Would you be willing to share your source for the controller? I am trying to work on a cnc controller, but am having difficulty with the parallel port part. An example would really help.
-Adam
I haven't looked in for a while look's like great progress I had a thought I don't know if it would stand the load what about a large ball screw with a servo and encoder the JD need's to have the pin moved about every 45dg. or so I'v looked at there larger bender and I think the die's move in it Good Luck Kevin
Would you be willing to share your source for the controller? I am trying to work on a cnc controller, but am having difficulty with the parallel port part. An example would really help.
-Adam
www.adambrunette.com - Converting My Harbor Freight X2 And My Jet Jvm-830 Knee Mill, As well as many other projects.
He is having problems with the parallel port part too, as stated earlier.
If your goal is to create a 3 axis cnc controller from scratch, I think you would be better off going with Mach3 or a similar program. You will have a working program which would be difficult to make any improvements on in an amateur program. Spend your time running the software, not debugging it. Developing a motion controller is no small task, especially a windows based one. If you are only looking to learn, or God forbid "have fun" programming, then more power to you.
I try to do only what programming I have to. Leave that fun stuff to the software engineer types.
Matt
Matt,
I will probably take a look at Mach again. I shyed away from it because of its unreliable encoder capabilities. I am willing to bet that Mach looses count when an encoder is revolving at a high rate. My encoder will revolve 101 degrees in 15 seconds. Mach3 might be able to keep up with that, especially at 360 PPR.
I still believe I can make a program to control my bender. I am not a big fan of programming, but I would like to brush up on my VB. The project is supposed to force myself to relearn it. The project is now due in March in order to be entered into a project of the year contest at my school.
It is my hope that with Mach3 and VB scripting, I can get this mofo to work! I really would like to get the rotary encoder working soon; I am itching to make a roll cage for my Jeep.
Adam,
My controller is a 2 year old computer. If you wish to communicate with the parallel port, a file (inpout32.dll) must be placed in your /windows/system32 folder. You must address the file so VB or C++ can use the functions. I have written a program that can control the hydraulic valve by pressing a button on the keyboard. I haven't gotten past that point. Refer to earlier posts for a few links to read about the inpout32.dll file. It can be downloaded from http://logix4u.net/Legacy_Ports/Para...000/NT/XP.html
Well it's been a while. I am finally back on the project. School has been kicking my ass so I had to put the project on hold. I have to finish my project by the end of February to be considered for a Herman something or another award. I have officially switched BACK to Mach3. I have been messing around with the rotary encoder, but can't quite get it to work in Mach3.
Here is a link to my encoder:
http://web6.automationdirect.com/adc...)/TRD-SH360-VD
Here is a PDF for tech specs:
http://supahonkey.com/tube%20bender/.../encoderld.pdf
The rotary encoder is a diff encoder. I have assigned the following wires to the breakout board:
Blue (0V): Not in use, what do I do with this?
Brown: Power Supply (Connected to a 5V pin)
Black: Out A+ (Connected to input pin 12)
Purple: Out A-
White: Out B+ (Connected to input pin 13)
Gray: Out B- Orange: Out Z+ (Connected to input pin 15)
Yellow: Out Z- Shield:
GND (Connected to ground)
What does the blue wire do? It reads 4.10V when it is hooked up. Can I leave A-,B- and Z- disconnected? The Output pins (A,B,Z) all read 4V. How can I test the encoder in Mach3?
I have pins configured as follows:
Where do I go in Mach3 to verify that the MPG is working?
From the look of your connection descriptions the 0v is the 5v supply common, Ground is usually reserved for a shield ground etc.
This is where many of the products you see described here inject confusion by using the term Ground when they mean supply common.
You should be able to leave the -ABZ pins unconnected.
If you have it powered right, you can put a meter on the A or B and common and VERY slowly turn the shaft, you will see the 0 to 5v transitions.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.
Al,
Thanks for the quick reply. What do you suggest I do with the brown (power supply) wire? Should I leave it connected to the 5V pin and hook the the Blue (0V) wire up to a 5V pin also? I hate "experimenting" with wire configuration when I am unsure. I don't want to blow my encoder!
Actually if you look at the PDF, it shows Blue 0v common and brown +5v.
IOW wherever your 5v supply is coming from, as well as the 5v power, you will have a complementary common, now this is sometimes grounded and hence the confusion.
Even if the supply common IS grounded I would not use a Ground connection, but find the source of the supply and get it from there.
What/how are you to supplying the encoder, presently?
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.
I am supplying 5VDC from the computer's power supply. The 5VDC connects to the breakout board. It then disperses the 5VDC to pins on the board. I am not familiar with the term "common". What does it mean? I can grab a ground from the source, as it connects only a few pins away on the breakout board.
I would like to make sure I am doing this correctly:
Blue wire (0V) goes to a 5VDC pin on the breakout board. Ground (shielded wire) wire goes directly to the ground "incoming" source, not through the breakout board. Does the Brown (power supply) wire simply provide 5VDC for the purpose of connecting in parallel to another device?
I looked back through your posts and I see you are using CNC4PC for a break out board.
If you are feeding the encoder through this board, ground is used extensively instead of common, this is where the confusion arrises, unfortunately.
BTW, it is possible to get the 5v supply for a differential encoder directly from the parallel port and feed the AB inputs directly into the port. Bypassing any BOB.
You can also feed the AB directly to the port and pick up the 5v & common from one of the PC Power Supply Hard drive sockets.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.
I don't think my problem is correctly picking up the 5V or the ground, but rather which wire on the encoder should pick up the 5V. I am still confused as to the purpose of the blue (0V wire). Does it pick up the 5V? The 5V power and the ground are picked up from a PC hard drive socket.
I tried hooking the blue (0V wire) to the 5V on the BOB. The blue wire (power supply) shows 4.7V. I see no fluctuation in voltage on A+ or B+ when read from a multimeter. They show a constant 4.7V, no matter how slow I rotate the encoder. Any thoughts on checking rotary encoder functionality through Mach3?
When the encoder is hooked up properly, you should have +5v (brown) with respect to the blue (0).
In your case 'Ground' is synonymous with 0v (blue).
Ground is a term which should mean a conductor is at the same potential as Earth Ground.
When equipment like BOB's etc are labelled ground, they really mean power supply common or the reference point when you take voltage measurements.
This is a direct quote from the CNC4PC :
"These grounds must be common with the ground of the speed control connections but must be isolated from ground of the board"
Obviously only one of these 'Grounds' can be earth ground if at all.
IMO , the terminology is very confusing and goes against what I am used to using.
If you measure the voltage on a PC power supply connector, the black is common, the red is +5dc and the Yellow is +12vdc, when you measure them, you are using 0v (common) as a reference.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.
Al,
Thanks for your explanation, I have never thought of ground as a reference point at which voltage is measured. The encoder is actually working now. I haven't tested it in Mach3 yet, but voltage varies on A+ and B+ when read from a multimeter.
I hooked up the "ground" of the encoder to what is probably the common on the PC's power supply. I am assuming the PC hard drive 4 pin connector's ground is truly common. Under this assumption, the "ground" to the BOB is simply a common. Meaning the common on the encoder and the ground on the encoder ultimately connect to the same "common".
I am not familiar with DC, but is it safe to say that DC common is the same as AC neutral? I thought that "neutral" was only used in AC circuits, not DC. I could hook the true earth ground of the encoder to the bender frame, which grounds to a true earth ground.
Any thoughts on Mach3 displaying an encoder reading through an on-screen DRO?
I still think there is some confusion in the use of terms, but we will leave it for another day.
But AC neutral is a classic example.
Neutral in the case of single phase is the conductor we use as a (common) reference to measure the other one against.
As there is no difference between the two, we could use either conductor as a neutral.
But invariably we take one and we call it neutral and then we ground it, i.e. we connect it to earth ground, now we have a grounded neutral, which is just another way of saying we have a grounded common.
Al.
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.
Its been a while since I played around with an encoder in mach. I seem to remember something like this:
Setup input pins (think you have this under control)
Setup in general config? Not sure if there is anything you need to do here.
Hit the tab key to bring up the jogging control.
I think you have to check a box to enable the MPG.
Then you should be able to select an axis (X,Y,Z) and turn the encoder
The DRO for the selected axis should move, and your axis would move if you had it connected.
The other settings in the input pins setup can be used to change the amount each turn of the encoder moves your axis.
Matt
I am getting a fluctuation in voltage when I read either A+ or B+. I am worried that I screwed up my rotary encoder because during my wiring, I hooked the blue wire (ground) to a 5V pin on the BOB. I never hooked up the actualy brown wire (power) when I hooked up the blue wire. I don't want to keep trying to figure out why Mach isn't reading the encoder when it's actually a fried encoder. Is there a simple way to test whether an encoder is working?
Like Al said, if you hook up power to the encoder and turn it VERY slowly, you will see the A and B channels change state from 0V to 5V and back again. It should be a square wave with 50% duty cycle. You have to turn it very slowly or your multimeter will just average the high and low and read something around 2.5V. A more intuitive approach, which may teach you a bit about encoders along the way would be to find an oscilloscope at school. Put 1 channel on A and the other on B and you should see two square waves which are 90 degrees out of phase. The phase relationship is shown in your datasheet on page 3. This is what you should see on the oscilloscope.For all of this you need to have your power and common connected so the encoder is actually being powered.
Matt
Last edited by keebler303; 02-09-2009 at 10:12 AM. Reason: added some info
Unless you actually reversed the brown and blue to the 5v supply it should not have damaged the encoder, if all you did was hook up one wrong connection at a time.
You can either test it with a meter like I mentioned or the best way is an oscilloscope.
Although you may not be using them, you should see the opposite polarity on the -A to the A etc. Test with respect to the blue.
You should see a 0 to 5v transition, or close to 5v when it is turned slowly.
Al.
Oh..it looks like you got twice the advice
CNC, Mechatronics Integration and Custom Machine Design
“Logic will get you from A to B. Imagination will take you everywhere.”
Albert E.
Just finished reading thru the entire thread, looks good so far.
Keep up the good work...