$0.99 calculator from any gas station?
tomp is now known as tomp4
3 days ago, someone mentioned a bit of software that used the parallel port to make a SPI interface. Does anyone know where to find that? I looked through LinuxCNC.org, and couldn't find anything.
tomp is now known as tomp4
GoSlowJimbo: get a google search on your browser, click the options or advanced button. tell it to find SPI and tell it to search the irc site www.linuxcnc.org/irc/irc.freenode.net:6667/emc .
this will find all the irc discussion log entries with SPI.
you can also learn to do this from the url field w/o the advanced search form.
cradek or jepler told us this trick
the above , typed into the google search field, will get you loads of hits
oh, beware, the search rtns the .txt AND the .rdf variants of the log. the rdf is not nice to read
supply of parts for someone in the states ebay 190307928063
[15:19:05] <pcw> http://www.youtube.com/watch?v=a1ThSi1wbqU&feature=player_embedded
steves_logging is now known as steve_stallings
cradek: the problem with axis I had yesterday I think it is this old slow computer of mine if I limit what I am doing and load the part program before I come out of estop on a fresh axis load it works fine, 566 celron ,just letting you know ,thanks for the look see! and the rest of you too!
alSMT: hmm, I think I've seen it freak out on very slow computers. I bet that's part of the cause.
steve_stallings is now known as steves_logging
Hi, I have been gathering some infos these days around EMC
and started to translate some pages of the website in french
Where should I send them or to whom?
send them to the developers mailing list
kind of quiet around here
Everybody's EMC must be running flawlessly
heh heh heh...
mine is undergoing an extension
I'm currently building a CNC router machine and I'm exploring software options
stepper or servo ?
I'm using the JGRO plans from CNCZone
I use steppers for my plasma cutter
Im adding a 5th stepper today
I'm figuring this as a first build....
what kind of drivers?
As I build I already see changes I want to incorporate into build 2
what are you working on archivist ?
original fugly homebrew mill
got any pics?
gotta run... back later
BigJohnT_ is now known as BigJohnT
my new EMC project :D
[19:57:20] <colin__> http://img.photobucket.com/albums/v280/rallyslag/5axismill.jpg
that could be fun
should be :)
thinking of using AC servo motors
not decided what to do about the leadscrew backlash yet
it has linear scales on
whether using linear and rotary encoders can work nicely enough together to compensate
cost of fixing the backlash :((
I run my machine in one direction to get round
yeah it will be a pain
tho using the linear encoders should help
doenst have to run any mega fast feedrates anyway
might be worth sorting out the screws for something a bit more accurate tho
doubt they will be cheap due to size tho
you can compensate
i will try first
but servos and backlash wont be funny
linear scales + servos + backslash
I think you better re-think that approach unless you have very good screws
or have rotary encoders on the servos(in case it dosent work as you like it)
you should be able to compensate for the backlash by profiling the screws. Compare expected position to actual over the length of the screws with your range of loads
i think ill check out the screws and see if i can solve the backlash
the motors will have rotary encoders anyway
you could always do away with the screws and use linear motors, if you don't mind the cost :)
i think this machine is a bit too big and heavy for linear motors
would probably be better getting some good quality ballscrews and nuts
what are the loads?
dont really know exact figures
[20:29:30] <colin__> http://img.photobucket.com/albums/v280/rallyslag/5axismill.jpg
but thats the machine
the y is ok as its counterbalanced, and the z is the spindle in and out
and x doest feel that heavy when manually winding
you're not going to move it too fast then
dont need to anyway, spindle speed isnt that high anyway
just fyi, linear servo motor example 955N continuous http://www.aerotech.com/products/motors/blmx.html
more for taking slow deep cuts
how does emc like working with linears ?
L84Supper: cute, but what do they cost?
depends of your pocketbook :)
i did think about building a machine a while back using a granite table
using airbearings and a linear motor
[20:38:02] <L84Supper> http://cgi.ebay.com/AEROTECH-ABL20060-LINEAR-AIR-BEARING-STAGE-MOTOR-WOW_W0QQitemZ360151055350QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item53daacfbf6&_trksid=p3286.c0.m14&_trkparms=72%3A1205|66%3A2|65%3A12|39%3A1|240%3A1318|301%3A1|293%3A2|294%3A50
hm, for 5000 you can buy a used machine already made..
they dont look ok for machine tool work
yeah, you don't need 1 micron res
yeah a bit much
I bet you can profile your screws down to a few microns
I did score a new proper ballscrew on ebay
[20:41:03] <colin__> http://www.newwayairbearings.com/Dovetail-Air-Slides
recalibrate the screws every month or so
probably not neccesary tho
i do think using linear encoders along with the rotarys on a fairly tight system should be accurate enough
I'm using EMC2 in the design of a new digital web press, servos, tension control, head positioning etc.
cradek, yeah iv seen that thanks :)
ok, just checking, that was one successful experiment with dual feedback
the linear encoders will give to actual position, and your rotary encoders will give you what the motors actually did
would it be better to setup the servos with a driver that handles the encoder to the motor itself
then have emc have backlash settings and use the linears as a check the ferror
exactly, since you have both you'll be able to check
hmm could work best as the motor then wont be hunting each side of the backlash to make the linears move
if you rely on the rotary encoders only and the lash changes you won't find out until you check your parts
well if i use a drive that takes step/dir
emc can be setup just like a stepper system
but with the linears to check the error
and just set the backlash in emc
least then it would stop things if the error was too high
i may well still see about new ball screws
depends on cost
least if i can rig it to work for now ill be happy
I don't use screws much myself since we tend to be working with things that move all the time, we'd wear out most screws in days or weeks
i guess it depends on speed and load aswell
with decent ground ballscrews i bet this machine could run for 20yrs without problems
yeah, your feeds rates are probably in the fractions of an inch per second
probably about 2000mm/min
I'm working on some now that move at 1000mm/sec with accel and decell at 1-2G
thats pretty quick
id love to build a little high speed mill one day
gantry with only 10Kg load, +/- 50 micron repeatability
think most of my tooling has a higher run out than that lol
yeah, these are >$100K with a 1.5m x 3m bed
what are they for ?
mostly for printing electronics, solar cells, OLED displays, etc.
ah i see
think my next project is robotic arms
already aquired a cheap little one with ac servo motors
gonna test out the kine on that, then look at getting a big ABB bot
ABB is pretty free with their specs and manuals
just not for their software
what kind of bearings do they use ?
in your printers
air and linear
well, air and magnetic
do air bearings work well at high speed then ?
for linear at 2 meters/sec and rotary at 22,000 rpm
we use the rotary air bearings for laser scanners
thats pretty quick
how do they handle load?
works for us, iirc the rotary handles a few Kg at 22K/rpm
i bet encoder counting must be an issue at your feedrates ?
not with an fpga
we can count and process faster than we could ever move
i have some mesa boards for my mills
not sure what the max encoder count is on them tho
if you count in hardware >100MHz
iirc the fpga's in the Mesa can probably handle inputs to 200MHz
what sort of mhz are the fpa you use?
the <$100 Altera or Xilinx are 200Mhz
so the mesa is fairly capable aswell then
[21:38:01] <L84Supper> http://flash-plaice.wikispaces.com/
here' a logic analyzer we started working on
whatever it does :)
sounds similar to http://www.sump.org/projects/analyzer/
captures digital signals, puts them up on the screen for analysis
(that one's not flash programmer or ice though)
we started adding on to the sump project
sounds like a very sensible approach to me
was mainly for emulating flash in circuit for open source bios development
coreboot for x86 and uboot for risc
I have an s3board with sump.org's la installed on it, but I don't use it as much as I expected to
trying to get to the point of a complete open source machine controller
firmware, OS and applications
will it run emc :P
I just don't get the wide use of XP in machine control, I always ask where the reset button is for when it hangs
"XP for killer robots"
we have EMC running on some mini-itx VIA boards C7 +cn700 chipset
tbh most of my emc systems are just old hardware iv found laying around
benchmarking now to see what we can really do, coreboot + Linux + EMC
~$120 for 1.5GHz C7 + 1GB DDR2, unichrome graphics are a bit of a pain
[21:53:16] <L84Supper> http://www.via.com.tw/en/products/mainboards/motherboards.jsp?motherboard_id=490
unichrome is integrated into the northbridge
runs the speed of a decent ATI gpu from 6 years ago
we will try some AMD 690/600 as well in mini-itx
so whats the advantage of coreboot?
open source BIOS, fast boots , 5 sec from power on to login
we should be in the 2-3 sec. max range with a bit more tweaking to Debian
that must be pretty stripped down almose useless kernel tho ?
or can it load up X and emc pretty quick aswell ?
yes, 5 sec with X, power-on to X login
so where does it load it all from ?
you can have a kernel in flash along with firmware
then just load X and whatever from a drive?
yes, you have to wait for the drive to spin up
kexec lets you swap kernels without reboot as well
could probably just load the rest from a usb key pretty quickly then ?
yes, ~1 sec for coreboot + kernel in flash, then EHCI in kernel to load from Flash drive
Phoenix just started copying us again, kernel + BIOS in flash
[22:07:29] <L84Supper> http://linux.slashdot.org/article.pl?sid=09/05/14/2254252&from=rss
[22:08:20] <L84Supper> http://www.technologyreview.com/computing/22643/
think for what i have planned
i might just setup emc in dsl or puppy linux
we are doing it with debian
somebody here was working with Arch
was working on getting EMC on Ubuntu 9.04
i am hoping to build emc into a plug and go system for something
so keeping it minimal is best
rtai_shm wasn't found or something error
Ubuntu , ugh
that C7 mini itx board looks really nice
if VIA can stay solvent
[22:16:18] <L84Supper> http://wwwd.amd.com/catalog/salescat.nsf/doclookupweb/C535EA5BBC2201BC862572BB002ECA24?OpenDocument&id=WinMate+Communication+INC.+~A270+Mini-ITX+Industrial+Motherboard
supports dual core X2 with 690/600 chipset
[22:19:57] <L84Supper> http://wwwd.amd.com/catalog/SalesCat.nsf/doclookupweb/5B08DE8F63A45F3F862572BC001ED692?OpenDocument&id=IEI+Technology+Corp.~KINO-690S1
the little C7 board is probably more than enough tho
[22:20:34] <L84Supper> http://wwwd.amd.com/catalog/SalesCat.nsf/doclookupweb/061E74F713F701688625730D00106818?OpenDocument&id=MSI~Fuzzy+RS690T
sure, but incase you need more cpu or graphics, the 690/600 is supported by coreboot
colour gfx would be nice
we did some flight simulator game to run ok on the VIA vb7001
DVD playback is only on 5% of the cpu with tweaks to VLC
well i only want it to run emc
attach via a usb mesa board
the driver devs at VIA don't know Linux well
it does have a single PCI slot but there is a dual PCI riser with extra INT's
EMC over USB is limited to the latency of the isochronus transfers
going to see how fast we can get it going
you might not be able to control a high speed spindle, but it may work well enough for many apps
well i need to control a minimum of 6 motors
with encoder feedback
your rates may be slow enough
this is for a robotic arm
so still not going to be super fast compared to your application
plus if you are using a small distro with only EMC running, no backgound services or sharing of the USB
according to the Linux kernel doc "Log2 of default interrupt delay, in microframes. The default
107value is 0, indicating 1 microframe (125 usec). Maximum value
108is 6, indicating 2^6 = 64 microframes. This controls how often
109the EHCI controller can issue interrupts.
meaning what ?
EMC over EHCI USB, 125 usec would be the min. time between interrupts
if you need anything services faster , it won't work
would i be better with a pci mesa board ?
yes, PCI irq's are faster
125 usec = 8000 irq's per second
USB = Ugly sluggish bus
the neat thing about choosing a pci or epp board over a usb solution is that it exists
and there's a driver for it
and a maintainer
and a company behind the boards
yeah, we looked at a usb driver for this, no real need so far
also, it works
can't think of any drawbacks actually :-)
pci is fine :)
cradek: maybe some might say it's uncool :P
less plug& play
although for a mill that's rubbish
maybe there is a need now for some PCIe fpga boards for EMC
|oi ,<--- which wire is 'hot'?
cradek: Hey there's another guy named cradek over on the #beagle channel!
I think mesa is working on pcie boards
mshaver: funny that
Alex, did anyone get a pre-compiled 2.3.0 sim made yet - I'm rpl my laptop SSD and figured I'd use the latest if its available?
I hear he's a big jerk
Skullworks: sim is there for 2.3.0
Skullworks: it's in the repositories
wow, the user map is getting fuller
cool - wiki still only listed the 2.8 which I had - I'll update the Wiki after I get it successfully installed.
Skullworks: 2.2.8 I hope ;)
cradek: yeah, but also spammier some times
running on 8.10 works for tk but not axis
alex_joni: oh do you have to keep cleaning it up?
but for testing errors in the G-code it does just fine
I do it from time to time
if i want to electrocute myself with a regular 120VAC outlet in the USA, do i have to connect myself to both vertical pins?
I don't really understand why spammers go through the extra trouble
they need a valid email, and verify the new account, etc
maddash: no, one will do
then they appear on the map, with a link to the profile, where they have a link to some pammy page
maddash: but I suggest you try it both ways to be sure
cradek: which one?
maddash: either you connect to both
or you connect to gnd and only one
the small one may work better
but then you have a 50%-50% chance
a backfeeding neutral can really wake you up too.
alex_joni: but bottom line is that i have to touch at least two of the three (two vertical, one circle) pins, right?
wait a second
no, sometimes it's enough to touch one
if gnd closes through you and where you are standing
Depends on how well you are grounded
if you have rubber shoes, then touching any one should be fairly non-deadly
if i"m sitting in a tub full of water, which wire do I touch? the larger?
maddash: probably any is just as fine :D
take a switch that goes to a lightbulb, then it's surely fine whatever you touch
how can that be? i wouldn't be closing the circuit
you'll end up under water anyway
if you are in water you are closing it
water is connected to gnd through the drains
right, but the generator at the power plant isn't connected to the ground
what about PVC waste lines?
L84Supper: there it might be different
maddash: actually, if it's a fairly new outlet, and wired correctly, the shorter of the two vertical slots is "line", the taller one is "neutral" which is connected to "ground" (PE to the EU folks) in the fuse box.
i.e., the smaller pin in my AC outlet is connected to the "-" end of the generator, and the larger pin is connected to the + end of the generator
usually neutral and gnd (PE) have a very similar potential
if you have a good PE connection, and no differential breaker then you can run some appliances on line and gnd/PE
mshaver: it's quite common in factories around here to wire neutral and PE together, and only use lines for "line's"
in the US there are two "line" wires, each is 120Vac away from ground, and they are 180 degrees out of phase, thus there is 240Vac from line to line.
mshaver: exactly! so since I live in NY, I'd have to touch both line wires to off myself, right?
we have usually neutral, 3 * line and PE
together at the fuse box, or do they use PE to return load current as well
maddash: anything about 50V or so can be deadly
i have 120/208 wye
if you stick an electrode inside your skin, you can die by 9V or less
mshaver: so you use both lines in a house installation?
to separate the load?
brb, going to try this out
maddash: use a voltmeter first
maddash: not really. If you touch the short slot (line) and you are also touching a metal plumbing fixture that is grounded (typical), then the "line" current will return via the grounded plumbing.
tomp is now known as tomp4
also, almost all electrical devices with a metal frame are connected to PW
so touching that and a line should be just as bad
if your power cord is three prong and your outlet is only two prong, should I clip off the ground pin or rewire the house?
alex_joni: yes, the input from the power company to a house is a center tapped transformer secondary. The center tap is called neutral and is tied to earth ground via a rod driven into the ground.
the secondary voltage is about 230Vac
although Ive seen 219 and 247
Everywhere else in the world (except Liberia I think) you have 220Vac and one side of this circuit is attached to earth somewhere, sometimes at the building it's entering and sometimes at the power station as I understand it.
it's 230VAC in europe now
and 400V for 3-phase, instead of 380V a couple years ago
So, I see equipment (single phase) with the wires labeled L, N, and PE. The problem comes in when we hook it up and the "N" wire is 120Vac away from PE.
what is l to pe?
then L to N is 0 or 240?
l to n, if it's a 240V machine from the EU is 240
US built machines can have 4 wires in a single phase setup: L1, L2, N, and GND(PE)
physical earth, yep
One advantage is that since L1 and L2 are 180 degrees out of phase you can return all the 120 load current from both L1 and L2 via a single neutral wire.
mshaver: yeah, but on equipment with L,N and PE, it should be safe to connect things where N and PE are different
PE only goes to the exterior of the equipment
and N is for neutral
* alex_joni heads to bed though
good night all
alex_joni: true, it's more of a labeling thing
rockwell/allen bradley ~(not aquote) neutral is a reference point, not meant to carry any current except mistakes. gnd is a current path fro when insulation fails http://www.ab.com/drives/techpapers/rfignds.htm
nifty - using the 2.3-sim.deb Axis works in 8.10 - sim 2.2.8 Axis didn't play well with the updated file versions.
this neutral ground has lotsa opinions, another src sez neutral always carry current, and gnd is a safety return that fuses can use ( fuses from line to gnd??!!) http://www.askmehelpdesk.com/electrical-lighting/ground-bar-vs-neutral-bar-111142.html
gnd is safety and fault path it must remain intact to blow fuses
UK specs for gnd wire has become insane
If neutral and Gnd are connected... then you can check insulation by... "For measuring an insulating fault, you loose the screw and measure the resistance between N and PE. Normally it should be very high, several Mohms or infinite." (get a 'megger' to check this )
the screw refered too connects gnd and neutral
dinner, bye for now
is this thing on?
This will turn some heads - running sim on my EeePC - The ultimate in backplot software - Testing you G-Code on the real control app.