LinuxCNC 2.8 DM542T drivers Mesa 7i96 controller

I am trying to configure my control box. I have a SFF computer running Mint 19.2 with the RT kernel that will be in the control box with everything else I am sure this will be the beginning of many questions as I am new to CNC as well as to Linux.

I have tried looking online for a good wiring diagram for the parts that I have. I have come close but everyone use a little something different.

First question: The Mesa 7i96 needs a 5V supply. Can I use a USB port on the computer to provide that? If not, I have unused drive slots that have a 5V and 12V connectors, can I tap into one of those? I did not see what the amp draw is on the Mesa card nor on the DM542T drivers. What is the possibility of malfunctions with the system if I use the computer power?

Second question: Some of the videos that I have watched with the stepper drivers jumper the PUL +5V and the DIR +5V terminals together while others do that but add a 5V power source to one side. Do I need to supply 5V to the driver if I have already wired the 36V power to it? Or is this supplying power back to the 7i96?

Third: The DIP switches came set from stepperonline. It looks like it is set for 1.0 peak and .71 amp RMS, 1/2 current and 8 micro step and 1800 steps/rev (for 1.8 degree motor). I bought the drivers and the motors as a set from stepperonline, How do i figure what those settings should be? I am assuming that they set it for the motors that I received.

I have included a picture of the grid with everything mounted to it. I will build the box around the grid so I can add a fan and filter to keep everything clean. I hope to have the box finished this week so I can connect the motors and begin programming the interface to LinuxCNC. I appreciate this community and all of the feedback and advice it provides. If this is too much hardware related and not enough LinuxCNC related and needs to deleted I understand.

The Mesa 7i96 needs a 5V supply. Can I use a USB port on the computer to provide that
NO USE a REAL Powersupply 1A min you may need some more power 5V in system so USE a 2-5A in case
you can use a Stepdown 3A from your 36V DRIVER supply

the PUL and DIR signals go BOTH to the 7i96 + and minus NO 5V to that
if you wish to connect 5V to ENA+ DIR+ PUL + only connect the minus to the 7i96
only the ena + is at 5V as you wish to TURN on off the Stepper for manuel Movement
otherwise keep the ENA + and - Unconnected

Here is what I understand (These are the labels on the 542 and the 7i96 respectively):

PUL + (5V)

---

STEP0+
PUL - (PUL)

---

STEP0-
DIR + (5v)

---

DIR0+
DIR - (DIR)

---

DIR0-

I then have a GND and a +5VP left on the 7i96. I assume that the +5VP is supplying +5V to the field, which is only 3.6V. I don't think I need to connect that anywhere at this time. I am planning on using the grid or a separate bus to ground everything to, which will be tied in to the 110V ground. Is this a good idea or do I need to have a separate ground for the DC systems?

Sorry, I tried to draw dashed lines to connect the terminals. I should have used <-->. Hopefully it makes sense without them.

Thanks for the help. I got a separate 5V power supply. Everything lights up green and no magic smoke escaped!

Now I am trying to configure the 7i96 to ruin the motors. I am using pncconf since it had the 7i96 template. Where do I find the info to put in it? I have never programmed something like this before and to be honest, my eyes start cruising when I read through some of the instructions. Any help to point me in the right direction would be appreciated.

I'll try and answer this for the third time.....The Beagle is trying to help.

I use a 7i92/776 combo and this is my wiring setup.

Stepper Drv________Driver (7i76)
PUL+ _____________STEPx+
PUL- _____________ STEPx-

DIR+ _____________ DIRx+
DIR- _____________ DIRx-

Bootlace ferrules make wiring so much more easier and neater, not a requirement but it makes life easier when you need to disconnect and reconnect terminals.

With regrads to grounds:
All my PSU DC Neg terminals are not connected to each other
All my PSU AC Grounds are connected to a single nut & bolt connected to the chassis aka STAR Configuration (nothing to do with 3 phase motors). As this is what the regs in my area say.

The only AC mains wiring advice you get off the internet that should be followed is to check your local regs and check with a local Electrician if you aren't 110% sure.

Stepper settings should be available on the data sheet for your stepper motor. If you have no luck ask your supplier, don't assume that the driver is setup correctly.
If you look at the data sheet for your stepper driver it has some good info regarding wiring.
www.omc-stepperonline.com/download/DM542T.pdf
Unfortunately it's a bit spares on the timing values.
Here are some conservative values that might help.
DIRSETUP = 20000
DIRHOLD = 20000
STEPLEN = 5000
STEPSPACE = 5000

Oh and finally with 8 micro stepps you will have 1600 steps/rev ie: (360/1.8)*8 = 1600........I wasn't sure whether 1800 was a typo or not.

Thank you. I have not had time to work on it this week but hopefully I will get some time this weekend.

This is pretty much the exact same setup I have, i.e. DM542T + 7i96. Beagle got the right information.

Attached the cabling of my setup, note that I also connected up the enabled/disabled signal through the extra outputs on the 7i96. Those signals are inverted so you need to use a 'not' component in your hal file to invert them if you plan to do the same.

Thanks for the confirmation and the picture. My set up is similar now. I do not have anything on TB2 nor TB3 at this time. What is the purpose of connecting the Enable/ Disable? E-stop? I will have an E-stop and limit switches once I get it all working so I will need to figure that out. I can't quite tell what is connected to where in your picture. Do you have a basic diagram or something?

Also, I don't know anything about HAL, MESAFLASH or what I need to "talk" to the motors. I have one motor connected to one of the drivers to see if I can make it move but I get lost in what needs to happen next. I reloaded Mint 19.2 and the RT Kernel and LINUXCNC 2.8. What do I need to do now? PNCCONF? Install something from the mesa 7i96 zip folder that I downloaded? Any help is appreciated.

First thing I think you need to do is read the docs, I'm sorry I know this sounds passe, but........ you will better prepared to digest what is suggested and you will be in a better position to ask questions. Give yourself a bit of time to read and digest the docs, it takes some time, but running a cnc machine isn't the same as using a printer, it's not a case of design and press a button.

linuxcnc.org/docs/2.8/html/

99% of the time the enable\disable on the stepper motor drivers are left disconnected. It's not something to be really worried about.