electrically operated to project a missile or electromotive force.”
10:34 PM CaptHindsight: https://arstechnica.com/science/2020/09/first-modular-nuclear-reactor-design-certified-in-the-us/
10:36 PM CaptHindsight: XXCoder: https://www.nuscalepower.com/about-us/history
10:37 PM CaptHindsight: your backyard
10:38 PM XXCoder: looking
10:42 PM XXCoder: definitely interesting
10:42 PM XXCoder: though no update for 2 years
10:45 PM CaptHindsight: XXCoder: the link above that one
10:45 PM CaptHindsight: they just got approval
10:45 PM XXCoder: oh
10:46 PM XXCoder: interesting
10:57 PM CaptHindsight: https://www.the-scientist.com/news-opinion/is-a-bradykinin-storm-brewing-in-covid-19--67876
11:06 PM XXCoder: cant even follow that lol
11:08 PM CaptHindsight: XXCoder: we might be able to block the inflammation that some people have when fighting covid-19
11:10 PM CaptHindsight: finding from research in the netherlands and what a supercomputer helped discover
11:11 PM CaptHindsight: so it won't be as deadly to some
11:12 PM XXCoder: nice!
11:12 PM XXCoder: since covid may well be around forever after this that will save lot lives
11:15 PM CaptHindsight: research like this gets down to the actual nuts and bolts of the immune system vs just it's broken
11:16 PM CaptHindsight: "van de Veerdonk recognizes that peptide levels need to be measured and is currently setting up mass spectrometry to measure kinins in the plasma, which have a half-life in plasma of just a few seconds
11:17 PM CaptHindsight: so you have to detect the levels of something that is only there for a few seconds
11:18 PM CaptHindsight: why things like nanobots that measure chem levels like this would be handy
11:18 PM XXCoder: indeed
11:18 PM XXCoder: but then if we had nanobots like that it'd directly kill viruses thats not in authorized list
11:19 PM CaptHindsight: thats another jump, initially it would help if they just did some very basic things
11:20 PM CaptHindsight: like identify some condition and report back vs fight a war
11:20 PM CaptHindsight: spotter vs army
11:20 PM XXCoder: true
11:22 PM CaptHindsight: imagine a few decades of real diagnostics in vivo (within a cell)
11:23 PM CaptHindsight: then we can put all the pieces together
11:23 PM CaptHindsight: and if assholes don't control it all
11:24 PM skunkworks: on a side note.. The techs are going gaga over the new nvidia video cards..
11:25 PM XXCoder: i dont know if nanomachines is ever workable