New Machine Build- EMC2 E-stop parallel port pinout and E-stop loop

[GreenLead]

I've read up about this in the EMC2 wiki already but it appears to be somewhat vague for a beginner like me.

Basically what I'm trying to do is to implement an Emergency stop (E-stop) setup. The spindle is probably going to be running on 24V.

I've looked at the user manual and it says that by default Pin 1 of the parallel port is ESTOP OUT, in the outputs section (PC to Mill). I find this strange; isn't pushing a E-stop switch an input as opposed to an output as the manual suggests?

I also read up about something along the lines of an E-stop loop, where all the relays wired to auxiliary devices (spindle, coolant pumps etc) are in series.

Any suggestions and simple working circuit designs would be greatly appreciated. Thanks in advance!

[Gads]

HI GREENLEAD I HOPE THIS HELPS, I NEVER RAN E-STOP WHEN I USED MACH3
BUT DECIDED TO WIRE IT INTO MY BOARD BEFORE STARTING TO PLAY WITH EMC2. IT SOUNDS LIKE YOU ARE IN STEPCONFIG SCREEN ALREADY. ON MY SETUP PIN 10 IS E-STOP IN. PIN 1 ON MY BOARD IS AN OUTPUT CONTROL
SUCH AS COOLANT ETC.. I CAN'T REMEMBER OF THE TOP OF MY HEAD BUT I MAY HAVE PIN TEN SELECTED AS INVERTED. DO YOU HAVE A CONTROL BOARD AND DRIVERS ?

I DECIDED TO TRY EMC BECAUSE IT'S FREE BUT THE TRIAL VERSION OF MACH3 WAS EASY TO UNDERSTAND AND SETUP FOR ME BUT CAN'T AFORD THE $160 TO UNLOCK THE LIMITED PROGRAM LENGHT. YOU MIGHT WANT TO CONSIDER MACH3 BY ARTSOFT TO GET STARTED THEN SWITCH LATER. I HAVE GOTTEN VERY LITTLE FEEDBACK ON EMC POSTS BUT STILL TRYING TO WORK OUT ISSUES SO I CAN DECIDE ON WHICH SYSTEM I WILL STAY WITH.
THIS SOFTWARE IS VERY CONFUSING TO SETUP AND I'M IN THE MIDDLE OF TRYING TO SETUP MY LIMIT HOME SWITCHS AND ITS GOT ME PULLING MY HAIR OUT.

[Gads]

GREENLEAD I THINK I STARTED VENTING MY OWN CONFUSION RATHER THAN FULLY ANSWER YOUR QUESTION. ASSUMING YOU HAVE A BREAK OUT BOARD
BETWEEN YOUR PC AND MILL. OR MAYBE YOUR MILL HAS ITS OWN BUILT IN INTERFACE THAT YOU PLUG YOUR PAR PORT INTO. WHAT THE SOFTWARE IS DOING IS LOOKING AT THE VOLTAGE ON A GIVEN PIN TO SEE IF IT IS HIGH OR LOW AND DECIDING IF THE ESOP HAS BEEN PUSHED. THIS IS INTERNAL PC VOLTAGE MEASURED AT THE TRANSISTOR LEVEL. DONT TRY AND PUT VOLTAGE OR GROUND TO YOUR PC'S PAR PORT DIRECTLY.
WHAT YOUR BREAKOUT BOARD DOES IS ISOLATE YOUR PC FROM THE MACHINE, THE BOARD HOWEVER IT MAYBE SETUP TO DO IT TAKES YOUR ESTOP INPUT AND CHANGES THE STATE OF THE PIN FROM HIGH TO LOW OR VISE VERSA. IN MY CASE THAT IS PIN 10. AND ON MY BOB CAMPBELL BOARD I HAVE A SOCKET I WIRE A SWITH INTO VIA TWO WIRES. THE SWITCH WILL BE OPEN OR CLOSED BASED ON MY ESTOP. WHEN I SETUP I SAW WHAT YOU ARE TALKING ABOUT WITH PIN 1 . THERE MAY BE SOME SYSTEMS OR SETUPS OUT THERE THAT WOULD USE PIN 1 AND 10 AS AN ESTOP SETUP, OUT 1 AND IN 10 BUT WITH MY SYSTEM PIN 1 IS A CONTROL FOR EXTERNAL DEVICES. HOPE THIS HELPS, ANY QUESTION MESSAGE ME.

[acondit]

Originally Posted by GreenLead I've read up about this in the EMC2 wiki already but it appears to be somewhat vague for a beginner like me. Basically what I'm trying to do is to implement an Emergency stop (E-stop) setup. The spindle is probably going to be running on 24V. I've looked at the user manual and it says that by default Pin 1 of the parallel port is ESTOP OUT, in the outputs section (PC to Mill). I find this strange; isn't pushing a E-stop switch an input as opposed to an output as the manual suggests? I also read up about something along the lines of an E-stop loop, where all the relays wired to auxiliary devices (spindle, coolant pumps etc) are in series. Any suggestions and simple working circuit designs would be greatly appreciated. Thanks in advance!

GreenLead,

Here is the E-stop configuration that I am using.
net estop-ext <= parport.0.pin-10-in-not
net estop-out <= iocontrol.0.user-enable-out
net estop-ext => iocontrol.0.emc-enable-in

Alan

[GreenLead]

Thanks for the help so far everybody!

At the moment I'm actually still building my controller (Allegro 5804B unipolar stepper IC), so I hadn't got around to actually installing and configuring EMC2 yet, let alone build any axes. I was simply studying the user manual.

The controller can be found here . By itself it doesn't have any optoisolation capabilites, and I also don't have a BOB.

Gads, your explanation seemed to clear things up a wee bit. Now that I understand that you have used a switch on your BobCampbell board (and never to directly ground or pump voltage to the parallel port!), does anyone know how I can build a simple E-stop circuit that will go into Pin 1 of the parallel port?

Also, I've heard that the E-stop circuit can shut off any auxiliary devices (spindle, coolant pumps etc) in series. How would I put something like that together?

I'd like to tackle (with everyone's help) building a working E-stop pushbutton and circuit, then we can move on to configuring it in EMC2.

Again, thanks to everyone for their help so far, and apologies for sounding like a total idiot.

[Big John T]

Install EMC and use the stepconf from the menu to set up your machine. Then wire up the estop to the input you choose. Some good examples on gecko's site in their user manuals.

With version 2.2.2 EMC2 got real easy to configure...

John

[GreenLead]

Originally Posted by Big John T Install EMC and use the stepconf from the menu to set up your machine. Then wire up the estop to the input you choose. Some good examples on gecko's site in their user manuals. With version 2.2.2 EMC2 got real easy to configure...

John, I'm using the (default) pin 1 of the port for E-stop. Pin 1 hardware wise is an output. How would you force a switch input to a output pin? I'm assuming you also need an opto-coupler, as Gads pointed out how unwise it would be to directly apply an external voltage to the port.

Also, can you show me which Gecko user manual discusses E-stop in EMC2? I can't seem to find it.

[Gads]

Hello again greenlead
I understand your confusion and wish i could give you a better answer
I noticed a link to similar questions at bottom of the page when i was looking at your posts and found a similar question and no definate answer but the poster may have found an answer you might try messaging him. my thought is that this pin still should be controlled by your opto isolated controller board. and from what i read of his links etc was the switch was a normally open switch that trigered when closed. my setup is on pin 10 but i believe i have the signal set to inverted. my concern for non isolated switching is based on a project i tried before taking the plung into building a cnc controller when i tried making a digital readout using the par port and led hal sensors and basic programming, i think i fried 2 par ports trying to work out opto isolated circuits etc.. i do know you can ground the port and the pc will see the pin status change. but i do believe a resistor would be recomended to prevent to much current flow through the ports transistor. i dont have the page open but this was the posters question if you find it he has some links that might help( Parallel pin 01 - E-stop use as Input or output?) (username mike944)

gads

[GreenLead]

Hey Gads -

I think I figured something out - it turns out Pin 1 is always going to be an output, because that's the way parallel ports work. I just ran stepconfig (although not to the end), and by default it is ESTOP Out. The thing I was looking for turns out to be ESTOP In on Pin 10, as Alan had shown from his config file.

(At this point, I'm feeling rather sheepish...)

Reading up a bit more today, I think this is what is supposed to happen:

When an external N.C. EStop pushbutton is untouched, ESTOP In (Pin 10) remains low, so EMC2 keeps ESTOP Out (Pin 1) high as it is safe. Pin 1 is optoisolated to a 24V relay that goes to the spindle power supply and other external devices like coolant pumps and dust extractors before reaching ground.

When the external EStop is pushed, it breaks the circuit, and ESTOP In goes high (An optoisolated +5V source with a 4.7kohm). EMC2 then pulls ESTOP Out low, shutting off the 24V relay and in turn, the spindle and everything else.

I think the logical first step for my build would be to make an optoisolated BOB first. Does anyone have any suggestions? One issue I was thinking was that, sure, the ParPort outputs (PC to Mill) are optoisolated to prevent stepper backEMF from destroying the ParPort, but should the inputs (Mill to PC) be optoisolated as well?

[unterhaus]

The reason that you need an estop out of your computer is just in case emc figures out that there is an estop, and the rest of the machine is too busy crashing to have noticed yet. The way I intend to set up my machine is that anyone that thinks something went wrong can say estop: limit switches, estop buttons, amp faults, EMC, etc.

[Big John T]

Sounds like you have a handle on it now...

John

[tyo]

hello gentleman..
how to configure parport input..??
why when i configure by 0x379..then i input the signal (logical.1)...that's doesn't work..??