Machine homeing Test

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Hartmut Eger

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Dec 5, 2021, 4:15:10 AM12/5/21
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Good morning open pnp community,

I struggle with my machine and just get stuck.
I have a problem with the homing of the machine.
As soon as I start my smoothie board, it remembers the current position as 0.0.
How can I deactivate this in order to test my homing with the active end stops

mark maker

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Dec 5, 2021, 5:30:17 AM12/5/21
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Hi Hartmut

Homing does not bother about the current position, i.e. it does not matter if it has to move into the "negative" from the perspective of the power-on coordinates. It will slowly move towards the homing switch you configured and when it hits the switch it will reset the coordinate to the homing coordinate you have configured for the axis. You can configure the homing direction (min/max), and the homing position (to which the coordinate is reset).

https://smoothieware.org/endstops

Or for the modern 6axis endstop syntax:

https://smoothieware.org/6axis

_Mark

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Hartmut Eger

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Dec 5, 2021, 6:24:33 AM12/5/21
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Hello Mark,

Thank you for your answer.
But unfortunately I don't know how to activate this ominous HOMING.
I've been busy with it for the last 14 days, but no matter what I've read or tested in the Wiki, Google Group or Open PNP, I just can't get anywhere.

D.Mouradov

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Dec 5, 2021, 6:47:25 AM12/5/21
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Hi you can start by testing end stops switches by using "pronterface" software  by sending  M119
FCVXOFTIGWJY4RX.jpg

Hartmut Eger

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Dec 5, 2021, 7:05:20 AM12/5/21
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Hello D.Mouradov,

my end stops for X, Y and Z are active.
I can also control this via M119.
I don't know how I can turn the hominh on on my Open PnP machine.
As soon as I switch on my machine (with Smoothie Board) I get the coordinates of my axes
X = 0
Y = 0
Z = 0
These values refer to the current positions of my 3 axes.
As soon as I want to move my X axis into the homing position via G code G28 X, nothing happens because the X axis is at zero.
So now I don't know how to move my axes into the homing position.05-12-_2021_12-56-55.jpg

D.Mouradov

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Dec 5, 2021, 8:10:43 AM12/5/21
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1. When you push limit switches in pronterface you can see it?
2. attach here smoothie config i will compare it with mine

Hartmut Eger

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Dec 5, 2021, 8:19:35 AM12/5/21
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to 1. yes all end stops switch correctly to display this correctly in Pronterface. In the picture, the X Enstop has been triggered
config

Hartmut Eger

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Dec 5, 2021, 8:20:38 AM12/5/21
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05-12-_2021_14-18-05.jpg

D.Mouradov

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Dec 5, 2021, 8:45:16 AM12/5/21
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I do not see anything abnormal in the config. 
as I understand, even with the help of Pronterface you can not home or jog your machine? if yes then this is very strange.  Did you check the motor connections? I just have no more ideas.

Hartmut Eger

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Dec 5, 2021, 8:57:47 AM12/5/21
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my motors are all working correctly.

I only have the problem with setting the homing.
the jog works in the Pronterface as well as in the Open PnP software all axes move in the right direction and at the right distance.

Since my machine defines the current position of the X, Y, and Z axes as 0 after the start.
With the GCode command G28, my axes are only shifted to the position that the axes had after switching on.
I cannot make a reference run to the limit switch.
And I just don't know how to change this anymore.

mark maker

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Dec 5, 2021, 9:06:53 AM12/5/21
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One thing to check is polarity of the switches. It is best to wire the switches in NC i.e. "normally closed" configuration, i.e. they are conducting current, until pressed, usually pulling down an input pullup resistor. So in case your wires break, it is treated as if the switch was pressed, for safety.

I frankly not longer remember how it all is configured on Smoothie, but it's a thing to check.

Also I'm not sure Smoothie support the G28 X command without a coordinate. Try G28 without any axis letters, or try G28 X0 or whatever homing coordinate you want.

_Mark

Hartmut Eger

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Dec 5, 2021, 9:59:51 AM12/5/21
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The limit switches are wired to NC.
These also work as they should. M119 0 is not triggered.
Triggered is reported back with M119 1.
G28, G28 X, G28 X0, G28 Y, G28 Y0 all bring the same result, the X and Y axes are moved to the same position but not at all to the limit switches.

mark maker

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Dec 5, 2021, 10:21:13 AM12/5/21
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> the X and Y axes are moved to the same position but not at all to the limit switches.

what exactly do you mean?

If they do not move far enough, check the max_travel settings.

_Mark

bert shivaan

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Dec 5, 2021, 10:34:17 AM12/5/21
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It sounds like the correct homing command is not being sent, or his controller thinks it is already homed?

My understanding is when he sends G28 (with or without axis info) his control does not start to home as if it thinks it already is home.

Hartmut Eger

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Dec 5, 2021, 11:01:14 AM12/5/21
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When I strate my machine, all 3 axes X, Y and Z are set to 0.00 regardless of the position of the axes.
if I now move the axes e.g. X +100 Y + 250 Z-10 now I send via GCode G28 so the axes X and Y are back to the position X = 0.00 Y = 0.00 and Z remains in position -10 .
But this is not the position of my limit switches that are mounted on Xmin and Ymin.
this is my problem, I just don't know how to say my smoothie boerd and smoothie goods to get a proper homing.

mark maker

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Dec 5, 2021, 2:18:29 PM12/5/21
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Sorry, I still don't understand. Auf Deutsch vielleicht?

Hartmut Eger

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Dec 6, 2021, 2:47:57 AM12/6/21
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Guten Morgen Mark,

wenn ich meine Open PnP Maschine starte, werden alle 3 Achsen X, Y und Z unabhängig von der Position der Achsen auf 0,00 gesetzt.
Jetzt werden die Achsen z.B. X +100 / Y + 250 / Z -10 verfahren.
Nun sende ich per GCode G28 (egal mit oder ohne Achs,- oder Koordinatanangabe) damit werden die Achsen X und Y wieder auf die Position X = 0.00 Y = 0.00 und zwar die Werte nach dem Start der Maschine verfahren und Z bleibt auf Position -10 stehen.
Dies ist jedoch nicht die Position meiner Endschalter, die auf Xmin und Ymin montiert sind. Das ist mein Problem, ich weiß einfach nicht, wie ich meinem Smoothie-Board und der Smootiehwaren sagen soll, um ein richtiges Homing zu bekommen.

Vielen Dank für Deine Unterstützung

Gruß
Hartmut

mark maker

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Dec 6, 2021, 3:13:41 AM12/6/21
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Hello Hartmut

OK, after having received your PM in German, I think I understand what happens. I answer here in the group, so others with the same problem can find the solution later.

Which firmware do you use? Mine?
https://github.com/openpnp/openpnp/wiki/Motion-Controller-Firmwares#smoothieware
You need my extensions if you want to use OpenPnP in a modern way.

I think you flashed a firmware that was compiled in GRBL_MODE. The command is then not G28 but $H.

https://smoothieware.org/grbl-mode

G28 changes its meaning and moves the machine back to the homing location instead. So exactly what you are observing.

Note: I do recommend you use the firmware from my blog, which is compiled without GRBL_MODE, as it is the standard OpenPnP convention. But if you insist you can recompile the sources with GRBL_MODE, arguably it is more "CNC standard". OpenPnP Issues & Solutions will automatically detect this and use $H as the homing command.

In any case, be sure to use Issues & Solutions to setup OpenPnP:

https://github.com/openpnp/openpnp/wiki/Issues-and-Solutions

_Mark

Hartmut Eger

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Dec 6, 2021, 4:23:31 AM12/6/21
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Hello Mark,

This version is currently installed on my Smoothieboard

I have to check whether I am working with GRBL_MODE.

Thank you for pointing out the firmware, I will install the version from your side and keep working. But will not come back until December 10th. to

yes I use this page Issues & Solutions to setup OpenPnP for my configuration

Gruß
Hartmut

mark maker

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Dec 6, 2021, 2:04:00 PM12/6/21
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> I have to check whether I am working with GRBL_MODE.

Yes you are, the -cnc suffix tells me that.

_Mark

Hartmut Eger

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Dec 6, 2021, 2:43:02 PM12/6/21
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Yes it is the suffix CNC

firmware-cnc.bin

Latest commit 107403b on 28 Aug 2020

Those who can read have a clear advantage I haven't read the readme file.

NOTE

Make sure you download the binary file and not the HTML page.

Click the file you want, then click the View Raw button to get the raw binary file.

Flashing the HTML will mean the leds will not flash :)

the firmware-cnc.bin is a build for CNC. It has a different layout for the optional LCD more suited to CNC, this layout requires a graphic LCD. This build also excludes modules required for 3D printing like temperature control and extruders etc. It has only 3-axis compiled in. It also uses $H to home as G28 is used to park in real GCode.

The regular firmware.bin builds are for 3D printers and exclude CNC moudules such as spindle and drilling cycles. It has 5-axis built in so you can use two extuders out of the box.

Sorry Mark that was my mistake


Hartmut Eger

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Dec 7, 2021, 1:56:39 PM12/7/21
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Hello Mark,

can you please confirm that this firmware version from your blog page is the right one for me?

For current OpenPnP 2.0 versions: Download the newest 5-axis firmware.bin and don’t forget to let Issues & Solutions do the Switch Linear ↔ Rotational as explained above. Made with:
make AXIS = 5 PAXIS = 5

My PnP machine has an X-axis, a Y-axis and a Z-axis as well as the two nozzles C1 and C2

Hartmut Eger

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Dec 7, 2021, 1:58:45 PM12/7/21
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Open PnP Maschin Date 20211125.jpg

mark maker

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Dec 7, 2021, 2:09:09 PM12/7/21
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