In the mach 3 software there is a setting that can be check to allow either a high or low to trigger you motor. In Mach 3 Config/Ports&Pins/MotorOutputs/StepLowA will enable the motor with a low Voltage.

Adjust the motor outputs to there corresponding step pin/direction pin(if setup is following our diagram):
Step Dirt
x 2 3
y 4 5
z 6 7

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I'm connecting my PCI-e parallel expansion card to my 5 axis parallel port breakout board. However, the 3.3 volts coming out is not triggering servo step. I can measure hi/lo coming out of the parallel port when using Mach 3. Is the low voltage likely the issue or should I look elsewhere?

Sure, the USB interface has a place for 4 axes of limit switches.

Each axis can have two limit switches: one for the ++ (positive) end and one for the -- (negative) end. The positive end would be the limit switch at the end of the machine that, say the machine has a 4'x8' area, reaches a bit after the 8 foot mark. The negative end would be the limit switch behind the 0 foot location behind the origin. If the origin is in the middle, the negative would be at a little more than the -4 foot end and the positive would be at a bit more than the +4 foot end. Note that you can have more than one switch on each pin where the NC is connected in serial fashion and the NO is connected in parallel fashion (this can be seen on the diagram in the multiple limits switch section). The software configurations for the limits switches are under File -> Settings -> Limit.

A typical limit switch has three connections on it. These connections consist of COM (common), NC (normally closed) and NO (normally open). The COM would generally go to GND and the NC or the NO would go to the pin. If the NC is used, then the the switch is constantly connected until the switch is pushed (engaged) then the connection from the pin to gnd is broken (open). Use the settings in software to set whether in NC or NO configuration.

Let me know if this information was helpful (or not) by adding information to this question. Thanks.

User response:
Thank you very much for this helpful information. I'm still a little fuzzy on how the 6 limit switches physically connect to each other and to the USB breakout board. You've stated one switch (home) goes to positive and another switch (limit) goes to negative. Are all the GND prongs from all 6 switches connected to each other and going to GND on the breakout board, or no? And the NC prongs, how exactly are they connected to each other? And to the board? There has to be a diagram somewhere shows this visually, no? I don't know how to wire the switches in series or in parallel. I have already physically installed all the switches on the machine and ran the wires to where the board is. Now I just need to know where to plug these wires into the board. Also, taking into consideration that I'm using the Planet CNC software, the only settings I have pertaining to limit switches is "Enable/Disable" for each axis, and the actual limit for each axis. Nothing about NC or NO. Is that only in Mach3?
Thank you.

buildyourcnc response:
On the USB interface, the COM on the switch connects to GND and the NC or NO connects to the input pin (i.e. x++, y--, etc.)

Limit switch configuration is rather difficult to understand, especially with series and parallel. You can think of series as a single wire going from GND to the axis letter input terminal (i.e. X++ or X--). If the wire is broken, then the circuit is open (or the switch is engaged in a normally closed scenario). Normally closed is like an actual wire, and when engaged, the switch "opens" (breaks the wire). This is why we recommend in some systems that you can put many switches in series on a single pin. When one of the switches is engaged (breaking the connection) then the entire circuit of switches is broken and the machine stops.

In a parallel scenario, the state of the circuit is always broken until the one of the switches is engaged and the circuit is then closed or connected. The topology looks like a ladder. All the switches connect to both sides of the ladder and the switches are like the runs of the ladder (the horizontal bars that the feet are placed while climbing). Imagine all of the switches broken in this scenario (normally open). It would be like the ladder could be split in two, but if one of the ladder runs (switches) is closed by engaging it, then that run would connect both sides of the ladder and the two sides of the ladder would have a connection.

There is a diagram on the USB page of the various limit switch configurations. If you need more information (visual and/or otherwise), please let us know and we will immediately add that information to benefit everyone.

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I purchased limit switches from you mounted them on my machine and wire them to the breakout for using pin 12 and the ground on the breakout board, after a few minutes I got a message about a limit switch trip. Am I supposed to use the extra outport on the board instead of the ground?

For safety's sake I would recommend a new board because they are inexpensive compared to the electronics that they support. Alternatively, it's possible that the one dead pin is a simple fix, such as a bad connection or solder joint; if you feel comfortable making those repairs then it could be worthwhile to check. Finally, if you are not using all the input pins, you could continue to operate the limit switch on pin 11 and hope for the best.

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I have a breakout board and it appears that the pin 12 connection has failed: when i move my limit switches to pin 11 they work; they don't work on pin 12. Do i need a new breakout board?

Does your plasma cutter have an external trigger that voltage can be applied to make the trigger engage? If I known, please provide the brand and model of your plasma cutter so we can determine this.

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I converted my blackToe to do plasma cutting. Used the Motor control relay on the break out board and just wired it into the plasma cutter trigger. Put a large pan (like a car oil drip pan) with about 1/4 inch of water on the table and attached fixtures. 400 15ga parts later it's still working great.

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That is so cool!!

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I would like to post a story on your setup and conversion. Do you have pictures of the process and/or the new setup?

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Hello I bought a full setup of parts a couple years ago to make a cnc router and now I have decided that I want to make a cnc router/plasma. I was wondering how to go about hooking up the plasma to the breakout board

It's Mach3 USB Interface Board, I forgot to mention that!

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I'm having an issue with the AVI PWM output on my board the PW low is about half the voltage of PW High, so if I use 5v I get 2.5 v on low or if I use 10v I get 5v on low? I traced the signal back with my Oscilloscope and found that I get a PW low of 0v on the base of what looks like a smd transistor opposite the DCM connector, do you think I have a got a faulty board?

If your computer does not have a parallel port, all you will need is a low cost PCI parallel adapter card (these can be found on amazon for $15-$20). If you plan on using a laptop (not recommended) you can try to find a PCMCIA parallel adapter, but many people have frequent issues with this setup. A more expensive solution would be to purchase a USB smooth stepper board. Unfortunately, we do not supply any of these adapters and cannot attest to their reliability.

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ur gay

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I have a parallel. breakout board. and no parallel port at the back of my computer do those parallel. cards. work with the breakout board?

(These steps are to be taken with precaution, due to the fact that we do not know the model or manufacturers specifications for your BoB)

Here is a link to our CNC electronic videos(

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I have a CNC Machine from China, and the Breakout Board is not Labeled. Is there any way to test the board using Mach3 to find out the pin designations? db25 bob

For the USB controller and reversing the rotation for a motor, you would need to do this in the software (planet-cnc). In the configuration, you will need to reverse the direction by inverting the direction output.

Technically, the motor changes direction when the direction signal changes from a high to a low, or vice verse. For instance, the motor turns in one direction when the direction signal is, say, low. The motor will turn in the other direction when the direction signal is high. High is 5v and low is 0v or gnd.

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I have wired the step motors with the USB breakout board. When I jog the y axis it travels in the wrong direction. How do i switch the motors rotation?

The use of the hex inverter in the application to invert a direction signal to have a motor run in the reverse directions is relatively simple.

First, go to this link and look at the chip diagram:
https://www.buildyourcnc.com/item/electronicsAndMotors-hex-inverter-breakout-newbiehack-integrated_circuits-hex-inverter

Connect 5V from the USB interface tothe VCC pin. The pin on the keyboard jog header can be used. Connect the GND pin from the USB interface to the GND pin on the hex inverter. Connect the CW terminal from the USB interface to the 1A pin on the hex inverter. Connect the 1Y pin from the hex inverter to the driver.

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I got a question??? I am a dummy when it comes to cnc. I got 6040 1500kw water cold engraver 3 axis from china. I can not get anything out of them pertaining help they keep telling me the same thing over and over and over and I'm doing it and send them pictures that I know. Anyway email me a wiring diagram for the PRT 1500 watt spindle motor control box and has the emergency stop on and off switch manual PC and of course yhe screanm fultonsbusiness@gmail.com

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I got a question??? I am a dummy when it comes to cnc. I got 6040 1500kw water cold engraver 3 axis from china. I can not get anything out of them pertaining help they keep telling me the same thing over and over and over and I'm doing it and send them pictures that I know. Anyway email me a wiring diagram for the PRT 1500 watt spindle motor control box and has the emergency stop on and off switch manual PC and of course yhe screanm fultonsbusiness@gmail.com

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Is there a wiring diagram for hooking up your hex inverter between your USB breakout board and the controller?

To connect the parallel port breakout board to the LEDs, use step number 18. The connections are listed at the bottom. Here it is for your convenience.

For the LED connections on the parallel breakout board:

- The x axis LED will be connected to pin #2 and 5V
- The y axis LED will be connected to pin #4 and 5V
- The laser on/off LED is connected to pin #6 and 5V

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I can't find any information in the BlackTooth instructions about how to connect the 8 wires from the LED display to the parallel breakout board. The two going to the pot seem, in the illustration, to be soldered together and to the centre terminal of the pot? Help, please.

The 5V power required for the breakout board can be a simple USB male to male cable, that will connect from your computer to the board itself.
Now adding a external power supply make sure that it does not exceed a total of 5V and the standard 500 MilliAMP - 1 A.

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I have a YDH-18-5 Power Supply AC Input:100-240v 47-63Hz, Ouput: 5v - 2A and need to know if its safe to use with the Parallel Breakout Board.

The USB port on the Parallel Interface board is necessary to supply 5V power. Connect with a USB cable to a USB source.

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I purchased a parallel port breakout board. I have checked all the info and found nothing on the usb port. What is it used for?

I would need to see the drivers and what type of input it requires.

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actually my neighbour is using panasonic liqi series servo motors, and yes i can show you the connections he made on the driver terminals. he had used a loacal made breakout board, which i dont want to use... the breakout board has 5 terminals, step,direction,vcc,ground,and 12v

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The connections are the same as stepping motor drivers. I would assume that those servo motors have the closed loop control between the motor and driver and the computer is not considered as a part of the closed loop. In that case, the breakout board would work fine.

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i've seen your videos related to the connections of the breakout board to the motor driver,your breakout board dont have 12v terminal as in that local made breakout board.can i provide that extra 12v from another source to the servo motor driver?
i can send you the photos of the driver connections and the breakout board connections?
how can i purchase your breakout board,can you send your parallel port breakout board to my country?
how much would it cost me including shipping?

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What terminals will require the 12v power. If the 12v serves as the data signal level power for step and direction, then it is not possible with this board, but if the 12v serves as power for another part of the driver, then you can use a separate supply.

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i want to use servo motors(panasonic liqi series) instead of stepper motor,would it work with your breakout board if i buy one from you?

The parallel breakout board has the db25 connector for data and the USB connector for power. Connect the USB from the computer to the parallel breakout board so the breakout board will have 5V of power coming from the computer. The db25 connector (connector with the 25 pins) receive data signals for each pin from 1 to 17 and have respective numbered screw terminals, some for input and some for output (18 to 25 are gnd pins).

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Should I connect both the USB and the 25 pin connector of the parallel breakout board to the computer?

If you have received a part that does not work as advertised, or does not function properly, we will ship you a replacement. Please contact customerservice@buildyourcnc.com to make these arrangements.

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I would like to re-order another breakout board, but I would like each output tested beofore shipping. I have recieved a breakout board where the mist coolant doesnt work, and the y-axis sends a 1.5vdc signal voltage. They should all be 5v as you know, or the driver will not read.

Most motherboard do contain parallel ports, but the port connector may not be at the back (in the section where external connectors will be connected). Instead, the motherboard may contain an LPT ribbon connector on the actual face of the motherboard (usually along one of the edges). You will need a ribbon connector to a DB25 female connector.

If your motherboard does not contain an LPT header on the motherboard, you can purchase a parallel printer adapter that plugs into one of the PCI slots. The price of the adapter is very inexpensive and sometimes is actually less costly than the actual ribbon connector.

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As I am building my 20" x 24" laser engraver cutter, I notice that there is no parallel port on the onboard computer and I have the parallel breakout board any answers?

We generally use the USB to power the interface (breakout board). The current from the computer is sufficient to supply the breakout board.

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Hi, i have a breakout board that requires 5vdc and i need a power supply for this. What amp rating power supply do i need to power the breakout board without frying it?

Connecting drivers from a controller to the driver does not require relays. A controller typically has pins or terminals for Step and Direction. These terminals connect to the driver's Pulse and Direction terminals. For instance for the X axis: if you are connecting from the Mach3 USB controller, you would connect the XD (X axis Direction) terminal to the Driver's DIR+ terminal, and the XP (X axis Pulse) to theDriver's PUL+ terminal, and the GND from the controller to the PUL- and DIR- terminals.

I have thorough step by step instruction for two controllers:
https://buildyourcnc.com/item/electronicsAndMotors-electronic-component-breakout-Mach3-USB-Board
https://buildyourcnc.com/item/electronicsAndMotors-electronic-component-breakout-Mach4-mach3-USB-ethernet-Board

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When you are talking about relatys, that is all Greek to me. Will a breakout board do what I need to hook up to my drivers?

The parallel (printer cable) port is uses the computer as its main source of pulse trains to operate the motor driver directly. Parallel ports are a direct connection from the processor commonly referred to as GPIO pins (General Purpose I/O pins) and provides a convenient and powerful way to interface with the computer. The parallel breakout board is included in those kits only to condition those signals for use with the drivers.

The USB serves at the actual controller, sending the pulse trains, but the computer sends simple human readable instructions to the USB controller to tell the controller how to send pulses.

The non-technical differences that may serve as the most important information to you is that the parallel configurations allow for a wider variety of industry standard software that can be used to control the cnc machine. The USB that we offer requires the operator to use a software called Planet-CNC software which is a very well made and feature full cnc control software.

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USB Motion controller breakout board work with planet cnc software?

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WHAT'S THE DIFFERENCE BETWEEN PARALLEL BREAKOUT BOARD AND USB ITERFACE?