Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Feral Engineer]

Then you should have no trouble at all .

I like the wizards, but completely understand where you're coming from with
configuring hal. You can do anything and everything you want with it. On
the flip side, coming from an industry where plc is still king, I love
being able to use classicladder and build circuits that way also. I don't
think CL gets the respect it deserves.

Phil T.
The Feral Engineer

Check out my LinuxCNC tutorials, machine builds and other antics at
www.youtube.com/c/theferalengineer

Help support my channel efforts and coffee addiction:
www.patreon.com/theferalengineer

On Tue, Jun 29, 2021, 9:55 PM Leonardo Marsaglia 
wrote:

> >
> > I helped a guy set up a 7i95 with encoders. Not hard, but not super
> simple
> > because pncconf doesn't support that board native and the 7i95
> configurator
> > didn't work. I used the ini name setting in pncconf, made a config for a
> > 7i96 and had to change the name of the board in the ini file and rename
> the
> > io pins.
> >
> > I have a two switch home setup on my Emco using a prox switch as an index
> > pulse after hitting a mechanical switch, using home_use_index and I'm
> using
> > home_index_no_encoder_reset in master to home my x and z without having
> > full encoder feedback. I made some videos on my YouTube channel about it.
> >
> > I'm not shying you away from the 7i95, i think it's a great board, but be
> > ready for a little hair pulling unless you're pretty comfortable with the
> > mesa ecosystem.
> >
>
> Well, I'm not new to mesa boards but I'm always using a whole different
> approach on each machine. The first I installed was the 5i25 with a
> breakout board my brother already designed for another project. Then I
> started with the PCIe ones, and now I'm finally going for the ethernet ones
> because saves me a lot of hassle mounting the PC on the cabinet. On the top
> of that, I'm retrofitting a machine every 2 years so every time is like I'm
> re learning all of it again.
>
> One thing I must say, I've never used PNCCONF or STEPCONF. What I always
> loved about LCNC is the way I can model a system with HAL using plain text.
> I'm far away from being a programmer but the way HAL works for me is just
> pure genius. I don't even use the Classicladder feature. For me HAL has it
> all right there, and It never ceases to amaze me.
>
> El sáb, 26 jun 2021 a las 10:17, Feral Engineer (<
> theferalengin...@gmail.com>)
> escribió:
>
> > I helped a guy set up a 7i95 with encoders. Not hard, but not super
> simple
> > because pncconf doesn't support that board native and the 7i95
> configurator
> > didn't work. I used the ini name setting in pncconf, made a config for a
> > 7i96 and had to change the name of the board in the ini file and rename
> the
> > io pins.
> >
> > I have a two switch home setup on my Emco using a prox switch as an index
> > pulse after hitting a mechanical switch, using home_use_index and I'm
> using
> > home_index_no_encoder_reset in master to home my x and z without having
> > full encoder feedback. I made some videos on my YouTube channel about it.
> >
> > I'm not shying you away from the 7i95, i think it's a great board, but be
> > ready for a little hair pulling unless you're pretty comfortable with the
> > mesa ecosystem.
> >
> > That being said, anyone ever use a 7i95 for full closed loop to LinuxCNC
> > using step dir and encoders? I know a lot of guys are using the 7i77 that
> > way with analog and there's the 7i97 that would be fun to check out as
> well
> > for analog setups. Curious if there's any kind of weirdness that happens
> > using step pulse with encoder vs just using analog signal.
> >
> >
> > Phil T.
> > The Feral Engineer
> >
> > Check out my LinuxCNC tutorials, machine builds and other antics at
> > www.youtube.com/c/theferalengineer
> >
> > Help support my channel efforts and coffee addiction:
> > www.patreon.com/theferalengineer
> >
> > On Sat, Jun 26, 2021, 8:47 AM Leonardo Marsaglia 
> > wrote:
> >
> > > Hello Andrew and Gene and sorry for the late reply. I hope you're doing
> > > great!
> > >
> > > I believe I'll use the 7i84 as Peter suggested to expand the I/Os. But
> > > instead of the 7i76E I'll go with the 7i95 which can read encoders too.
> > > With this I can replicate what I did on the mazak which is to fool the
> > > homing sequence to use the index pulse of the motors on the final
> stage.
> > >
> > > El mar, 22 jun 2021 a las 2:23, Gene Heskett ()
> > > escribió:
> > >
> > > > On Monday 21 June 2021 22:01:25 Leonardo Marsaglia wrote:
> > > >
> > > > > Thanks a lot Peter and Andy,
> > > > >
> > > > > I re read through the manual and found the SSERIAL port connection
> > and
> > > > > the recommendation of using a CAT5 cable cut in half. I missed that
> > > > > part so I was a little confused about how to expand the I/Os. So,
> > I'll
> > > > > be more than ok with this board :)
> > > > >
> > > > Another possibility if you need lots of i/o, is the 7i90HD, which
> has a
> > > > total 

Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Leonardo Marsaglia]

>
> I helped a guy set up a 7i95 with encoders. Not hard, but not super simple
> because pncconf doesn't support that board native and the 7i95 configurator
> didn't work. I used the ini name setting in pncconf, made a config for a
> 7i96 and had to change the name of the board in the ini file and rename the
> io pins.
>
> I have a two switch home setup on my Emco using a prox switch as an index
> pulse after hitting a mechanical switch, using home_use_index and I'm using
> home_index_no_encoder_reset in master to home my x and z without having
> full encoder feedback. I made some videos on my YouTube channel about it.
>
> I'm not shying you away from the 7i95, i think it's a great board, but be
> ready for a little hair pulling unless you're pretty comfortable with the
> mesa ecosystem.
>

Well, I'm not new to mesa boards but I'm always using a whole different
approach on each machine. The first I installed was the 5i25 with a
breakout board my brother already designed for another project. Then I
started with the PCIe ones, and now I'm finally going for the ethernet ones
because saves me a lot of hassle mounting the PC on the cabinet. On the top
of that, I'm retrofitting a machine every 2 years so every time is like I'm
re learning all of it again.

One thing I must say, I've never used PNCCONF or STEPCONF. What I always
loved about LCNC is the way I can model a system with HAL using plain text.
I'm far away from being a programmer but the way HAL works for me is just
pure genius. I don't even use the Classicladder feature. For me HAL has it
all right there, and It never ceases to amaze me.

El sáb, 26 jun 2021 a las 10:17, Feral Engineer ()
escribió:

> I helped a guy set up a 7i95 with encoders. Not hard, but not super simple
> because pncconf doesn't support that board native and the 7i95 configurator
> didn't work. I used the ini name setting in pncconf, made a config for a
> 7i96 and had to change the name of the board in the ini file and rename the
> io pins.
>
> I have a two switch home setup on my Emco using a prox switch as an index
> pulse after hitting a mechanical switch, using home_use_index and I'm using
> home_index_no_encoder_reset in master to home my x and z without having
> full encoder feedback. I made some videos on my YouTube channel about it.
>
> I'm not shying you away from the 7i95, i think it's a great board, but be
> ready for a little hair pulling unless you're pretty comfortable with the
> mesa ecosystem.
>
> That being said, anyone ever use a 7i95 for full closed loop to LinuxCNC
> using step dir and encoders? I know a lot of guys are using the 7i77 that
> way with analog and there's the 7i97 that would be fun to check out as well
> for analog setups. Curious if there's any kind of weirdness that happens
> using step pulse with encoder vs just using analog signal.
>
>
> Phil T.
> The Feral Engineer
>
> Check out my LinuxCNC tutorials, machine builds and other antics at
> www.youtube.com/c/theferalengineer
>
> Help support my channel efforts and coffee addiction:
> www.patreon.com/theferalengineer
>
> On Sat, Jun 26, 2021, 8:47 AM Leonardo Marsaglia 
> wrote:
>
> > Hello Andrew and Gene and sorry for the late reply. I hope you're doing
> > great!
> >
> > I believe I'll use the 7i84 as Peter suggested to expand the I/Os. But
> > instead of the 7i76E I'll go with the 7i95 which can read encoders too.
> > With this I can replicate what I did on the mazak which is to fool the
> > homing sequence to use the index pulse of the motors on the final stage.
> >
> > El mar, 22 jun 2021 a las 2:23, Gene Heskett ()
> > escribió:
> >
> > > On Monday 21 June 2021 22:01:25 Leonardo Marsaglia wrote:
> > >
> > > > Thanks a lot Peter and Andy,
> > > >
> > > > I re read through the manual and found the SSERIAL port connection
> and
> > > > the recommendation of using a CAT5 cable cut in half. I missed that
> > > > part so I was a little confused about how to expand the I/Os. So,
> I'll
> > > > be more than ok with this board :)
> > > >
> > > Another possibility if you need lots of i/o, is the 7i90HD, which has a
> > > total of 72 lines. Firmware options for uo to 8 axises of steppers and
> > > encoders. Or I believe pwm-gens and encoders. The disadvantages are its
> > > 3, 50 pin i/o's that are all tied to the fpga, and easily damaged by
> > > noise. The fix for that is a trio of 7i42TA's which are effectly used
> as
> > > breakout boards, tradeing some bandwidth for the usual surge protection
> > > and giving you nice screw terminals to wire it up with. It can be
> driven
> > > from an epp parport, or from an spi port from a pi. With all the
> > > gingerbread I've put on the sheldon, I probably have 35 i/o lines
> unused
> > > yet. And I can fire up firefox and browse the net at the same time its
> > > running the sheldon. I felt keeping the ethernet port out of the lcnc
> > > arena, so the net port was available for updating and such was more
> > > important, and still do. 2 of my 4 machines 

Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Gene Heskett]

On Saturday 26 June 2021 12:52:26 John Dammeyer wrote:

> > Also, I'm looking for the secret sauce to get full closed loop from
> > my vfd to LinuxCNC if anyone has pointers on that. I have encoder
> > feedback to LinuxCNC, but i feel like I'm missing a key element to
> > get the pid working properly. Most of the adjustments I've made to
> > pid never result in LinuxCNC compensating for the error (i.e. G97
> > S200 = S210 actual with p =0, changing P results in a runaway in
> > most cases). I'm wondering what the magic net command might be to
> > get everything working so I could thread on my lathe.
> >
> > Phil T.
> > The Feral Engineer

Generally speaking, using the hz from the vfd is a lost cause. Put an 
encoder on the spindle, but be aware that the 3 phase induction motors 
commoly used on lathes and higher powered mills all suffer from 2 
effects at the high hz settings. At 60 hz, the slip angle between the 
rotating field and the armature will give you about 1750 rpm from the 
common 4 pole motor, not 1800. Step the hz up to 120 hz will reduce the 
coil currents because of the motor finite inductance, which combined 
with the higher friction load, will only get you around 3200 revs at the 
motor shaft because the currents are reduced, increasing the slip angle, 
and above 120 hz you will hit a point where no further increase in the 
frequency will gain you speed, and it may well slow down. That occurs at 
less than 180 hz on mine. The pid can tell it to go faster, but the coil 
currants are so low, less than an amp/phase, that its out of torque

This is true for any "induction" motor. The 2 pole for the 24k revs 
motors is more than likely a hard steel armature running synchronously 
with the magnetic fields rotation, but inductance still causes a loss of 
torque at the higher speeds, but if its running, it is probably at the 
right speed.

But those motors don't have the cajones to pull a tap anyway.

I have an encoder on the Sheldon and I can even do rigid tapping on it, 
but the encoder is NOT feeding back to the PID, its only function is 
reporting the spindle's rotational position for G76 and G33.1 functions. 
That it does well given the sloppy machining and uneven wear on the 
tooth edges of the 60 tooth bull gear on the spindle. 

Now, if the PID could be used to raise the voltages out of the vfd at the 
higher speeds in order to keep the coil currents at the FLA value on the 
nameplate, we'ed have something great, but bring wagon loads of money 
for the switching devices in the vfd to achieve that. To my knowledge, 
no one has done that. To make it work at 400hz would take well over 1 
kilovolt from the vfd. Tain't gonna happen. The motors winding 
insulation would fail, sooner rather than later.

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)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Peter C. Wallace]

On Sat, 26 Jun 2021, Gene Heskett wrote:


Date: Sat, 26 Jun 2021 12:51:03 -0400
From: Gene Heskett 
Reply-To: "Enhanced Machine Controller (EMC)"

To: emc-users@lists.sourceforge.net
Subject: Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

On Saturday 26 June 2021 12:17:15 Feral Engineer wrote:


Hey John,

I guess i should've explained better, I was half awake when I asked
that. I'm running dmm servos on my mill, which are currently driven on
a 7i76e with step/dir and are only semi closed loop (closed loop from
the motor to the drive, but not to LinuxCNC). I'm Curious if it's
possible to use the external encoder feedback from the dyn4 to
LinuxCNC to create a full closed loop arrangement using that encoder
and step/dir or do the servos have to be controlled via analog signal
and pid tuning to get the encoder feedback to be closed loop?

Also, I'm looking for the secret sauce to get full closed loop from my
vfd to LinuxCNC if anyone has pointers on that. I have encoder
feedback to LinuxCNC, but i feel like I'm missing a key element to get
the pid working properly. Most of the adjustments I've made to pid
never result in LinuxCNC compensating for the error (i.e. G97 S200 =
S210 actual with p =0, changing P results in a runaway in most cases).
I'm wondering what the magic net command might be to get everything
working so I could thread on my lathe.



Phil T.
The Feral Engineer


Exchange the A & B signals from the encoder to LCNC, either in the .hal
file, or physically, it sounds as if the LCNC PID thinks its running
backwards. Check for sure by watching the encoder output with a
halmeter, it should be counting up when the motor is turning fwd, and
vice-versa.

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)
If we desire respect for the law, we must first make the law respectable.
- Louis D. Brandeis
Genes Web page <http://geneslinuxbox.net:6309/gene>


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Also the hal connections or encoder scaling of the PID feedback signal may be 
wrong. Check the PID feedback value, it should be close to the commanded value.



Peter Wallace
Mesa Electronics


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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[John Dammeyer]

Hi Phil,
Lots of people run the closed loop with the spindle and pwm and encoder.  If 
you add P and it runs away odds are your encoder polarity on A/B is backwards.  
Switch A for B and then try it.  

As I understand the LinuxCNC approach to threading (unlike MACH3 and my ELS 
which use 1PPR) the index is used to 'know' where the start of the thread is 
and the A input of the encoder tracks the spindle speed to ensure the leadscrew 
and spindle stay synchronized.  I would imagine if you have both A and B 
connected that then the direction of the spindle is known and if it's going the 
wrong way (from the LinuxCNC perspective) nothing will work.

Not sure I'd agree with the term semi-closed loop between motor and drive.  If 
the motor has an encoder and the drive uses that then it's fully closed loop.  
The tuning is then done with the PID and FF pins inside the drive.  Adding 
another control loop outside that may well result in an unstable or very 
difficult to tune system.  As it is PID can be difficult to tune.

I have HP_UHU drivers on my DC Brushed servos.   They have all the bells and 
whistles for things like following error etc and a fault output that will shut 
down motion if the encoder exceeds the encoder count range.  I don't think that 
it can be improved upon by adding LinuxCNC control.
Here's a short article on them.  
https://www.henriksplace.se/cnc/abene_4_3.html
Henrik has since also created a PIC based clone of the original ATMEL processor 
with the ability to handle much higher resolution encoders etc.  It plugs into 
the ATMEL processor socket
 
My Knee has a 750W Bergerda AC Servo with 3.2:1 pulleys and can run 150 ipm 
which is way too fast for the heavy knee, bevel gears and ACME leadscrew.   
I've designed a rotating ball screw arrangement but it's way down the todo 
list; project #42.

And I'm running the STMBL AC servo drive on the Harmonic Drive Rotary axis.  
This still needs finishing and is also project #42.

John


> -Original Message-
> From: Feral Engineer [mailto:theferalengin...@gmail.com]
> Sent: June-26-21 9:17 AM
> To: Enhanced Machine Controller (EMC)
> Subject: Re: [Emc-users] About the 7i76E and possible DB25 expansion cards
> 
> Hey John,
> 
> I guess i should've explained better, I was half awake when I asked that.
> I'm running dmm servos on my mill, which are currently driven on a 7i76e
> with step/dir and are only semi closed loop (closed loop from the motor to
> the drive, but not to LinuxCNC). I'm Curious if it's possible to use the
> external encoder feedback from the dyn4 to LinuxCNC to create a full closed
> loop arrangement using that encoder and step/dir or do the servos have to
> be controlled via analog signal and pid tuning to get the encoder feedback
> to be closed loop?
> 
> Also, I'm looking for the secret sauce to get full closed loop from my vfd
> to LinuxCNC if anyone has pointers on that. I have encoder feedback to
> LinuxCNC, but i feel like I'm missing a key element to get the pid working
> properly. Most of the adjustments I've made to pid never result in LinuxCNC
> compensating for the error (i.e. G97 S200 = S210 actual with p =0, changing
> P results in a runaway in most cases). I'm wondering what the magic net
> command might be to get everything working so I could thread on my lathe.
> 
> Phil T.
> The Feral Engineer
> 
> Check out my LinuxCNC tutorials, machine builds and other antics at
> www.youtube.com/c/theferalengineer
> 
> Help support my channel efforts and coffee addiction:
> www.patreon.com/theferalengineer
> 
> On Sat, Jun 26, 2021, 11:46 AM John Dammeyer  wrote:
> 
> > > That being said, anyone ever use a 7i95 for full closed loop to LinuxCNC
> > > using step dir and encoders? I know a lot of guys are using the 7i77 that
> > > way with analog and there's the 7i97 that would be fun to check out as
> > well
> > > for analog setups. Curious if there's any kind of weirdness that happens
> > > using step pulse with encoder vs just using analog signal.
> > >
> > >
> > > Phil T.
> > > The Feral Engineer
> >
> > Hi Phil,
> > On the bench I have the Pi4 driving the Bergerda AC Servo spindle with
> > step/dir  (smaller motor for bench testing) with an encoder coupled back
> > for feedback.  At the moment I have P=0 and FF1=0 so I'm not using closed
> > loop control because it would probably fight with the Bergerda which has
> > its own set of PID parameters.
> >
> > I not sure you can really do that with a real stepper motor because at
> > high speeds once the motor loses position it locks up and you need to slow
> > down the step rate to get it to mechanically synchronize.  For final
> > positioning though, since a stepper is only accurate to the nearest full

Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Gene Heskett]

On Saturday 26 June 2021 12:17:15 Feral Engineer wrote:

> Hey John,
>
> I guess i should've explained better, I was half awake when I asked
> that. I'm running dmm servos on my mill, which are currently driven on
> a 7i76e with step/dir and are only semi closed loop (closed loop from
> the motor to the drive, but not to LinuxCNC). I'm Curious if it's
> possible to use the external encoder feedback from the dyn4 to
> LinuxCNC to create a full closed loop arrangement using that encoder
> and step/dir or do the servos have to be controlled via analog signal
> and pid tuning to get the encoder feedback to be closed loop?
>
> Also, I'm looking for the secret sauce to get full closed loop from my
> vfd to LinuxCNC if anyone has pointers on that. I have encoder
> feedback to LinuxCNC, but i feel like I'm missing a key element to get
> the pid working properly. Most of the adjustments I've made to pid
> never result in LinuxCNC compensating for the error (i.e. G97 S200 =
> S210 actual with p =0, changing P results in a runaway in most cases).
> I'm wondering what the magic net command might be to get everything
> working so I could thread on my lathe.

> Phil T.
> The Feral Engineer

Exchange the A & B signals from the encoder to LCNC, either in the .hal 
file, or physically, it sounds as if the LCNC PID thinks its running 
backwards. Check for sure by watching the encoder output with a 
halmeter, it should be counting up when the motor is turning fwd, and 
vice-versa.

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)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Gene Heskett]

On Saturday 26 June 2021 11:43:12 John Dammeyer wrote:

> > That being said, anyone ever use a 7i95 for full closed loop to
> > LinuxCNC using step dir and encoders? I know a lot of guys are using
> > the 7i77 that way with analog and there's the 7i97 that would be fun
> > to check out as well for analog setups. Curious if there's any kind
> > of weirdness that happens using step pulse with encoder vs just
> > using analog signal.
> >
> >
> > Phil T.
> > The Feral Engineer
>
> Hi Phil,
> On the bench I have the Pi4 driving the Bergerda AC Servo spindle with
> step/dir  (smaller motor for bench testing) with an encoder coupled
> back for feedback.  At the moment I have P=0 and FF1=0 so I'm not
> using closed loop control because it would probably fight with the
> Bergerda which has its own set of PID parameters.
>
> I not sure you can really do that with a real stepper motor because at
> high speeds once the motor loses position it locks up and you need to
> slow down the step rate to get it to mechanically synchronize.  For
> final positioning though, since a stepper is only accurate to the
> nearest full step position,  an encoder could be used with LinuxCNC to
> add/subtract micro-steps until the motor turned to the encoder
> expected position.
>
> The closed loop servo-steppers work slightly differently I believe.
> (Haven't checked).  I think they treat the two stepper windings as a
> two phase AC motor with the AC waveforms recreated matching the
> encoder resolution.  Or if they are really clever they, like the
> Gecko, would switch to full step square waves after the resonance
> point to raise the torque from 0.707 of name plate to full.  And they
> too would adjust the two phase waveform when stopped to the expected
> encoder position based on step count input.
>
> John Dammeyer
>
Which is why I am in love with the 3 phase stepper servo's just now 
comiing on the market. They combine a 3 phase full step size of 1.2 
degrees with a 1000 line encoder with a power saving citcuit that runs 
the motor dead cold as long as the following error is low. And if pushed 
beyond their ability, have a fault output that stops the machine as 
quick as it can. "home" cannot be lost with these and leave it running.

Currently available in nema 23 at 1NM, 2NM, and 3NM torque's. I have a 6 
pack of 1NM's on order to see if they can run my 6040, one of which will 
go on an all printed harmonic drive to put some precision into the A 
axis supplied with the 6040 if you buy the 4 axis model. But my printed 
version of this drive is only 90mm in diameter, and w/o an output 
sprocket, only 20mm thick. 30/1 gear ratio. Output sprocket still being 
written.

When its all done and working, the openscad file to make it will be 
published. But I've yet to test its longevity, I've not yet obtained the 
screws to mount it with, which I think will be good. 1st one is made of 
PLA, next one if needed from carbon fiber PETG.

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)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Feral Engineer]

Hey John,

I guess i should've explained better, I was half awake when I asked that.
I'm running dmm servos on my mill, which are currently driven on a 7i76e
with step/dir and are only semi closed loop (closed loop from the motor to
the drive, but not to LinuxCNC). I'm Curious if it's possible to use the
external encoder feedback from the dyn4 to LinuxCNC to create a full closed
loop arrangement using that encoder and step/dir or do the servos have to
be controlled via analog signal and pid tuning to get the encoder feedback
to be closed loop?

Also, I'm looking for the secret sauce to get full closed loop from my vfd
to LinuxCNC if anyone has pointers on that. I have encoder feedback to
LinuxCNC, but i feel like I'm missing a key element to get the pid working
properly. Most of the adjustments I've made to pid never result in LinuxCNC
compensating for the error (i.e. G97 S200 = S210 actual with p =0, changing
P results in a runaway in most cases). I'm wondering what the magic net
command might be to get everything working so I could thread on my lathe.

Phil T.
The Feral Engineer

Check out my LinuxCNC tutorials, machine builds and other antics at
www.youtube.com/c/theferalengineer

Help support my channel efforts and coffee addiction:
www.patreon.com/theferalengineer

On Sat, Jun 26, 2021, 11:46 AM John Dammeyer  wrote:

> > That being said, anyone ever use a 7i95 for full closed loop to LinuxCNC
> > using step dir and encoders? I know a lot of guys are using the 7i77 that
> > way with analog and there's the 7i97 that would be fun to check out as
> well
> > for analog setups. Curious if there's any kind of weirdness that happens
> > using step pulse with encoder vs just using analog signal.
> >
> >
> > Phil T.
> > The Feral Engineer
>
> Hi Phil,
> On the bench I have the Pi4 driving the Bergerda AC Servo spindle with
> step/dir  (smaller motor for bench testing) with an encoder coupled back
> for feedback.  At the moment I have P=0 and FF1=0 so I'm not using closed
> loop control because it would probably fight with the Bergerda which has
> its own set of PID parameters.
>
> I not sure you can really do that with a real stepper motor because at
> high speeds once the motor loses position it locks up and you need to slow
> down the step rate to get it to mechanically synchronize.  For final
> positioning though, since a stepper is only accurate to the nearest full
> step position,  an encoder could be used with LinuxCNC to add/subtract
> micro-steps until the motor turned to the encoder expected position.
>
> The closed loop servo-steppers work slightly differently I believe.
> (Haven't checked).  I think they treat the two stepper windings as a two
> phase AC motor with the AC waveforms recreated matching the encoder
> resolution.  Or if they are really clever they, like the Gecko, would
> switch to full step square waves after the resonance point to raise the
> torque from 0.707 of name plate to full.  And they too would adjust the two
> phase waveform when stopped to the expected encoder position based on step
> count input.
>
> John Dammeyer
>
>
>
>
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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[John Dammeyer]

> That being said, anyone ever use a 7i95 for full closed loop to LinuxCNC
> using step dir and encoders? I know a lot of guys are using the 7i77 that
> way with analog and there's the 7i97 that would be fun to check out as well
> for analog setups. Curious if there's any kind of weirdness that happens
> using step pulse with encoder vs just using analog signal.
> 
> 
> Phil T.
> The Feral Engineer

Hi Phil,
On the bench I have the Pi4 driving the Bergerda AC Servo spindle with step/dir 
 (smaller motor for bench testing) with an encoder coupled back for feedback.  
At the moment I have P=0 and FF1=0 so I'm not using closed loop control because 
it would probably fight with the Bergerda which has its own set of PID 
parameters.  

I not sure you can really do that with a real stepper motor because at high 
speeds once the motor loses position it locks up and you need to slow down the 
step rate to get it to mechanically synchronize.  For final positioning though, 
since a stepper is only accurate to the nearest full step position,  an encoder 
could be used with LinuxCNC to add/subtract micro-steps until the motor turned 
to the encoder expected position.

The closed loop servo-steppers work slightly differently I believe. (Haven't 
checked).  I think they treat the two stepper windings as a two phase AC motor 
with the AC waveforms recreated matching the encoder resolution.  Or if they 
are really clever they, like the Gecko, would switch to full step square waves 
after the resonance point to raise the torque from 0.707 of name plate to full. 
 And they too would adjust the two phase waveform when stopped to the expected 
encoder position based on step count input.

John Dammeyer
 



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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Feral Engineer]

I helped a guy set up a 7i95 with encoders. Not hard, but not super simple
because pncconf doesn't support that board native and the 7i95 configurator
didn't work. I used the ini name setting in pncconf, made a config for a
7i96 and had to change the name of the board in the ini file and rename the
io pins.

I have a two switch home setup on my Emco using a prox switch as an index
pulse after hitting a mechanical switch, using home_use_index and I'm using
home_index_no_encoder_reset in master to home my x and z without having
full encoder feedback. I made some videos on my YouTube channel about it.

I'm not shying you away from the 7i95, i think it's a great board, but be
ready for a little hair pulling unless you're pretty comfortable with the
mesa ecosystem.

That being said, anyone ever use a 7i95 for full closed loop to LinuxCNC
using step dir and encoders? I know a lot of guys are using the 7i77 that
way with analog and there's the 7i97 that would be fun to check out as well
for analog setups. Curious if there's any kind of weirdness that happens
using step pulse with encoder vs just using analog signal.


Phil T.
The Feral Engineer

Check out my LinuxCNC tutorials, machine builds and other antics at
www.youtube.com/c/theferalengineer

Help support my channel efforts and coffee addiction:
www.patreon.com/theferalengineer

On Sat, Jun 26, 2021, 8:47 AM Leonardo Marsaglia 
wrote:

> Hello Andrew and Gene and sorry for the late reply. I hope you're doing
> great!
>
> I believe I'll use the 7i84 as Peter suggested to expand the I/Os. But
> instead of the 7i76E I'll go with the 7i95 which can read encoders too.
> With this I can replicate what I did on the mazak which is to fool the
> homing sequence to use the index pulse of the motors on the final stage.
>
> El mar, 22 jun 2021 a las 2:23, Gene Heskett ()
> escribió:
>
> > On Monday 21 June 2021 22:01:25 Leonardo Marsaglia wrote:
> >
> > > Thanks a lot Peter and Andy,
> > >
> > > I re read through the manual and found the SSERIAL port connection and
> > > the recommendation of using a CAT5 cable cut in half. I missed that
> > > part so I was a little confused about how to expand the I/Os. So, I'll
> > > be more than ok with this board :)
> > >
> > Another possibility if you need lots of i/o, is the 7i90HD, which has a
> > total of 72 lines. Firmware options for uo to 8 axises of steppers and
> > encoders. Or I believe pwm-gens and encoders. The disadvantages are its
> > 3, 50 pin i/o's that are all tied to the fpga, and easily damaged by
> > noise. The fix for that is a trio of 7i42TA's which are effectly used as
> > breakout boards, tradeing some bandwidth for the usual surge protection
> > and giving you nice screw terminals to wire it up with. It can be driven
> > from an epp parport, or from an spi port from a pi. With all the
> > gingerbread I've put on the sheldon, I probably have 35 i/o lines unused
> > yet. And I can fire up firefox and browse the net at the same time its
> > running the sheldon. I felt keeping the ethernet port out of the lcnc
> > arena, so the net port was available for updating and such was more
> > important, and still do. 2 of my 4 machines are building and installig
> > their own versions of linuxcnc from github master-gtk3 as I type this,
> > including that rpi4.
> >
> > > El lun, 21 jun 2021 a las 4:45, andy pugh ()
> > escribió:
> > > > On Mon, 21 Jun 2021 at 03:27, Leonardo Marsaglia
> > > > 
> > > >
> > > > wrote:
> > > > > Is the 7i75
> > > > > breakout board the way to add more I/Os to the 7i76E? And in that
> > > > > case I suppose the direction of the I/O pins in determined in HAL
> > > > > at the startup right?
> > > >
> > > > That depends on what you want. If it is just GPIO then look at
> > > > smart-serial boards on the built-in port.
> > > > If that still isn't enough, you could add one or two 7i74 boards to
> > > > the 7i76E for a theoretical extra 3584 extra IO lines
> > > >
> > > > (smart serial has been recently expanded from 96 to 224 bits, but I
> > > > am not sure if any available boards actually add more than 48 io
> > > > pins each)
> > > >
> > > > --
> > > > 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, 1912
> > > >
> > > >
> > > > ___
> > > > Emc-users mailing list
> > > > Emc-users@lists.sourceforge.net
> > > > https://lists.sourceforge.net/lists/listinfo/emc-users
> > >
> > > ___
> > > Emc-users mailing list
> > > Emc-users@lists.sourceforge.net
> > > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> >
> > 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)
> > If we desire respect for the 

Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Leonardo Marsaglia]

Hello Andrew and Gene and sorry for the late reply. I hope you're doing
great!

I believe I'll use the 7i84 as Peter suggested to expand the I/Os. But
instead of the 7i76E I'll go with the 7i95 which can read encoders too.
With this I can replicate what I did on the mazak which is to fool the
homing sequence to use the index pulse of the motors on the final stage.

El mar, 22 jun 2021 a las 2:23, Gene Heskett ()
escribió:

> On Monday 21 June 2021 22:01:25 Leonardo Marsaglia wrote:
>
> > Thanks a lot Peter and Andy,
> >
> > I re read through the manual and found the SSERIAL port connection and
> > the recommendation of using a CAT5 cable cut in half. I missed that
> > part so I was a little confused about how to expand the I/Os. So, I'll
> > be more than ok with this board :)
> >
> Another possibility if you need lots of i/o, is the 7i90HD, which has a
> total of 72 lines. Firmware options for uo to 8 axises of steppers and
> encoders. Or I believe pwm-gens and encoders. The disadvantages are its
> 3, 50 pin i/o's that are all tied to the fpga, and easily damaged by
> noise. The fix for that is a trio of 7i42TA's which are effectly used as
> breakout boards, tradeing some bandwidth for the usual surge protection
> and giving you nice screw terminals to wire it up with. It can be driven
> from an epp parport, or from an spi port from a pi. With all the
> gingerbread I've put on the sheldon, I probably have 35 i/o lines unused
> yet. And I can fire up firefox and browse the net at the same time its
> running the sheldon. I felt keeping the ethernet port out of the lcnc
> arena, so the net port was available for updating and such was more
> important, and still do. 2 of my 4 machines are building and installig
> their own versions of linuxcnc from github master-gtk3 as I type this,
> including that rpi4.
>
> > El lun, 21 jun 2021 a las 4:45, andy pugh ()
> escribió:
> > > On Mon, 21 Jun 2021 at 03:27, Leonardo Marsaglia
> > > 
> > >
> > > wrote:
> > > > Is the 7i75
> > > > breakout board the way to add more I/Os to the 7i76E? And in that
> > > > case I suppose the direction of the I/O pins in determined in HAL
> > > > at the startup right?
> > >
> > > That depends on what you want. If it is just GPIO then look at
> > > smart-serial boards on the built-in port.
> > > If that still isn't enough, you could add one or two 7i74 boards to
> > > the 7i76E for a theoretical extra 3584 extra IO lines
> > >
> > > (smart serial has been recently expanded from 96 to 224 bits, but I
> > > am not sure if any available boards actually add more than 48 io
> > > pins each)
> > >
> > > --
> > > 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, 1912
> > >
> > >
> > > ___
> > > Emc-users mailing list
> > > Emc-users@lists.sourceforge.net
> > > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
>
> 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)
> If we desire respect for the law, we must first make the law respectable.
>  - Louis D. Brandeis
> Genes Web page 
>
>
> ___
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> https://lists.sourceforge.net/lists/listinfo/emc-users
>

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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Gene Heskett]

On Monday 21 June 2021 22:01:25 Leonardo Marsaglia wrote:

> Thanks a lot Peter and Andy,
>
> I re read through the manual and found the SSERIAL port connection and
> the recommendation of using a CAT5 cable cut in half. I missed that
> part so I was a little confused about how to expand the I/Os. So, I'll
> be more than ok with this board :)
>
Another possibility if you need lots of i/o, is the 7i90HD, which has a 
total of 72 lines. Firmware options for uo to 8 axises of steppers and 
encoders. Or I believe pwm-gens and encoders. The disadvantages are its 
3, 50 pin i/o's that are all tied to the fpga, and easily damaged by 
noise. The fix for that is a trio of 7i42TA's which are effectly used as 
breakout boards, tradeing some bandwidth for the usual surge protection 
and giving you nice screw terminals to wire it up with. It can be driven 
from an epp parport, or from an spi port from a pi. With all the 
gingerbread I've put on the sheldon, I probably have 35 i/o lines unused 
yet. And I can fire up firefox and browse the net at the same time its 
running the sheldon. I felt keeping the ethernet port out of the lcnc 
arena, so the net port was available for updating and such was more 
important, and still do. 2 of my 4 machines are building and installig 
their own versions of linuxcnc from github master-gtk3 as I type this, 
including that rpi4.

> El lun, 21 jun 2021 a las 4:45, andy pugh () 
escribió:
> > On Mon, 21 Jun 2021 at 03:27, Leonardo Marsaglia
> > 
> >
> > wrote:
> > > Is the 7i75
> > > breakout board the way to add more I/Os to the 7i76E? And in that
> > > case I suppose the direction of the I/O pins in determined in HAL
> > > at the startup right?
> >
> > That depends on what you want. If it is just GPIO then look at
> > smart-serial boards on the built-in port.
> > If that still isn't enough, you could add one or two 7i74 boards to
> > the 7i76E for a theoretical extra 3584 extra IO lines
> >
> > (smart serial has been recently expanded from 96 to 224 bits, but I
> > am not sure if any available boards actually add more than 48 io
> > pins each)
> >
> > --
> > 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, 1912
> >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
>
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users


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)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page 


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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[andrew beck]

I second the recommendation to use a 7i84. I use one on all my machines.
For extra io.  They are awesome

On Tue, Jun 22, 2021, 2:04 PM Leonardo Marsaglia 
wrote:

> Thanks a lot Peter and Andy,
>
> I re read through the manual and found the SSERIAL port connection and the
> recommendation of using a CAT5 cable cut in half. I missed that part so I
> was a little confused about how to expand the I/Os. So, I'll be more than
> ok with this board :)
>
> El lun, 21 jun 2021 a las 4:45, andy pugh () escribió:
>
> > On Mon, 21 Jun 2021 at 03:27, Leonardo Marsaglia 
> > wrote:
> >
> > > Is the 7i75
> > > breakout board the way to add more I/Os to the 7i76E? And in that case
> I
> > > suppose the direction of the I/O pins in determined in HAL at the
> startup
> > > right?
> >
> > That depends on what you want. If it is just GPIO then look at
> > smart-serial boards on the built-in port.
> > If that still isn't enough, you could add one or two 7i74 boards to
> > the 7i76E for a theoretical extra 3584 extra IO lines
> >
> > (smart serial has been recently expanded from 96 to 224 bits, but I am
> > not sure if any available boards actually add more than 48 io pins
> > each)
> >
> > --
> > 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, 1912
> >
> >
> > ___
> > Emc-users mailing list
> > Emc-users@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/emc-users
> >
>
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>

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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Leonardo Marsaglia]

Thanks a lot Peter and Andy,

I re read through the manual and found the SSERIAL port connection and the
recommendation of using a CAT5 cable cut in half. I missed that part so I
was a little confused about how to expand the I/Os. So, I'll be more than
ok with this board :)

El lun, 21 jun 2021 a las 4:45, andy pugh () escribió:

> On Mon, 21 Jun 2021 at 03:27, Leonardo Marsaglia 
> wrote:
>
> > Is the 7i75
> > breakout board the way to add more I/Os to the 7i76E? And in that case I
> > suppose the direction of the I/O pins in determined in HAL at the startup
> > right?
>
> That depends on what you want. If it is just GPIO then look at
> smart-serial boards on the built-in port.
> If that still isn't enough, you could add one or two 7i74 boards to
> the 7i76E for a theoretical extra 3584 extra IO lines
>
> (smart serial has been recently expanded from 96 to 224 bits, but I am
> not sure if any available boards actually add more than 48 io pins
> each)
>
> --
> 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, 1912
>
>
> ___
> Emc-users mailing list
> Emc-users@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-users
>

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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[andy pugh]

On Mon, 21 Jun 2021 at 03:27, Leonardo Marsaglia  wrote:

> Is the 7i75
> breakout board the way to add more I/Os to the 7i76E? And in that case I
> suppose the direction of the I/O pins in determined in HAL at the startup
> right?

That depends on what you want. If it is just GPIO then look at
smart-serial boards on the built-in port.
If that still isn't enough, you could add one or two 7i74 boards to
the 7i76E for a theoretical extra 3584 extra IO lines

(smart serial has been recently expanded from 96 to 224 bits, but I am
not sure if any available boards actually add more than 48 io pins
each)

-- 
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, 1912


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Re: [Emc-users] About the 7i76E and possible DB25 expansion cards

[Peter C. Wallace]

On Sun, 20 Jun 2021, Leonardo Marsaglia wrote:


Date: Sun, 20 Jun 2021 23:24:05 -0300
From: Leonardo Marsaglia 
Reply-To: "Enhanced Machine Controller (EMC)"

To: "Enhanced Machine Controller (EMC)" 
Subject: [Emc-users] About the 7i76E and possible DB25 expansion cards

Hello to all,

I'm deciding which hardware I'm about to use with the CNC router. I'm
mostly inclined to the 7i76E because it has all that I need to drive the
router in one compact board.

I think this board covers anything I'm thinking of at the moment but just
in case I need I/O expansion in the future I would like to ask: Is the 7i75
breakout board the way to add more I/Os to the 7i76E? And in that case I
suppose the direction of the I/O pins in determined in HAL at the startup
right?


You could use a 7I75 to add more protected TTL level I/O. You can also
use 1 or 2 standard parallel port type breakouts for more I/O. There are also
daughtercards for specific I/O like additional encoders or step/dir outputs.
Another option would be using the serial expansion port. One 7I84 added to the 
7I76E's serial expansion port doubles the amount of 12/24V I/O by adding an 
additional 32 inputs and 16 outputs.





Just curious about this because I'm always using new hardware on every
machine :).

Thanks as always for your help!

Leonardo

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Peter Wallace
Mesa Electronics



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[Emc-users] About the 7i76E and possible DB25 expansion cards

[Leonardo Marsaglia]

Hello to all,

I'm deciding which hardware I'm about to use with the CNC router. I'm
mostly inclined to the 7i76E because it has all that I need to drive the
router in one compact board.

I think this board covers anything I'm thinking of at the moment but just
in case I need I/O expansion in the future I would like to ask: Is the 7i75
breakout board the way to add more I/Os to the 7i76E? And in that case I
suppose the direction of the I/O pins in determined in HAL at the startup
right?

Just curious about this because I'm always using new hardware on every
machine :).

Thanks as always for your help!

Leonardo

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