Re: [Emc-users] New kind of stepper motor on eBay

[Gene Heskett]

On Sunday 28 May 2017 01:44:20 Erik Christiansen wrote:

> On 28.05.17 01:05, Gene Heskett wrote:
> > On Saturday 27 May 2017 23:58:14 Erik Christiansen wrote:
> > > P.S. As a side issue, I couldn't remember the imperial g, but:
> > > You have: gravity
> > > You want: ft/s^2
> > > * 32.174049
> > > / 0.03108095
> > >
> > > Yes, now I remember using 32, back as a schoolkid, before we went
> > > metric.
> >
> > Thats all we had when I was in school, in the '40's. The only
> > metrics I was exposed to then was in my electronics stuff as I
> > learned it, beginning also in the '40's while WW-II was in full
> > swing. :) Theres been a whole lot of water under the bridge since
> > then.
>
> Yup, if you said today "Don't hide your light under a bushel.", the
> literal part of the analogue would probably no longer be recognised
> as a candle put under an upturned 35 litre wooden measuring bucket.
>
> Erik

It would at least require an explanation for any one under 30 unless they 
are a regular church attendee.  It been that long since I heard 
reference to it, and that came from the back side of a pulpit.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] New kind of stepper motor on eBay

[Erik Christiansen]

On 28.05.17 01:05, Gene Heskett wrote:
> On Saturday 27 May 2017 23:58:14 Erik Christiansen wrote:
> > P.S. As a side issue, I couldn't remember the imperial g, but:
> > You have: gravity
> > You want: ft/s^2
> > * 32.174049
> > / 0.03108095
> >
> > Yes, now I remember using 32, back as a schoolkid, before we went
> > metric.
> >
> Thats all we had when I was in school, in the '40's. The only metrics I 
> was exposed to then was in my electronics stuff as I learned it, 
> beginning also in the '40's while WW-II was in full swing. :) Theres 
> been a whole lot of water under the bridge since then.

Yup, if you said today "Don't hide your light under a bushel.", the
literal part of the analogue would probably no longer be recognised
as a candle put under an upturned 35 litre wooden measuring bucket.

Erik

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Re: [Emc-users] New kind of stepper motor on eBay

[Gene Heskett]

On Saturday 27 May 2017 23:58:14 Erik Christiansen wrote:

> On 27.05.17 16:58, Gene Heskett wrote:
> > I think so too.  But I am so used to thinking in in/lbs, and have
> > never seen a formula or a chart that converts Nm to in/lbs,
>
> But on just about any full linux distro under your roof, you have:
>
> $ units
> You have: 3 N m
> You want: lbf in
> * 26.552237
> / 0.03766161
>
> The first is the forward conversion, the second is the reciprocal.
> (Use "units -1" if that's annoying.)
>
> > so I've no clue if they might be usable for me. So what is 3Nm equ
> > to?
>
> Most of the advertisements seem to be in oz-in, so to "imperialise",
> I'd:
>
> You have: 3 N m
> You want: ozf in
> Unknown unit 'ozf'
> You want: oz force in
> * 424.8358
> / 0.0023538506
>
> Ah, now, that's substantial, in the size range I tend to look at.
>
> Erik
>
> P.S. As a side issue, I couldn't remember the imperial g, but:
> You have: gravity
> You want: ft/s^2
> * 32.174049
> / 0.03108095
>
> Yes, now I remember using 32, back as a schoolkid, before we went
> metric.
>
Thats all we had when I was in school, in the '40's. The only metrics I 
was exposed to then was in my electronics stuff as I learned it, 
beginning also in the '40's while WW-II was in full swing. :) Theres 
been a whole lot of water under the bridge since then.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] the saga of gene vs pi's continues

[Gene Heskett]

On Saturday 27 May 2017 23:42:17 Todd Zuercher wrote:

> - Original Message -
>
> > And people wonder why I run plumb out of patience. 2 steps fwd, slip
> > and
> > 6 steps back.  Sigh...  I see the light at the end of the tunnel and
> > it
> > runs me over.
> >
> > Cheers, Gene Heskett
> > --
>
> You've the patience of Job.  I'd have pitched that Pi in the rubbish
> bin a long time ago and bought something like this to throw at it.
> https://www.neweggbusiness.com/product/product.aspx?item=9b-13-157-729

Unforch, with that in the box, I'd have to buy another box to put the 
7i90 and 7i42TA's in. And eventually I am out of space behind the lathe.
Not to mention the board might be $65, but memory for it, and a psu that 
might fit in this nice new box, and I'm north of an additional $200 to 
switch back to a wintel system and a fight to get it installed with the 
UEFI bios.  I thought of that when I bought an "up" board with a quad 
core atom on it, no bigger than the pi. But it comes with a UEFI bios 
enabled so you can only install windows 10 on it, and if you turn off 
the UEFI, you've bricked the SOB, and I am not about to throw another 
$350 in a jtag programmer and 50 more for the flashrom clipon just to 
rescue a 100 dollar board. UEFI is something microsoft shoved down our 
throats in another attempt to create a captive customer. Why the 
industry as a whole, didn't sue them out of existence is beyond me. They 
promised it could be turned off if you wanted to install something else, 
but they by damn didn't tell American Megatrends it had to work if it 
was turned off.

Just one of the reasons there are only glass windows in this house.

I'll stop before the air gets even bluer.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] New kind of stepper motor on eBay

[Fox Mulder]

Looks to me just like a stepper motor with integrated motor driver without 
feedback. Maybe the Mechaduino is more like a closed-loop stepper-servo. I have 
ordered some PCBs from DirtyPcb and will assemble them when they arrive. Hope 
they are as good as announced.

https://www.kickstarter.com/projects/tropicallabs/mechaduino-powerful-open-source-industrial-servo-m

https://hackaday.io/project/11224-mechaduino

Ciao,
Rainer

> Am 28.05.2017 um 05:58 schrieb Erik Christiansen :
> 
>> On 27.05.17 16:58, Gene Heskett wrote:
>> I think so too.  But I am so used to thinking in in/lbs, and have never 
>> seen a formula or a chart that converts Nm to in/lbs,
> 
> But on just about any full linux distro under your roof, you have:
> 
> $ units
> You have: 3 N m
> You want: lbf in
>* 26.552237
>/ 0.03766161
> 
> The first is the forward conversion, the second is the reciprocal.
> (Use "units -1" if that's annoying.)
> 
>> so I've no clue if they might be usable for me. So what is 3Nm equ to?
> 
> Most of the advertisements seem to be in oz-in, so to "imperialise", I'd:
> 
> You have: 3 N m
> You want: ozf in
> Unknown unit 'ozf'
> You want: oz force in
>* 424.8358
>/ 0.0023538506
> 
> Ah, now, that's substantial, in the size range I tend to look at.
> 
> Erik
> 
> P.S. As a side issue, I couldn't remember the imperial g, but:
> You have: gravity
> You want: ft/s^2
>* 32.174049
>/ 0.03108095
> 
> Yes, now I remember using 32, back as a schoolkid, before we went
> metric.
> 
> --
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> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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Re: [Emc-users] the saga of gene vs pi's continues

[Erik Christiansen]

On 27.05.17 22:50, Gene Heskett wrote:
> And howinhell do I lock a kernel version,

The one thing for version pinning that I have on record is:

sudo apt-get install linuxcnc=1:2.6.0~pre~joints.axes3~6a281a6

(Substitute your package name and version, naturally.)

I think I'd alias that to a short command I could use without cerebral
effort, and tweak the details for each machine, so it sorts itself out
when you move from one to another.

AFAIR, dpkg and apt-get use the same back end, but apt-get is easier to
deal with - except for one or two simple bits, like local install of a
package already downloaded, which dpkg handles easier.

Erik

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Re: [Emc-users] New kind of stepper motor on eBay

[Erik Christiansen]

On 27.05.17 16:58, Gene Heskett wrote:
> I think so too.  But I am so used to thinking in in/lbs, and have never 
> seen a formula or a chart that converts Nm to in/lbs,

But on just about any full linux distro under your roof, you have:

$ units
You have: 3 N m
You want: lbf in
* 26.552237
/ 0.03766161

The first is the forward conversion, the second is the reciprocal.
(Use "units -1" if that's annoying.)

> so I've no clue if they might be usable for me. So what is 3Nm equ to?

Most of the advertisements seem to be in oz-in, so to "imperialise", I'd:

You have: 3 N m
You want: ozf in
Unknown unit 'ozf'
You want: oz force in
* 424.8358
/ 0.0023538506

Ah, now, that's substantial, in the size range I tend to look at.

Erik

P.S. As a side issue, I couldn't remember the imperial g, but:
You have: gravity
You want: ft/s^2
* 32.174049
/ 0.03108095

Yes, now I remember using 32, back as a schoolkid, before we went
metric.

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Re: [Emc-users] the saga of gene vs pi's continues

[Todd Zuercher]

- Original Message -

> And people wonder why I run plumb out of patience. 2 steps fwd, slip
> and
> 6 steps back.  Sigh...  I see the light at the end of the tunnel and
> it
> runs me over.
> 
> Cheers, Gene Heskett
> --

You've the patience of Job.  I'd have pitched that Pi in the rubbish bin a long 
time ago and bought something like this to throw at it.
https://www.neweggbusiness.com/product/product.aspx?item=9b-13-157-729
 

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[Emc-users] the saga of gene vs pi's continues

[Gene Heskett]

Greetings all;

For lack of anything better to do this after noon I set out to cut and 
assemble the 50 pin jumpers to hook up my purty, all stacked up 
stairstep style, 7i42TA's. But when I plugged it in, it crowbared the 
psu.  And I'm standing there contemplating my sins when I realize the 
7i42TA is bass ackwards, and that I have pin 1 of the 7i90 connected to 
pin 50 on the 7i42TA's.  Duh, so I spent the rest of the day turning the 
7i42TA's around, finding there's no way to stack them facing the other 
way that isn't about an inch and a half too high.  So I did stack the 
firt 2, but set the third on off the end of the 7i90, with the ribbon 
running under the card to get at the far edge, then brought up over the 
far end to arrive at the socket on the 7i42TA.  There went all my plans 
to keep the noise on the right end of the 7i90 and beyond, many inches 
from the pi.  Now I have to bring in lots of noise and connect it right 
on top of the pi.  I can't win. It would have been buckets cleaner if 
the 7i42TA was mirrored so the pin 1's faced each other.

Now, it appears they are being fed not only from the power plugs, but via 
the 50 pin cables, from the 7i90 also, and I see a jumper that might 
have an effect on that in the 7i42TA's, so which is the preferred power 
source giving best performance, Peter? I am thinking I should unplug the 
power plugs from the 7i42TAs as thats a potential ground loop.

I have identified the clock pin on the bottom of the pi, (it's mounted 
upside down to put the 40 pin adjacent to the 7i90 so that the pin ones 
mate w/o needing spaghetti knots in the cable, and I've found a 15 pf 
capacitor I'll stick on it tomorrow for S's.  Progress?  
DamnedifIknow.

But if it works 100% with the cap installed, I'll then verify the 7i90 is 
a good one and not one I've already blown with the noise, its box will 
be assembled and ready to bolt (with electrical insulation to destroy 
ground loops) to the outside face of the motor driver boxes door by 
tomorrow night.  Then its trace everything and hook it back up again.

And howinhell do I lock a kernel version, dpkg, in getting rid of a 
dependency for a doc file, just ripped out all the realtime stuff and 
reinstalled the latest raspian 4.9.26 something non realtime kernel. I 
hope I don't wind up starting all over on this card. dpkg is so slow on 
this pi things that it will be well past midnight local before I can 
reboot to a good kernel again.  Thats 1h:15minutes elapsed time.

And people wonder why I run plumb out of patience. 2 steps fwd, slip and 
6 steps back.  Sigh...  I see the light at the end of the tunnel and it 
runs me over.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] new thread inspired by Christophers question about 3d printer sliceing SW.

[andy pugh]

On 28 May 2017 at 03:06, Sebastian Kuzminsky  wrote:
> Anders Wallin did this back in the halcyon days of 2010:
> https://www.youtube.com/watch?v=VmjhUvA3YLE

Though 7 years on most folk wouldn't class that as a good print :-)


-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1916

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Re: [Emc-users] new thread inspired by Christophers question about 3d printer sliceing SW.

[Sebastian Kuzminsky]

On 05/27/2017 07:54 PM, andy pugh wrote:

On 16 May 2017 at 14:27, Gene Heskett  wrote:

Has anyone put a printhead on a std moving table milling machine, and
used it to do some 3d additive printing?



https://www.youtube.com/watch?v=NEyL6cVWlo4

So, it clearly can work.


Anders Wallin did this back in the halcyon days of 2010: 
https://www.youtube.com/watch?v=VmjhUvA3YLE



--
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Re: [Emc-users] new thread inspired by Christophers question about 3d printer sliceing SW.

[andy pugh]

On 16 May 2017 at 14:27, Gene Heskett  wrote:
> Has anyone put a printhead on a std moving table milling machine, and
> used it to do some 3d additive printing?


https://www.youtube.com/watch?v=NEyL6cVWlo4

So, it clearly can work.

-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1916

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Re: [Emc-users] New kind of stepper motor on eBay

[Andrew]

Hello Chris,

I might be missing something, but I don't think it's a closed loop motor.
They never mention position loop, and I can't see an encoder.

27 трав. 2017 р. 10:56 пп "Chris Albertson" 
пише:

> Hi,
>
> Has anyone here experience with this?
>
> I think these are new.  I've seen them on some web sites and also eBay.   I
> can't find any good engineering information yet, like user manuals or
> speed/torque plots but the idea is great.
>
> They are an integrated closed loop driver/controller and motor.  The
> feedback loop is done inside the motor. They are MUCH better at holding
> torque at high speed than are normal steppers.  More like a servo but at
> much lower cost. The motor accepts DC power (about 36 volts) and step
> and direction.  Here is one example from eBay
>
> Building the driver into the motor is good.  For closed loop control the
> driver must be matched to the motor so you would always buy them in pairs
> anyway.  Placing them in one unit saves the need to run a lot of wire and
> all the noise problems and lowers the over all cost.   The driver cane made
> simpler and cheaper because it does not need to be general purpose, it just
> drive the motor with known inductance and resistance.
>
> http://www.ebay.com/itm/Nema23-57BYG-Stepper-Motor-Integrated-Driver.
>  Integrated-Driver-2-in-1-L112mm-3Nm-24-48VDC-CNC/
> 192011640913?_trksid=p2047675.c15.m1851&_trkparms=aid%
> 3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D40130%26meid%
> 3Dbc8047bd176346b9a8fbf5703256f1ef%26pid%3D15%26rk%3D4%
> 26rkt%3D6%26sd%3D262565354603>
>
> I saw a youtube video demo of one of these that showed it holding
> position.  It was using almost no current and the motor was cool.  But then
> if you apply force to the shaft the current zooms up to counter the applied
> force, like a servo  Basically it IS a servo.  There is an optical
> encoder.  The above web page has a block diagram.
>
> All the good info is in Chinese.  Perhaps someone here is good at technical
> Chinese.  My wife can read only the very basic stuff and Google translation
> is not so good.  I think these are designed and sold into the Chinese
> domestic market hence no US sales office or English technical documents.
>
> This eBay unit is cheaper than a conventional setup.I think this is the
> way things are moving
>
>
> --
>
> Chris Albertson
> Redondo Beach, California
> 
> --
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Re: [Emc-users] New kind of stepper motor on eBay

[Chris Albertson]

Gene,

3Nm is about 425 inch pounds.Roughly 140 in oz to 1Nm

I went to school in the late 70's to early 80's and even then all the
science and engineering classes used metric.  I could not even tell you
what 1g is in Imperial units but it is just under 10 m/sec squared.

In theory freight is the same for any motor of about the same size and
power.

I'm looking for a motor to lift the Z-axis of a Harbor Freight minimill.
Almost every conversion I have seen with the mini mill the Z axis has the
worst performance.   In the design I'm using the z-motor is geared down 2:1
which means it spins faster so lower torque.   This may be the place use
the closed loop 3Nm motor. I'll use a 5-pitch ball screw and 2:1
reduction timing belt drive.  This means the motor sees 10 pitch or .0005
per full step.  and then likely have to use 1/4 steps. The X and Y axis
are pretty light weight, anything would work.

On Sat, May 27, 2017 at 1:58 PM, Gene Heskett  wrote:

> On Saturday 27 May 2017 15:52:54 Chris Albertson wrote:
>
> > Hi,
> >
> > Has anyone here experience with this?
> >
> > I think these are new.  I've seen them on some web sites and also
> > eBay.   I can't find any good engineering information yet, like user
> > manuals or speed/torque plots but the idea is great.
>
> I think so too.  But I am so used to thinking in in/lbs, and have never
> seen a formula or a chart that converts Nm to in/lbs, so I've no clue if
> they might be usable for me.  So what is 3Nm equ to?
>
> I haven't a clue if it would fit for the X drive on the Sheldon, and not
> hit the bed at 112mm long.  It would awfull close, little or no room for
> paint.
> >
> > They are an integrated closed loop driver/controller and motor.  The
> > feedback loop is done inside the motor. They are MUCH better at
> > holding torque at high speed than are normal steppers.  More like a
> > servo but at much lower cost. The motor accepts DC power (about 36
> > volts) and step and direction.  Here is one example from eBay
> >
> > Building the driver into the motor is good.  For closed loop control
> > the driver must be matched to the motor so you would always buy them
> > in pairs anyway.  Placing them in one unit saves the need to run a lot
> > of wire and all the noise problems and lowers the over all cost.   The
> > driver cane made simpler and cheaper because it does not need to be
> > general purpose, it just drive the motor with known inductance and
> > resistance.
> >
> > http://www.ebay.com/itm/Nema23-57BYG-Stepper-Motor-Integrated-Driver..
> >...
> >  >2-in-1-L112mm-3Nm-24-48VDC-CNC/192011640913?_trksid=p2047675.c15.m1
> >851&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D40130%26me
> >id%3Dbc8047bd176346b9a8fbf5703256f1ef%26pid%3D15%26rk%3D4%26rkt%3D6
> >%26sd%3D262565354603>
> >
> > I saw a youtube video demo of one of these that showed it holding
> > position.  It was using almost no current and the motor was cool.  But
> > then if you apply force to the shaft the current zooms up to counter
> > the applied force, like a servo  Basically it IS a servo.  There is an
> > optical encoder.  The above web page has a block diagram.
> >
> > All the good info is in Chinese.  Perhaps someone here is good at
> > technical Chinese.  My wife can read only the very basic stuff and
> > Google translation is not so good.  I think these are designed and
> > sold into the Chinese domestic market hence no US sales office or
> > English technical documents.
> >
> > This eBay unit is cheaper than a conventional setup.I think this
> > is the way things are moving
>
> I'm sure of it. That posted price is about $65 less than when I checked
> last.  So the switchover will be considerably speeded up unless the
> freight eats the difference.  And it does eat much of it at $38 freight
> from HongKong. That brings the per axis cost up to $126 for the 3Nm
> unit.
>
> Cheers, Gene Heskett
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> Genes Web page 
>
> 
> --
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> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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-- 

Chris Albertson
Redondo Beach, California
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Re: [Emc-users] New kind of stepper motor on eBay

[Ken Strauss]

> -Original Message-
> From: andy pugh [mailto:bodge...@gmail.com]
> Sent: Saturday, May 27, 2017 6:06 PM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] New kind of stepper motor on eBay
>
> On 27 May 2017 at 21:58, Gene Heskett  wrote:
> > I think so too.  But I am so used to thinking in in/lbs, and have
> > never seen a formula or a chart that converts Nm to in/lbs, so I've no
> > clue if they might be usable for me.  So what is 3Nm equ to?
>
> Is that lbs mass or lbs force?
>
> 1Nm is 8.85 lb-in. Or about 3/4 of a lb-ft.
>
> --

They sound similar to the stuff from Clearpath:
https://www.teknic.com/products/clearpath-brushless-dc-servo-motors/




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Re: [Emc-users] New kind of stepper motor on eBay

[andy pugh]

On 27 May 2017 at 21:58, Gene Heskett  wrote:
> I think so too.  But I am so used to thinking in in/lbs, and have never
> seen a formula or a chart that converts Nm to in/lbs, so I've no clue if
> they might be usable for me.  So what is 3Nm equ to?

Is that lbs mass or lbs force?

1Nm is 8.85 lb-in. Or about 3/4 of a lb-ft.

-- 
atp
"A motorcycle is a bicycle with a pandemonium attachment and is
designed for the especial use of mechanical geniuses, daredevils and
lunatics."
— George Fitch, Atlanta Constitution Newspaper, 1916

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Re: [Emc-users] New kind of stepper motor on eBay

[Gene Heskett]

On Saturday 27 May 2017 15:52:54 Chris Albertson wrote:

> Hi,
>
> Has anyone here experience with this?
>
> I think these are new.  I've seen them on some web sites and also
> eBay.   I can't find any good engineering information yet, like user
> manuals or speed/torque plots but the idea is great.

I think so too.  But I am so used to thinking in in/lbs, and have never 
seen a formula or a chart that converts Nm to in/lbs, so I've no clue if 
they might be usable for me.  So what is 3Nm equ to?

I haven't a clue if it would fit for the X drive on the Sheldon, and not 
hit the bed at 112mm long.  It would awfull close, little or no room for 
paint.
>
> They are an integrated closed loop driver/controller and motor.  The
> feedback loop is done inside the motor. They are MUCH better at
> holding torque at high speed than are normal steppers.  More like a
> servo but at much lower cost. The motor accepts DC power (about 36
> volts) and step and direction.  Here is one example from eBay
>
> Building the driver into the motor is good.  For closed loop control
> the driver must be matched to the motor so you would always buy them
> in pairs anyway.  Placing them in one unit saves the need to run a lot
> of wire and all the noise problems and lowers the over all cost.   The
> driver cane made simpler and cheaper because it does not need to be
> general purpose, it just drive the motor with known inductance and
> resistance.
>
> http://www.ebay.com/itm/Nema23-57BYG-Stepper-Motor-Integrated-Driver..
>...
> 2-in-1-L112mm-3Nm-24-48VDC-CNC/192011640913?_trksid=p2047675.c15.m1
>851&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D40130%26me
>id%3Dbc8047bd176346b9a8fbf5703256f1ef%26pid%3D15%26rk%3D4%26rkt%3D6
>%26sd%3D262565354603>
>
> I saw a youtube video demo of one of these that showed it holding
> position.  It was using almost no current and the motor was cool.  But
> then if you apply force to the shaft the current zooms up to counter
> the applied force, like a servo  Basically it IS a servo.  There is an
> optical encoder.  The above web page has a block diagram.
>
> All the good info is in Chinese.  Perhaps someone here is good at
> technical Chinese.  My wife can read only the very basic stuff and
> Google translation is not so good.  I think these are designed and
> sold into the Chinese domestic market hence no US sales office or
> English technical documents.
>
> This eBay unit is cheaper than a conventional setup.I think this
> is the way things are moving

I'm sure of it. That posted price is about $65 less than when I checked 
last.  So the switchover will be considerably speeded up unless the 
freight eats the difference.  And it does eat much of it at $38 freight 
from HongKong. That brings the per axis cost up to $126 for the 3Nm 
unit.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] New kind of stepper motor on eBay

[Marcus Bowman]

I read  about these a little while ago. They are not Chinese; they are made in 
the USA.
I seem to remember they were a Kickstarter campaign, and I read a bit about 
them on Hackaday.
Seemed like a good idea, but they are expensive.
Maybe the Chinese copies are cheaper, of course.
The maths they are based on is interesting, and somewhat complex, but clever.

Marcus 

On 27 May 2017, at 20:52, Chris Albertson wrote:

> Hi,
> 
> Has anyone here experience with this?
> 
> I think these are new.  I've seen them on some web sites and also eBay.   I
> can't find any good engineering information yet, like user manuals or
> speed/torque plots but the idea is great.
> 
> They are an integrated closed loop driver/controller and motor.  The
> feedback loop is done inside the motor. They are MUCH better at holding
> torque at high speed than are normal steppers.  More like a servo but at
> much lower cost. The motor accepts DC power (about 36 volts) and step
> and direction.  Here is one example from eBay
> 
> Building the driver into the motor is good.  For closed loop control the
> driver must be matched to the motor so you would always buy them in pairs
> anyway.  Placing them in one unit saves the need to run a lot of wire and
> all the noise problems and lowers the over all cost.   The driver cane made
> simpler and cheaper because it does not need to be general purpose, it just
> drive the motor with known inductance and resistance.
> 
> http://www.ebay.com/itm/Nema23-57BYG-Stepper-Motor-Integrated-Driver.
> 
> 
> I saw a youtube video demo of one of these that showed it holding
> position.  It was using almost no current and the motor was cool.  But then
> if you apply force to the shaft the current zooms up to counter the applied
> force, like a servo  Basically it IS a servo.  There is an optical
> encoder.  The above web page has a block diagram.
> 
> All the good info is in Chinese.  Perhaps someone here is good at technical
> Chinese.  My wife can read only the very basic stuff and Google translation
> is not so good.  I think these are designed and sold into the Chinese
> domestic market hence no US sales office or English technical documents.
> 
> This eBay unit is cheaper than a conventional setup.I think this is the
> way things are moving
> 
> 
> -- 
> 
> Chris Albertson
> Redondo Beach, California
> --
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> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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Re: [Emc-users] switching to a slower spi driver to see if it works,

[Gene Heskett]

On Saturday 27 May 2017 15:14:55 Charles Steinkuehler wrote:

> On 5/27/2017 12:21 PM, Gene Heskett wrote:
> > On Saturday 27 May 2017 11:26:18 Peter C. Wallace wrote:
> >> You might try lowering the series termination resistor value since
> >> this looks like a possible SI issue (and the clock signal will be
> >> very sensitive to SI issues).
> >
> > SI? Acronym for what?
>
> Signal integrity.
>
> Source, cable, and load impedance all need to match pretty well, but
> you knew that already.  :)
>
> If you're running any distance, I'd recommend a buffer on the SPI
> lines.  The SoC parts are designed to drive short PCB traces and
> typically only have a few mA of drive, not really enough to properly
> drive a cable and it's capacitance.  For series termination to work
> well, the driver needs enough current output to drive the full signal
> across the series termination resistor.  Otherwise, you wind up
> needing two full cable round-trip times to get a reliable signal at
> the far end, and you leave the load sitting halfway through the
> transition for a cable round-trip time.
>
> I'd wager if you just stick a reasonably fast driver (AHCT, LVC, or
> just about any 3.3V logic family) on the clock like at the RPi end to
> drive the cable (with a suitable[1] series resistor, probably 25-33
> ohm), your problems will go away.
>
> [1] The driver output impedance plus the series termination resistor
> should equal the characteristic impedance of the cable.  Most cables
> (ribbon with alternating ground, twisted pair Ethernet) are going to
> be around 100-120 ohms.  The driver needs to be able to drive a full
> step (3.3V or 5V, depending on your logic family) into the effective
> impedance of the cable impedance plus the driver & series terminator
> (so 200-240 ohms).  The I/O drivers on most SoC parts just aren't big
> enough to be able to do that effectively, so it takes two round-trip
> flight times to bring the load end to the final voltage, which also
> typically leaves the load end sitting in the transition region for one
> round-trip flight time.  A recipe for problems when you're talking
> about a clock line.

This all sounds like a redesign of the adapter board, with good rail 
bypassing at those frequencies. If thats the case, can I request that 
the 26 pin socket be put on the same side of the board as the 40 pinner? 
That would make it hang over the edge of the pi, and that would allow a 
3/4" cable to be made.  At what point in shortening the cable can the 
terms be thrown away? My mental calcs tell me the cable ringing at 1.25" 
would be at quite a few gigahertz, and any ringing would be faster than 
the semi's on either end of it can either generate or respond to, so the 
losses in the term resistors can be eliminated by shorting them out. In 
the interests of shortening this cable, the pi for this second build has 
been turned upside down with the 40 pin gpio placed immediately inline 
with the 7i90 26 pin socket with perhaps 3/4" inch between them.
I could post a pix if anybody is interested.

Cheers, Gene Heskett
-- 
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 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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[Emc-users] New kind of stepper motor on eBay

[Chris Albertson]

Hi,

Has anyone here experience with this?

I think these are new.  I've seen them on some web sites and also eBay.   I
can't find any good engineering information yet, like user manuals or
speed/torque plots but the idea is great.

They are an integrated closed loop driver/controller and motor.  The
feedback loop is done inside the motor. They are MUCH better at holding
torque at high speed than are normal steppers.  More like a servo but at
much lower cost. The motor accepts DC power (about 36 volts) and step
and direction.  Here is one example from eBay

Building the driver into the motor is good.  For closed loop control the
driver must be matched to the motor so you would always buy them in pairs
anyway.  Placing them in one unit saves the need to run a lot of wire and
all the noise problems and lowers the over all cost.   The driver cane made
simpler and cheaper because it does not need to be general purpose, it just
drive the motor with known inductance and resistance.

http://www.ebay.com/itm/Nema23-57BYG-Stepper-Motor-Integrated-Driver.


I saw a youtube video demo of one of these that showed it holding
position.  It was using almost no current and the motor was cool.  But then
if you apply force to the shaft the current zooms up to counter the applied
force, like a servo  Basically it IS a servo.  There is an optical
encoder.  The above web page has a block diagram.

All the good info is in Chinese.  Perhaps someone here is good at technical
Chinese.  My wife can read only the very basic stuff and Google translation
is not so good.  I think these are designed and sold into the Chinese
domestic market hence no US sales office or English technical documents.

This eBay unit is cheaper than a conventional setup.I think this is the
way things are moving


-- 

Chris Albertson
Redondo Beach, California
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Re: [Emc-users] switching to a slower spi driver to see if it works,

[Gene Heskett]

On Saturday 27 May 2017 13:53:51 Bertho Stultiens wrote:

> On 05/27/2017 02:41 PM, Gene Heskett wrote:
> [snip]
>
> > If I can rebuild just this module on the pi itself, that is TBD.
>
> Gene, can you specify which base-distro you run on the Pi and which
> kernel? I'd like to reproduce your problem here on the bench and see
> if I can hack a fix.
>
pi@pionsheldon:~ $ uname -a
Linux pionsheldon 4.4.9-rt17-v7+ #1 SMP PREEMPT RT Wed May 11 22:46:14 
CEST 2016 armv7l GNU/Linux

pi@pionsheldon:~ $ cat /etc/issue
Raspbian GNU/Linux 8 \n \l

> Also, what options do you have on the linuxcnc configure. Just to make
> similar systems.

the configure-$version number in /boot does not match the running kernel 
as this was an emlid based install, and the rt kernel has overwritten 
their 4.4.6 version kernel and kernel7 files. So although I had to 
install more utils, both pi's are pretty close to matching the above, 
with uname -a and /etc/issue being a 100% match.

> I do not have the hm2 hardware, but that should not prevent me from
> seeing the problem on the SPI bus.

I think you'll have to have the hm2 hardware, although I'll be glad to be 
the lab rat if you want to PM me the newly built modules.

I've been out shopping & pill collecting, and I've got to reload the 
dishwasher in order to find the sink, so I'll be busy for the next half 
hour at least.
>
> >>> What should I do next?
> >>
> >> Try and try again?
> >> ;-)
> >
> > Thats not the smiley I'd use.
>
> Well, I'm still smiling, hope you are too.

I am at the thought that you might build us a working driver. ;-)

Thanks Bertho Stultiens.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] switching to a slower spi driver to see if it works,

[Charles Steinkuehler]

On 5/27/2017 12:21 PM, Gene Heskett wrote:
> On Saturday 27 May 2017 11:26:18 Peter C. Wallace wrote:
> 
>> You might try lowering the series termination resistor value since
>> this looks like a possible SI issue (and the clock signal will be very
>> sensitive to SI issues).
> 
> SI? Acronym for what?

Signal integrity.

Source, cable, and load impedance all need to match pretty well, but
you knew that already.  :)

If you're running any distance, I'd recommend a buffer on the SPI
lines.  The SoC parts are designed to drive short PCB traces and
typically only have a few mA of drive, not really enough to properly
drive a cable and it's capacitance.  For series termination to work
well, the driver needs enough current output to drive the full signal
across the series termination resistor.  Otherwise, you wind up
needing two full cable round-trip times to get a reliable signal at
the far end, and you leave the load sitting halfway through the
transition for a cable round-trip time.

I'd wager if you just stick a reasonably fast driver (AHCT, LVC, or
just about any 3.3V logic family) on the clock like at the RPi end to
drive the cable (with a suitable[1] series resistor, probably 25-33
ohm), your problems will go away.

[1] The driver output impedance plus the series termination resistor
should equal the characteristic impedance of the cable.  Most cables
(ribbon with alternating ground, twisted pair Ethernet) are going to
be around 100-120 ohms.  The driver needs to be able to drive a full
step (3.3V or 5V, depending on your logic family) into the effective
impedance of the cable impedance plus the driver & series terminator
(so 200-240 ohms).  The I/O drivers on most SoC parts just aren't big
enough to be able to do that effectively, so it takes two round-trip
flight times to bring the load end to the final voltage, which also
typically leaves the load end sitting in the transition region for one
round-trip flight time.  A recipe for problems when you're talking
about a clock line.

-- 
Charles Steinkuehler
char...@steinkuehler.net

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Re: [Emc-users] CC-Link emc2

[theman whosoldtheworld]

ok ... T-bird is fantastic ... I use it on my work place .. more
custumisation is possible and good mail code analisys interface ... any how
if you would separate in definitive manner work mail and other or install
(or create) multiple interfaces or use web mail.

bkt

2017-05-27 13:56 GMT+02:00 Mark :

> On 05/26/2017 11:22 PM, Erik Christiansen wrote:
>
>>
>> Dunno much about GUI offerings, but for a local no-spyware alternative,
>> mutt displays thread trees very nicely, and collapses/expands them at
>> your will. When it comes time to archive (the messages you've kept from)
>> a thread to another mailbox, the whole thread can be tagged and treated
>> as a unit for the archive/delete/... action. Wouldn't swap it for a ton
>> of tea.
>>
>> My local LinuxCNC archive is sorted into a bunch of topics, for quick
>> reference:
>>
>> $ ls -1 mail/cnc_linux_* | wc -l
>> 447
>>
>> But maybe Gmail can do that too ... and reaching for the mouse all the
>> time provides more exercise, which is good.
>>
>> Erik
>> (Who's carted some bricks, and quartered a small Blackwood log with the
>> chainsaw today, so will pass on the extra exercise.)
>>
>
> Forgot to mention on the previous posts that T-bird does threading quite
> well and also has a well developed filter system to plunk inbound mails to
> a specific mailbox.  This one lands in a mailbox called EMC2 (I left it at
> that name for nostalgia reasons ;-) ), along with plenty of keyboard
> shortcuts so the mouse isn't quite the necessary evil required in Winders
> land here on this Ubuntu machine.
>
> Mark
>
>
> 
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Re: [Emc-users] switching to a slower spi driver to see if it works,

[Bertho Stultiens]

On 05/27/2017 02:41 PM, Gene Heskett wrote:
[snip]
> If I can rebuild just this module on the pi itself, that is TBD.

Gene, can you specify which base-distro you run on the Pi and which
kernel? I'd like to reproduce your problem here on the bench and see if
I can hack a fix.

Also, what options do you have on the linuxcnc configure. Just to make
similar systems.

I do not have the hm2 hardware, but that should not prevent me from
seeing the problem on the SPI bus.


>>> What should I do next?
>> Try and try again?
>> ;-)
> Thats not the smiley I'd use.

Well, I'm still smiling, hope you are too.


-- 
Greetings Bertho

(disclaimers are disclaimed)

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Re: [Emc-users] switching to a slower spi driver to see if it works,

[Gene Heskett]

On Saturday 27 May 2017 11:26:18 Peter C. Wallace wrote:

> On Sat, 27 May 2017, Gene Heskett wrote:
> > Date: Sat, 27 May 2017 08:41:26 -0400
> > From: Gene Heskett 
> > Reply-To: "Enhanced Machine Controller (EMC)"
> > 
> > To: emc-users@lists.sourceforge.net
> > Subject: Re: [Emc-users] switching to a slower spi driver to see if
> > it works,
[...]
> You might try lowering the series termination resistor value since
> this looks like a possible SI issue (and the clock signal will be very
> sensitive to SI issues).

SI? Acronym for what?

> Also standard 10M capacitive divider probles are pretty useless for
> high speed signal waverform checking, they have way too much
> capacitance and typically poor step response.

I've no clue how accurately shaped the 1 KHz test signal is, but expanded 
to see at 2ns per division, it actually looks pretty good.

However, the clock signal as I see it on this gigahertz sampler, is not 
too terrible removed from a sine-squared wave, so I'm not convinced I am 
looking at the truth.  At the pi, the swing is 3.35 volts, beyond the 
term r its under 2.9 volts for swing, like the 7i90 is pulling it up 
pretty strongly.
>
> I would suggest tacking a 4.99K resistor on the end of a bit of 50 Ohm
> COAX to make a 100-1 passive divider probe with ~1 GHz band with and
> less than 1 PF input capacitance (assuming you have a 50 Ohm Scope
> input option)

This Chinese scope doesn't have a 50 ohm input. Std 1 meg. And probably 
about 50 pf. But its a thought, I'll see what I can cobble up right at 
the input bnc connector. And all the coax I can lay my hands on is 75 
(73 actually) ohm. Video stuff. In the meantime, I found some 6mm dia. 
30 pf max trimmers, 20 for about 7 dollars, s/b here around the 5th.  On 
fleabay of course.  That might get me going as they can be pasted on the 
back face of the 40 pin pattern.

Getting at the smd pad to parallel another resistor will be fun, the 
header sockets are sitting on them. And even with hot air, I'm not sure 
I could R the header sockets without damaging the board in addition to 
trashing the headers. At a 1.25" cable length, I'd think I ought to be 
able to just bridge the pads.  Theres not enough drive to damage 
anything.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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Re: [Emc-users] switching to a slower spi driver to see if it works,

[Peter C. Wallace]

On Sat, 27 May 2017, Gene Heskett wrote:


Date: Sat, 27 May 2017 08:41:26 -0400
From: Gene Heskett 
Reply-To: "Enhanced Machine Controller (EMC)"

To: emc-users@lists.sourceforge.net
Subject: Re: [Emc-users] switching to a slower spi driver to see if it works, 


On Saturday 27 May 2017 04:49:51 Bertho Stultiens wrote:


On 05/27/2017 05:46 AM, Gene Heskett wrote:
[snip]


This is the exact same response from the 7i90 at the initial 50 MHz
clocking:

pi@pionsheldon:~ $ linuxcnc -l
LINUXCNC - 2.8.0-pre1-2771-gdc2ff49
Machine configuration directory
is '/home/pi/linuxcnc/configs/sheldon-lathe'
Machine configuration file is '7i90-axis.ini'
Starting LinuxCNC...
Found file(REL): ./hm2-7i90-stepper.hal
Note: Using POSIX realtime
hm2: loading Mesa HostMot2 driver version 0.15
Unknown board: HOST  <-- same exact but wrong response


[snip]

This is printed at line 314 in
src/hal/drivers/mesa-hostmot2/hm2_rpspi.c in the probe_board()
function.

[snip]


With the demise of the armhf build machine, where do I find the srcs
for this driver?


Isn't this at:
https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/drivers/mesa-
hostmot2/hm2_rpspi.c


It makes sense to me to fix the driver rather than trying
to hack up a capacitor...[snip]


Yes, indeed, fixing the driver would be the correct way.

I just had a look at the code (from above link) and it does not make
much sense that the first access to the card is at 50 MHz and
subsequently 32 MHz.

The SPI interface is configured once in setup_gpio() and then the
hardware config is used as is from then on. Therefore, once the
hardware registers are set, it should work the same way every time.

The behavior reminds me of one possible problem, caching. If that is
the problem, then loading the module a second time should not give you
the 50 MHz initial board-probe, but the 32 MHz as set before.



If loading the module twice give you the same result, then it may be
possible that the hardware will only change setup once activated
(maybe through CS cycling). Therefore, the board-probe may be (partly)
at high speed, then the hardware discovers it has a new setup and
subsequently uses the correct hardware register setup.

You can verify the hypothesis by looking at the scope. There are
actually two commands sent: read cookie and read board ident (you
should see two assertions of CS in that process). If the first 16
bytes are read at 50 MHz and the next 8 bytes at 32 MHz, then the
hardware is switching speed after the first transfer.


I would tend to think that the theory was if it works at 50 MHz, then it
ought to be rock solid at 32 MHz.  The switch to 32 MHz then assures it
works well within its limits.

Its been quite a while since I kicked any tires in C, but I've copied the
file, and see if I can see a way to lag the clock by a few nanoseconds
since it seems to work well with the 10x scope probe attached.  The
scope doesn't have to be on, just attached.


If so, then there may be a simple work-around for the problem. Alter
the code to do a dummy read in probe_board() (calling
check_cookie()/read_ident(), see lines 292 and 296) and discarding the
result in the first go. Then the second iteration is used as the
actual probe, where the hardware should be running at the correct
speed.

The thing is, one peculiarity speaks against the hypothesis. You do
not see an error message "Invalid Cookie", which is emitted when
reading the cookie fails. This is the first transfer, which, under my
hypothesis, should fail at the 50 MHz speed.


I have seen the bad cookie message too but its much rarer. Easy to get
though, just move the probe to the 7i90 side of the termination
resistor. That loading shows a reduced swing of the clock, just enough
I'd guess the 7i90 never sees a logic 0. In that event the cookie is
printed as:
   
It never gets below .95 volts, nor above 2.75 volts.  These are the
probes that came with the scope.

I am tempted to replace them with the 200MHz rated probes from mpja.com.
Hmmm, I may already have them, on the Hitachi v1065.



You might try lowering the series termination resistor value since this looks 
like a possible SI issue (and the clock signal will be very sensitive to SI 
issues).


Also standard 10M capacitive divider probles are pretty useless for high speed 
signal waverform checking, they have way too much capacitance and typically 
poor step response.


I would suggest tacking a 4.99K resistor on the end of a bit of 50 Ohm COAX
to make a 100-1 passive divider probe with ~1 GHz band with and less than 1 
PF input capacitance (assuming you have a 50 Ohm Scope input option)







Anyhow, it might be worth a try.


If I can rebuild just this module on the pi itself, that is TBD.

build-essential is on it. But it reminds me that:
[snip]
build-essential is already the newest version.
You might want to run 'apt-get -f install' to correct these:
The 

Re: [Emc-users] switching to a slower spi driver to see if it works,

[Gene Heskett]

On Saturday 27 May 2017 04:49:51 Bertho Stultiens wrote:

> On 05/27/2017 05:46 AM, Gene Heskett wrote:
> [snip]
>
> > This is the exact same response from the 7i90 at the initial 50 MHz
> > clocking:
> >
> > pi@pionsheldon:~ $ linuxcnc -l
> > LINUXCNC - 2.8.0-pre1-2771-gdc2ff49
> > Machine configuration directory
> > is '/home/pi/linuxcnc/configs/sheldon-lathe'
> > Machine configuration file is '7i90-axis.ini'
> > Starting LinuxCNC...
> > Found file(REL): ./hm2-7i90-stepper.hal
> > Note: Using POSIX realtime
> > hm2: loading Mesa HostMot2 driver version 0.15
> > Unknown board: HOST  <-- same exact but wrong response
>
> [snip]
>
> This is printed at line 314 in
> src/hal/drivers/mesa-hostmot2/hm2_rpspi.c in the probe_board()
> function.
>
> [snip]
>
> > With the demise of the armhf build machine, where do I find the srcs
> > for this driver?
>
> Isn't this at:
> https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/drivers/mesa-
>hostmot2/hm2_rpspi.c
>
> > It makes sense to me to fix the driver rather than trying
> > to hack up a capacitor...[snip]
>
> Yes, indeed, fixing the driver would be the correct way.
>
> I just had a look at the code (from above link) and it does not make
> much sense that the first access to the card is at 50 MHz and
> subsequently 32 MHz.
>
> The SPI interface is configured once in setup_gpio() and then the
> hardware config is used as is from then on. Therefore, once the
> hardware registers are set, it should work the same way every time.
>
> The behavior reminds me of one possible problem, caching. If that is
> the problem, then loading the module a second time should not give you
> the 50 MHz initial board-probe, but the 32 MHz as set before.

> If loading the module twice give you the same result, then it may be
> possible that the hardware will only change setup once activated
> (maybe through CS cycling). Therefore, the board-probe may be (partly)
> at high speed, then the hardware discovers it has a new setup and
> subsequently uses the correct hardware register setup.
>
> You can verify the hypothesis by looking at the scope. There are
> actually two commands sent: read cookie and read board ident (you
> should see two assertions of CS in that process). If the first 16
> bytes are read at 50 MHz and the next 8 bytes at 32 MHz, then the
> hardware is switching speed after the first transfer.
>
I would tend to think that the theory was if it works at 50 MHz, then it 
ought to be rock solid at 32 MHz.  The switch to 32 MHz then assures it 
works well within its limits.

Its been quite a while since I kicked any tires in C, but I've copied the 
file, and see if I can see a way to lag the clock by a few nanoseconds 
since it seems to work well with the 10x scope probe attached.  The 
scope doesn't have to be on, just attached.

> If so, then there may be a simple work-around for the problem. Alter
> the code to do a dummy read in probe_board() (calling
> check_cookie()/read_ident(), see lines 292 and 296) and discarding the
> result in the first go. Then the second iteration is used as the
> actual probe, where the hardware should be running at the correct
> speed.
>
> The thing is, one peculiarity speaks against the hypothesis. You do
> not see an error message "Invalid Cookie", which is emitted when
> reading the cookie fails. This is the first transfer, which, under my
> hypothesis, should fail at the 50 MHz speed.
>
I have seen the bad cookie message too but its much rarer. Easy to get 
though, just move the probe to the 7i90 side of the termination 
resistor. That loading shows a reduced swing of the clock, just enough 
I'd guess the 7i90 never sees a logic 0. In that event the cookie is 
printed as:
   
It never gets below .95 volts, nor above 2.75 volts.  These are the 
probes that came with the scope.

I am tempted to replace them with the 200MHz rated probes from mpja.com.
Hmmm, I may already have them, on the Hitachi v1065.

> Anyhow, it might be worth a try.

If I can rebuild just this module on the pi itself, that is TBD.

build-essential is on it. But it reminds me that:
[snip]
build-essential is already the newest version.
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 libraspberrypi-doc : Depends: libraspberrypi0 (= 1.20170427-1) but it is 
not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or 
specify a solution).
pi@pionsheldon:~ $ sudo apt-get -f install
Reading package lists... Done
Building dependency tree   
Reading state information... Done
Correcting dependencies... Done
The following extra packages will be installed:
  libraspberrypi0 raspberrypi-bootloader
The following NEW packages will be installed:
  libraspberrypi0 raspberrypi-bootloader
0 upgraded, 2 newly installed, 0 to remove and 0 not upgraded.
22 not fully installed or removed.
Need to get 0 B/4,147 kB of archives.
After this operation, 16.3 

Re: [Emc-users] CC-Link emc2

[Mark]

On 05/26/2017 11:22 PM, Erik Christiansen wrote:


Dunno much about GUI offerings, but for a local no-spyware alternative,
mutt displays thread trees very nicely, and collapses/expands them at
your will. When it comes time to archive (the messages you've kept from)
a thread to another mailbox, the whole thread can be tagged and treated
as a unit for the archive/delete/... action. Wouldn't swap it for a ton
of tea.

My local LinuxCNC archive is sorted into a bunch of topics, for quick
reference:

$ ls -1 mail/cnc_linux_* | wc -l
447

But maybe Gmail can do that too ... and reaching for the mouse all the
time provides more exercise, which is good.

Erik
(Who's carted some bricks, and quartered a small Blackwood log with the
chainsaw today, so will pass on the extra exercise.)


Forgot to mention on the previous posts that T-bird does threading quite 
well and also has a well developed filter system to plunk inbound mails 
to a specific mailbox.  This one lands in a mailbox called EMC2 (I left 
it at that name for nostalgia reasons ;-) ), along with plenty of 
keyboard shortcuts so the mouse isn't quite the necessary evil required 
in Winders land here on this Ubuntu machine.


Mark

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Re: [Emc-users] CC-Link emc2

[Mark]

On 05/26/2017 06:15 PM, andy pugh wrote:


It's too late, I have been using Gmail exclusively for many years. (I
like how it threads mailing lists).


Ditto, though I refuse to use the web interface.  I download my emails 
to Thunderbird on my local laptop, an HP running Ubuntu 16.04 LTS.  Have 
experienced no problems, and no ads.


Mark

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Re: [Emc-users] CC-Link emc2

[theman whosoldtheworld]

gmail can store the mailing list as forum manner ... so is more simple to
read all post ... no local archive ... Nothing local from the web ...
security issue

bkt

2017-05-27 5:22 GMT+02:00 Erik Christiansen :

> On 26.05.17 23:15, andy pugh wrote:
> > On 26 May 2017 at 23:01, theman whosoldtheworld 
> wrote:
> > > you are right  so for emc-user-list protection  i find other
> > > solution
> >
> > It's too late, I have been using Gmail exclusively for many years. (I
> > like how it threads mailing lists).
>
> Dunno much about GUI offerings, but for a local no-spyware alternative,
> mutt displays thread trees very nicely, and collapses/expands them at
> your will. When it comes time to archive (the messages you've kept from)
> a thread to another mailbox, the whole thread can be tagged and treated
> as a unit for the archive/delete/... action. Wouldn't swap it for a ton
> of tea.
>
> My local LinuxCNC archive is sorted into a bunch of topics, for quick
> reference:
>
> $ ls -1 mail/cnc_linux_* | wc -l
> 447
>
> But maybe Gmail can do that too ... and reaching for the mouse all the
> time provides more exercise, which is good.
>
> Erik
> (Who's carted some bricks, and quartered a small Blackwood log with the
> chainsaw today, so will pass on the extra exercise.)
>
> 
> --
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> engaging tech sites, Slashdot.org! http://sdm.link/slashdot
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Re: [Emc-users] CC-Link emc2

[theman whosoldtheworld]

So I continue my quite good experiences with gmail (it's seems well
structured for mailing list, forum and these tipe of things ...)
I normally do not worry about privacy because I fix the problem to the
origin ... and take it for granted that others do the same 
I believe I will have to make my apologies to Gene for my decision  ... I
more simple for me to use Mozzila anti traking and other features that help
to nùknow where your kookis are send.

bkt

2017-05-27 0:15 GMT+02:00 andy pugh :

> On 26 May 2017 at 23:01, theman whosoldtheworld 
> wrote:
> > you are right  so for emc-user-list protection  i find other
> > solution
>
> It's too late, I have been using Gmail exclusively for many years. (I
> like how it threads mailing lists).
>
> --
> atp
> "A motorcycle is a bicycle with a pandemonium attachment and is
> designed for the especial use of mechanical geniuses, daredevils and
> lunatics."
> — George Fitch, Atlanta Constitution Newspaper, 1916
>
> 
> --
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Re: [Emc-users] switching to a slower spi driver to see if it works,

[Bertho Stultiens]

On 05/27/2017 05:46 AM, Gene Heskett wrote:
[snip]
> This is the exact same response from the 7i90 at the initial 50 MHz 
> clocking:
> 
> pi@pionsheldon:~ $ linuxcnc -l
> LINUXCNC - 2.8.0-pre1-2771-gdc2ff49
> Machine configuration directory 
> is '/home/pi/linuxcnc/configs/sheldon-lathe'
> Machine configuration file is '7i90-axis.ini'
> Starting LinuxCNC...
> Found file(REL): ./hm2-7i90-stepper.hal
> Note: Using POSIX realtime
> hm2: loading Mesa HostMot2 driver version 0.15
> Unknown board: HOST  <-- same exact but wrong response
[snip]

This is printed at line 314 in src/hal/drivers/mesa-hostmot2/hm2_rpspi.c
in the probe_board() function.

[snip]
> With the demise of the armhf build machine, where do I find the srcs for 
> this driver?

Isn't this at:
https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/drivers/mesa-hostmot2/hm2_rpspi.c


> It makes sense to me to fix the driver rather than trying 
> to hack up a capacitor...[snip]

Yes, indeed, fixing the driver would be the correct way.

I just had a look at the code (from above link) and it does not make
much sense that the first access to the card is at 50 MHz and
subsequently 32 MHz.

The SPI interface is configured once in setup_gpio() and then the
hardware config is used as is from then on. Therefore, once the hardware
registers are set, it should work the same way every time.

The behavior reminds me of one possible problem, caching. If that is the
problem, then loading the module a second time should not give you the
50 MHz initial board-probe, but the 32 MHz as set before.

If loading the module twice give you the same result, then it may be
possible that the hardware will only change setup once activated (maybe
through CS cycling). Therefore, the board-probe may be (partly) at high
speed, then the hardware discovers it has a new setup and subsequently
uses the correct hardware register setup.

You can verify the hypothesis by looking at the scope. There are
actually two commands sent: read cookie and read board ident (you should
see two assertions of CS in that process). If the first 16 bytes are
read at 50 MHz and the next 8 bytes at 32 MHz, then the hardware is
switching speed after the first transfer.

If so, then there may be a simple work-around for the problem. Alter the
code to do a dummy read in probe_board() (calling
check_cookie()/read_ident(), see lines 292 and 296) and discarding the
result in the first go. Then the second iteration is used as the actual
probe, where the hardware should be running at the correct speed.

The thing is, one peculiarity speaks against the hypothesis. You do not
see an error message "Invalid Cookie", which is emitted when reading the
cookie fails. This is the first transfer, which, under my hypothesis,
should fail at the 50 MHz speed.

Anyhow, it might be worth a try.


> I also have some sort of a lightdm or related problem. Both pi's have the 
> latest firmware update in them now, and both now boot to a medium grey 
> blank screen, BUT I do have a movable  mouse pointer, and a right click 
> on the mouse brings up a menu, from which I can call up a terminal 
> session, and gfx stuff, run from the cli, works just as if I had a full 
> blown x-server, so thats head scratcher #2 ATM.

Ah, the beautiful headaches X can give you (sorry about the sarcasm). It
seems here that your X session is not started properly.


> What should I do next?

Try and try again?

;-)

-- 
Greetings Bertho

(disclaimers are disclaimed)

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Re: [Emc-users] CC-Link emc2

[Gene Heskett]

On Saturday 27 May 2017 01:49:49 Erik Christiansen wrote:

> On 27.05.17 00:01, Gene Heskett wrote:
> > On Friday 26 May 2017 23:22:41 Erik Christiansen wrote:
> > > Erik
> > > (Who's carted some bricks, and quartered a small Blackwood log
> > > with the chainsaw today, so will pass on the extra exercise.)
> >
> > Blackwood? Oh wait, your are an Aussie IIRC.  Is that a kin of
> > Ebony? Dry, sawdust like sand, fine grained, mills to a high polish
> > if your tooling is sharp.
>
> Now I wish it were, but then I'd have to stand in a queue for the
> trees which came down along the street in the last storm, instead of
> having them to myself. I just have to beat the ones who'd cut it up
> for firewood, but they fortunately don't favour green timber.
>
> > I am wondering if it could be used in place of Ebony, which is from
> > Gabon, Africa, and about $150 a board foot here in the states for a
> > pretty solid black. Getting it past customs takes more weight in
> > paper than the square foot weighs.  Chain of evidence type of thing.
>
> This stuff is actually dark brown, like walnut, though nearly black on
> the end grain when freshly felled. The sapwood is white. Wikipedia
> also likens it to walnut, then says it is now used as a substitute for
> koa. I've used it for interior balustrading, and plan to make some
> modular bookshelves.

Interesting description.  But I've never had a piece of koa to assess its 
beauty, or lack thereof.  Wood beauty is I've observed, in the eye of 
the beerholder. :) So what I think is a beautiful wood may be ugly to 
the next observer.  I am in love with a now rare, beatles have killed 
all the local examples, white ash. So I've collected, as I've stumbled 
over it, quite a bit of it, some of it drying in the woodshed for a 
decade now, and some 2x8's bolted down flat in a steel frame standing in 
a corner in the machine shed.  The steel never quits pulling on it, and 
I could probably go unbolt it today and have it dead flat by a couple 
passes over my jointer.  It spent a decade under black plastic that has 
since gone away, behind the machinery barn at the wifes nieces dairy 
farm up in New York where Rusty had it milled and piled it up but found 
it had warped and wound pretty bad when he went to use it as framing for 
something, so he didn't mind when I abscounded with 200 or 300 pounds of 
it in our trips to see them.  Very strong, and IMO quite striking when 
made into furniture and finished with clear oil.  And it doesn't seem to 
age yellow either.

I'm fond of maple and cherry too, but you've got to grab cherry as soon 
as the wind takes it down, it does not last long laying on the ground.  
Starts to turn mushy in 6 months.  Vacuum dried maple makes good 
gunstocks, but the vacuum needs to be held for a year or so.

> (Once I've finished the house plans¹ which I 
> refuse to pay an architect $6k to draw up, built the new house,
> renovated this one and sold it, and moved all my klamotten out there.)
>
> ¹ Don't tell anyone that I've nearly finished drawing them up via text
>   input in the Postscript language. I find GUIs perverse unintuitive
>   undocumented atrocities, and can't abide the learning curve. With a
>   documented language, I'm in the driver's seat, rather than at the
> back of the bus, constrained and thwarted by all the upholstery in the
> way. I've defined doors, windows, etc, which auto-abut graphically, so
> a wall can be textually created as a list of dimensioned components.
> No rat-wrangling required, either.
>
> Erik


Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page 

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