[Emc-users] nother probably silly Q

[Gene Heskett]

Greetings all;

This vfd somehow has the ability to save and restore its configuration 
data but the wording is quite ambiguous as to where its stored. 
Internally or externally in the controlling host pc. It uses the 
phrase "digital operator" which could translate to its own front panel.

Since I'm using a 5i25 driving a 7i76D, I fail to visualize a host com 
method that doesn't use the RS485/modbus port. Which I don't think I am 
going to try and use.

Is there some other way this might be possible? Or should I just ignore 
this chapter?

I'm concerned because poking the wrong sequence of front panel buttons 
could put it in the recall mode and any bad but stored random data could 
screw the moose.

I assume that config changes are retained over a powerdown as having to 
refresh its settings at every power-up is a complete non-starter to me.

Has anyone else any experience to share with this YL620 family of 
inverters covering the 1.5kw to 3kw range of applications at a source 
voltage range of 110 and 220 volts?.

Thanks all.

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] Hardware emcmot?

[bari]

My dream would be "broadcon" going out of business ending all the Rpi crap.

A big bag of cash falling from the sky over all the LCNC devs homes.

Someone putting effort into 4+ axis open source CAM or other useful
software.

On 4/11/19 7:42 PM, Danny Miller wrote:
> Well, what I would ideally picture is a realtime hardware motion
> controlled coupled to a Raspberry PI running Linux non-RT, the PI is
> hooked to a PC and has an embedded http server.  At that point you
> access it via browser and load and control control your job from the
> PC interface.  estop etc is still on the hardware.  At that point it
> does not matter if you use Windows or Linux.
>
> Danny
>
> On 4/11/2019 7:19 PM, bari wrote:
>> I disagree. The problem is making the machine configuration easy. If
>> LCNC ran on Winders or Androids, many would still complain about how
>> difficult it is to configure. Active High vs Low for Limit switches,
>> Home switches, Step and Dir signals, encoder pulses per rev. etc etc is
>> far to challenging for many to deal with.
>>
>> On 4/11/19 2:41 PM, Chris Albertson wrote:
>>> If the machine controler could run on a me=aintstream OS (like
>>> Windows 10)
>>> and on a normal notebook PC it would be orders of magnitude more
>>> popular
>>> and widly used
>>
>>
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Re: [Emc-users] Hardware emcmot?

[Danny Miller]

Well, what I would ideally picture is a realtime hardware motion 
controlled coupled to a Raspberry PI running Linux non-RT, the PI is 
hooked to a PC and has an embedded http server.  At that point you 
access it via browser and load and control control your job from the PC 
interface.  estop etc is still on the hardware.  At that point it does 
not matter if you use Windows or Linux.


Danny

On 4/11/2019 7:19 PM, bari wrote:

I disagree. The problem is making the machine configuration easy. If
LCNC ran on Winders or Androids, many would still complain about how
difficult it is to configure. Active High vs Low for Limit switches,
Home switches, Step and Dir signals, encoder pulses per rev. etc etc is
far to challenging for many to deal with.

On 4/11/19 2:41 PM, Chris Albertson wrote:

If the machine controler could run on a me=aintstream OS (like Windows 10)
and on a normal notebook PC it would be orders of magnitude more popular
and widly used



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Re: [Emc-users] For PCW

[Danny Miller]

I have used an RS232-to-RS485 adapter and just plugged it into the PC 
serial port.  It was not ideal to add another cable from the PC but it 
works fine.  There are MODBUS drivers for LinuxCNC.


Danny

On 4/11/2019 5:30 PM, Peter C. Wallace wrote:

On Thu, 11 Apr 2019, Gene Heskett wrote:


Date: Thu, 11 Apr 2019 17:56:45 -0400
From: Gene Heskett 
Reply-To: "Enhanced Machine Controller (EMC)"
    
To: "Enhanced Machine Controller (EMC)" 


Subject: [Emc-users] For PCW

Greetings Peter;

The new vfd materialized here today, and I see it actually has what it
calls an RS485 interface, a teeny little white 3 pin socket on its
motherboard.

And I have one or two 422 to 485 translators, the $2 variety, that I
believe are duplex capable as I had to wire them to a solid logic level
on the 5i25 end of them before they would take the balanced signals from
the encoder I put on the spindle motor of my G0704, and make nice 5 volt
rail to rail square waves to feed the 5i25.

If I jury rig the separate 422 lines end of that to the 422 terminals on
that 7i76D, can I talk to a huan yueng lookalike?  That is what I
supposedly bought but the instruction booklet makes no brand claims.

It is a YL-620-A, and it also has the usual analog interface too.
It claims no ascii, but supports the modbus RTU protocol, and mentions
modbus several times..  Am I better off useing the analog, or is the
RS-485 the better control?

Unfortunately you cannot do this currently since MODBUS is not 
supported by the Hostmot2 UART driver



Analog control may be better for things like rigid tapping since the 
normal MODBUS driver is a userland task (and I'm not sure how real 
time the MODBUS implementation in the VFD is.



I also see an AO output, but its reads like 0-5 volts, which doesn't
sound like it would work to indicate the achieved speed via one of the
A/D's on the 7i76D when the 7i76 goes to about 38 volts full scale.



If you have a spindle encoder, that a better way to get speed feedback

This is the first vfd I've had that actually has braking R terminals, 
and

says optional, but if used s/b 100 ohms, 100 watt.  What advantage would
hooking one of those up amount to?



Fater slow-down and faster reversals if tapping (better control of depth)


Thanks for any advice Peter.

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] Hardware emcmot?

[bari]

I have been designing with x86 since the early 80's, ARM since the early
90's and several other architectures (Mips, Sparc, Alpha etc) over the
years. I just don't get the recent attraction to moving the realtime out
of the PC and onto ARM. It's lots of work for what actual benefit? This
idea has come up a lot without anyone really putting any effort into it
besides machinekit. But they picked a SOC without a GPU powerful enough
to run a GUI in HD. Does/did one of them work for TI or something?

On 4/10/19 2:01 PM, Sam Sokolik wrote:
> I don't understand the want to move the realtime stuff out of the
> computer.  What shortcoming are you wanting to solve?  I have not had a
> problem with computer hardware performing the real time parts.  Now that
> rt_preempt is getting mainlined into the kernel - it can only get better.
> I have even had quite a few laptops now that perform quite well.  The
> amount of work that would be required to duplicate the flexibility/ease of
> use of motion/hal in hardware would be a ton.
>
> sam
>
> On Wed, Apr 10, 2019 at 1:48 PM andy pugh  wrote:
>
>> On Wed, 10 Apr 2019 at 19:43,  wrote:
>>
>>> Actually I *don't* want to run a form of Linux. Since it's
>> dedicated
>>> HW, the tasks can be hardcoded for bare metal
>> I wonder if the Mesa "SoftDMC" would do what you want?
>>
>>
>> http://store.mesanet.com/index.php?route=product/product=65_id=163
>>
>>
>> --
>> 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] Hardware emcmot?

[bari]

I disagree. The problem is making the machine configuration easy. If
LCNC ran on Winders or Androids, many would still complain about how
difficult it is to configure. Active High vs Low for Limit switches,
Home switches, Step and Dir signals, encoder pulses per rev. etc etc is
far to challenging for many to deal with.

On 4/11/19 2:41 PM, Chris Albertson wrote:
> If the machine controler could run on a me=aintstream OS (like Windows 10)
> and on a normal notebook PC it would be orders of magnitude more popular
> and widly used



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Re: [Emc-users] For PCW

[Gene Heskett]

On Thursday 11 April 2019 18:30:12 Peter C. Wallace wrote:

> On Thu, 11 Apr 2019, Gene Heskett wrote:
> > Date: Thu, 11 Apr 2019 17:56:45 -0400
> > From: Gene Heskett 
> > Reply-To: "Enhanced Machine Controller (EMC)"
> > 
> > To: "Enhanced Machine Controller (EMC)"
> >  Subject: [Emc-users] For PCW
> >
> > Greetings Peter;
> >
> > The new vfd materialized here today, and I see it actually has what
> > it calls an RS485 interface, a teeny little white 3 pin socket on
> > its motherboard.
> >
> > And I have one or two 422 to 485 translators, the $2 variety, that I
> > believe are duplex capable as I had to wire them to a solid logic
> > level on the 5i25 end of them before they would take the balanced
> > signals from the encoder I put on the spindle motor of my G0704, and
> > make nice 5 volt rail to rail square waves to feed the 5i25.
> >
> > If I jury rig the separate 422 lines end of that to the 422
> > terminals on that 7i76D, can I talk to a huan yueng lookalike?  That
> > is what I supposedly bought but the instruction booklet makes no
> > brand claims.
> >
> > It is a YL-620-A, and it also has the usual analog interface too.
> > It claims no ascii, but supports the modbus RTU protocol, and
> > mentions modbus several times..  Am I better off useing the analog,
> > or is the RS-485 the better control?
>
> Unfortunately you cannot do this currently since MODBUS is not
> supported by the Hostmot2 UART driver.
>
That settles that then, thank you Peter.
>
> Analog control may be better for things like rigid tapping since the
> normal MODBUS driver is a userland task (and I'm not sure how real
> time the MODBUS implementation in the VFD is.

Rigid tapping takes 2 things, an encoder, and 40x the torque.

> > I also see an AO output, but its reads like 0-5 volts, which doesn't
> > sound like it would work to indicate the achieved speed via one of
> > the A/D's on the 7i76D when the 7i76 goes to about 38 volts full
> > scale.
>
> If you have a spindle encoder, that a better way to get speed feedback

That would take something there's no room for. ER20 collet. What little 
room may get used by a hack-a-day pattern of tool changer because it 
will need a solenoid driven wrench to lock the spindle.

> > This is the first vfd I've had that actually has braking R
> > terminals, and says optional, but if used s/b 100 ohms, 100 watt. 
> > What advantage would hooking one of those up amount to?
>
> Faster slow-down and faster reversals if tapping.

which I won't be doing.

> > Thanks for any advice Peter.

Thank you Peter.

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] For PCW

[Peter C. Wallace]

On Thu, 11 Apr 2019, Gene Heskett wrote:


Date: Thu, 11 Apr 2019 17:56:45 -0400
From: Gene Heskett 
Reply-To: "Enhanced Machine Controller (EMC)"

To: "Enhanced Machine Controller (EMC)" 
Subject: [Emc-users] For PCW

Greetings Peter;

The new vfd materialized here today, and I see it actually has what it
calls an RS485 interface, a teeny little white 3 pin socket on its
motherboard.

And I have one or two 422 to 485 translators, the $2 variety, that I
believe are duplex capable as I had to wire them to a solid logic level
on the 5i25 end of them before they would take the balanced signals from
the encoder I put on the spindle motor of my G0704, and make nice 5 volt
rail to rail square waves to feed the 5i25.

If I jury rig the separate 422 lines end of that to the 422 terminals on
that 7i76D, can I talk to a huan yueng lookalike?  That is what I
supposedly bought but the instruction booklet makes no brand claims.

It is a YL-620-A, and it also has the usual analog interface too.
It claims no ascii, but supports the modbus RTU protocol, and mentions
modbus several times..  Am I better off useing the analog, or is the
RS-485 the better control?

Unfortunately you cannot do this currently since MODBUS is not supported by 
the Hostmot2 UART driver



Analog control may be better for things like rigid tapping since the normal 
MODBUS driver is a userland task (and I'm not sure how real time the MODBUS 
implementation in the VFD is.



I also see an AO output, but its reads like 0-5 volts, which doesn't
sound like it would work to indicate the achieved speed via one of the
A/D's on the 7i76D when the 7i76 goes to about 38 volts full scale.



If you have a spindle encoder, that a better way to get speed feedback


This is the first vfd I've had that actually has braking R terminals, and
says optional, but if used s/b 100 ohms, 100 watt.  What advantage would
hooking one of those up amount to?



Fater slow-down and faster reversals if tapping (better control of depth)


Thanks for any advice Peter.

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] Hardware emcmot?

[Gene Heskett]

On Thursday 11 April 2019 15:41:15 Chris Albertson wrote:

> I have to agree,   The entire point of moving al real time functions
> to hardware is so that a real-time OS is no longer required.
>
> The only reason Linux is even needed is that it is an easy way to get
> a real-time OS.   If not for the RT requirement you could use a Mac or
> Windows or even an iPad or any cell phone.
>
> If the machine controler could run on a me=aintstream OS (like Windows
> 10) and on a normal notebook PC it would be orders of magnitude more
> popular and widly used
>
> "EMC" as it was called (then later Linux CNC and then MK) was a great
> idea: Use existing, low cost off the shelf hardware to control a CNC
> machine. This is still a good a very idea but today the existing
> low-cost hardware looks like an STM32 chip and cost about $5.   These
> chips have "compute power" roughly the same as the old PCs EMC was
> developed with.  These little chips are nice to use not just because
> of the price but because there typically come with an RT operating
> system (based on CMSIS)  that has much better RT performance than any
> RT-Linux.
>
Even th D-525-MW motherboard? I can latency-test for an hour or 2 on this 
machine I'm building up right now, and not show any worse than 5.1 
microseconds for base thread latency, and If I run without that thread, 
which I don't use anyway, and the worst case latency is 4850ns.  Thats 
right alongside the figures I've seen quoted for the STM-32.

> There is nothing special about Linux other than it provided a cheap
> and easy to get RT OS.

And security. Windows may be improving, but connected directly to the 
net, how long before its owned. I went from amiga to linux in 1998, and 
have not been touched since. That of course includes using another linux 
product, dd-wrt, between my local network, and the network at large on 
the other side of my cable modem.

> The CMSIS based RTOSes on STM32 are better.   
> I have some experience with both ways and believe by moving to the
> smaller RT system is nearly Arduino-like simplicity and ease of use.  
> I'm using it for robotic motion control now.
>
> On Thu, Apr 11, 2019 at 3:32 AM Les Newell 
>
> wrote:
> > >   Actually I *don't* want to run a form of Linux.
> >
> > I suggested running a Linux variant because it would simplify
> > porting code. Most HAL code only uses a few system calls so you
> > could emulate those calls. IMHO rewriting everything to run on
> > dedicated hardware is a bad idea. Not having compatibility with the
> > main LinuxCNC code base will mean you have to maintain all of the
> > code by yourself. That is a lot of work.
> >
> > > Since it's dedicated
> > > HW, the tasks can be hardcoded for bare metal and stored in flash
> > > and directly load the STEP/DIR pins with SPI data which does
> > > precise, synchronized step-outs.. This is leaner, simpler, more
> > > reliable and the latency can be very low and consistent (although
> > > LinuxCNC on Preempt-RT is already all of that for my machine).
> >
> > If you are just concerned with accurate steps then just move step
> > generation to external hardware. The trajectory planning etc is done
> > at a relatively low speed (usually 1ms intervals) and even a few
> > hundred microseconds of jitter isn't a big deal so there is nothing
> > much to gain in moving this to dedicated hardware. The Ethernet Mesa
> > boards work this way. They use hardware step generation that is
> > updated every 1ms over Ethernet.
> >
> > > This would require somewhat extensive modification of code.
> > > Microcontrollers typically use C and cannot handle C++'s OOP nor
> > > dynamic memory allocation.
> >
> > This is a myth. Even the lowly 8 bit ATMEGA series is fine running
> > OOP C++. Look at Arduino. The majority of that code is C++. Several
> > years ago I wrote a preemptive+cooperative multi tasking real time
> > OS in C++ and it ran well on an ATMEGA. On more memory restricted
> > parts you need to be careful with dynamic memory allocation but it
> > still works as long as you don't go overboard. If you're considering
> > moving emcmot etc to another processor you're gonna need something
> > with considerably more grunt than an ATMEGA anyway.
> >
> > Les


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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[Emc-users] For PCW

[Gene Heskett]

Greetings Peter;

The new vfd materialized here today, and I see it actually has what it 
calls an RS485 interface, a teeny little white 3 pin socket on its 
motherboard.

And I have one or two 422 to 485 translators, the $2 variety, that I 
believe are duplex capable as I had to wire them to a solid logic level 
on the 5i25 end of them before they would take the balanced signals from 
the encoder I put on the spindle motor of my G0704, and make nice 5 volt 
rail to rail square waves to feed the 5i25.

If I jury rig the separate 422 lines end of that to the 422 terminals on 
that 7i76D, can I talk to a huan yueng lookalike?  That is what I 
supposedly bought but the instruction booklet makes no brand claims.

It is a YL-620-A, and it also has the usual analog interface too.
It claims no ascii, but supports the modbus RTU protocol, and mentions 
modbus several times..  Am I better off useing the analog, or is the 
RS-485 the better control?

I also see an AO output, but its reads like 0-5 volts, which doesn't 
sound like it would work to indicate the achieved speed via one of the 
A/D's on the 7i76D when the 7i76 goes to about 38 volts full scale.

This is the first vfd I've had that actually has braking R terminals, and 
says optional, but if used s/b 100 ohms, 100 watt.  What advantage would 
hooking one of those up amount to?

Thanks for any advice Peter.

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] Hardware emcmot?

[Chris Albertson]

I have to agree,   The entire point of moving al real time functions to
hardware is so that a real-time OS is no longer required.

The only reason Linux is even needed is that it is an easy way to get a
real-time OS.   If not for the RT requirement you could use a Mac or
Windows or even an iPad or any cell phone.

If the machine controler could run on a me=aintstream OS (like Windows 10)
and on a normal notebook PC it would be orders of magnitude more popular
and widly used

"EMC" as it was called (then later Linux CNC and then MK) was a great idea:
 Use existing, low cost off the shelf hardware to control a CNC machine.
This is still a good a very idea but today the existing low-cost hardware
looks like an STM32 chip and cost about $5.   These chips have "compute
power" roughly the same as the old PCs EMC was developed with.  These
little chips are nice to use not just because of the price but because
there typically come with an RT operating system (based on CMSIS)  that has
much better RT performance than any RT-Linux.

There is nothing special about Linux other than it provided a cheap and
easy to get RT OS.   The CMSIS based RTOSes on STM32 are better.   I have
some experience with both ways and believe by moving to the smaller RT
system is nearly Arduino-like simplicity and ease of use.   I'm using it
for robotic motion control now.

On Thu, Apr 11, 2019 at 3:32 AM Les Newell 
wrote:

>
> >   Actually I *don't* want to run a form of Linux.
>
> I suggested running a Linux variant because it would simplify porting
> code. Most HAL code only uses a few system calls so you could emulate
> those calls. IMHO rewriting everything to run on dedicated hardware is a
> bad idea. Not having compatibility with the main LinuxCNC code base will
> mean you have to maintain all of the code by yourself. That is a lot of
> work.
>
> > Since it's dedicated
> > HW, the tasks can be hardcoded for bare metal and stored in flash and
> > directly load the STEP/DIR pins with SPI data which does precise,
> > synchronized step-outs.. This is leaner, simpler, more reliable and
> > the latency can be very low and consistent (although LinuxCNC on
> > Preempt-RT is already all of that for my machine).
>
> If you are just concerned with accurate steps then just move step
> generation to external hardware. The trajectory planning etc is done at
> a relatively low speed (usually 1ms intervals) and even a few hundred
> microseconds of jitter isn't a big deal so there is nothing much to gain
> in moving this to dedicated hardware. The Ethernet Mesa boards work this
> way. They use hardware step generation that is updated every 1ms over
> Ethernet.
>
> > This would require somewhat extensive modification of code.
> > Microcontrollers typically use C and cannot handle C++'s OOP nor
> > dynamic memory allocation.
>
> This is a myth. Even the lowly 8 bit ATMEGA series is fine running OOP
> C++. Look at Arduino. The majority of that code is C++. Several years
> ago I wrote a preemptive+cooperative multi tasking real time OS in C++
> and it ran well on an ATMEGA. On more memory restricted parts you need
> to be careful with dynamic memory allocation but it still works as long
> as you don't go overboard. If you're considering moving emcmot etc to
> another processor you're gonna need something with considerably more
> grunt than an ATMEGA anyway.
>
> Les
>
>
> ___
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>


-- 

Chris Albertson
Redondo Beach, California

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Re: [Emc-users] Hardware emcmot?

[Peter C. Wallace]

On Wed, 10 Apr 2019, dan...@austin.rr.com wrote:


Date: Wed, 10 Apr 2019 20:39:06 +
From: dan...@austin.rr.com
Reply-To: "Enhanced Machine Controller (EMC)"

To: "'Enhanced Machine Controller (EMC)'" 
Cc: "'Enhanced Machine Controller (EMC)'" 
Subject: Re: [Emc-users] Hardware emcmot?

From: "andy pugh"
To: "Enhanced Machine Controller (EMC)"
Cc:
Sent: Wednesday April 10 2019 1:46:17PM
Subject: Re: [Emc-users] Hardware emcmot?

On Wed, 10 Apr 2019 at 19:43,  wrote:

> Actually I *don't* want to run a form of Linux. Since it's
dedicated
> HW, the tasks can be hardcoded for bare metal

I wonder if the Mesa "SoftDMC" would do what you want?

-

Hmm maybe so!

Although it is key to modulate beam power at ~5KHz scaled with the
reciprocal of the instantaneous velocity and an accompanying motion
command param. Not the motion command target feedrate but the
instantaneous velocity after acceleration curves are applied. This
prevents burning more energy per inch than specified during accel
periods.

The vector sum is easy to sum squares, but then you have reciprocal
of the square root to create. You know, it doesn't have to be perfect,
I wonder if a polynomial for reciprocal-of-square-root would suffice?
Much faster esp since multiplying 32 bit numbers could in theory
overflow a 32 bit reg (although the velocity to do that seems
unreasonable).

The same is true of any solution, except the bulk 98% of the base
requirement tasks are already there. No nontrapezoidal accel.

There seems to be a lack of arc blending though, and I've seem the
result of poor trajectory planning on certain laser-cut files. Ones
that have like 1000 linear motion commands per inch (that number might
be hyperbole) and poor path smoothing, I think due to pixellation
causing irrelevant right-angle turns for only a few thousandth of an
inch. It ran *really* slow on something that was actually not a whole
lot of exceptionally high detail. Some of that could be path smoothing
approximated in the CAM stage.

Danny

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I notice that you ordered a copy of SoftDMC from our webstore. I suspect This 
is not the best way to accomplish laser modulation with LinuxCNC


If you use our hardware, I think the best way would be to use our DataPainter
module for Hostmot2. Unfortunately this does not have a driver yet but could 
be accessed via raw register access in a real time hal component


This implements a FIFOed data stream (bitstream or PWM) that can be "position 
locked" to a motion axis or a multi-axis length vector for arbitrary path 
painting. In addition it has front-end (realtime) scaling of the PWM so that
PWM duty cycle is the product of FIFO PWM data times real time (probably 
scaled/lincurved velocity) data.


The 1 KHz or so servo thread update rate is not a real limitation here since 
the data painting interpolates between motions (possibly scale) waypoints


Its addition it has start and stop position registers to allow gating the data 
stream at position breakpoints



This will support modulation rates to the hundreds of KHz


Misssing bits in LinuxCNC are some standard scheme to include position
synchronized data either embedded in the gcode or via external files



Peter Wallace
Mesa Electronics


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Re: [Emc-users] Nice manual lathe in WA (assume WA USA not WA AU)

[Jon Elson]

On 04/10/2019 08:42 PM, Tom Easterday wrote:

4 Sheldon lathes being sold in SE Michigan. Short notice but came across this 
by accident and I recalled this thread talking about Sheldon lathes...

https://toledo.craigslist.org/tls/d/temperance-14-sheldon-6-jaw-lathe/6853491715.html

I didn't see 4, but this one is an early model Sheldon R-13 
(13"). Quite heavy duty machine, I have a late model R-15. (15")


Jon


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[Emc-users] Orange Pi Linuxcnc fun with Google Translate in Russian

[TJoseph Powderly]

I haven't translated this, nor tried the code
but maybe its of interest to the group.

Theres a lot of non-english speaking linuxcnc developers,
and the language barriers often hide their efforts,
due to browser and search engine preferences.

https://github.com/orange-cnc
http://orange-cnc.ru/

tomp


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Re: [Emc-users] Hardware emcmot?

[Les Newell]

Actually I *don't* want to run a form of Linux.


I suggested running a Linux variant because it would simplify porting 
code. Most HAL code only uses a few system calls so you could emulate 
those calls. IMHO rewriting everything to run on dedicated hardware is a 
bad idea. Not having compatibility with the main LinuxCNC code base will 
mean you have to maintain all of the code by yourself. That is a lot of 
work.



Since it's dedicated
HW, the tasks can be hardcoded for bare metal and stored in flash and
directly load the STEP/DIR pins with SPI data which does precise,
synchronized step-outs.. This is leaner, simpler, more reliable and
the latency can be very low and consistent (although LinuxCNC on
Preempt-RT is already all of that for my machine).


If you are just concerned with accurate steps then just move step 
generation to external hardware. The trajectory planning etc is done at 
a relatively low speed (usually 1ms intervals) and even a few hundred 
microseconds of jitter isn't a big deal so there is nothing much to gain 
in moving this to dedicated hardware. The Ethernet Mesa boards work this 
way. They use hardware step generation that is updated every 1ms over 
Ethernet.



This would require somewhat extensive modification of code.
Microcontrollers typically use C and cannot handle C++'s OOP nor
dynamic memory allocation.


This is a myth. Even the lowly 8 bit ATMEGA series is fine running OOP 
C++. Look at Arduino. The majority of that code is C++. Several years 
ago I wrote a preemptive+cooperative multi tasking real time OS in C++ 
and it ran well on an ATMEGA. On more memory restricted parts you need 
to be careful with dynamic memory allocation but it still works as long 
as you don't go overboard. If you're considering moving emcmot etc to 
another processor you're gonna need something with considerably more 
grunt than an ATMEGA anyway.


Les


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[Emc-users] upgrading jessie

[TJoseph Powderly]

John Thornton, Hello,
I have a problem upgrading from Debian 8 to Debian 9 ( Jessie to Stretch i
think they are named ).

I followed these notes
https://gnipsel.com/linuxcnc/uspace/debian9-emc.html
I had no errors or warnings until
near the end I got this message
(while installing linuxcnc-uspace)

tomp@jessie:~$ sudo apt-get install linuxcnc-uspace
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 linuxcnc-uspace : Depends: libboost-python1.62.0 but it is not installable
   Depends: libstdc++6 (>= 5.2) but 4.9.2-10+deb8u2 is to
be installed
   Recommends: linux-image-rt-amd64 but it is not
installable
E: Unable to correct problems, you have held broken packages.

i already have libboost-python 1.55   and no 1.6 listed by synaptic
I already have libstdc++ 4.9.2.10+deb8u2 ,
( i have no idea what is meant by "is to be installed" , its already there )

some info about my system:

tomp@jessie:~$ uname -a
Linux jessie 3.16.0-9-rtai-amd64 #1 SMP PREEMPT Debian 3.16.7-6linuxcnc
(2015-11-30) x86_64 GNU/Linux

tomp@jessie:~$ cat /etc/os-release
PRETTY_NAME="Debian GNU/Linux 8 (jessie)"
NAME="Debian GNU/Linux"
VERSION_ID="8"
VERSION="8 (jessie)"
ID=debian
HOME_URL="http://www.debian.org/;
SUPPORT_URL="http://www.debian.org/support;
BUG_REPORT_URL="https://bugs.debian.org/;

any hints?

thanks
tomp

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