Help with Delta Tau PMAC2A PC104


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I have a Delta Tau PMAC2A PC104 at 80MHz. I am trying to build my own GUI and control several motors using the controller through the serial port (RS232). But I have some very noob questions:

1. From the software I got from Delta Tau, I see that you can just send terminal commands to the controller, but does anyone know where to find these commands? or are they the same as the script form? e.g. to move one motor, just go like "X500", etc.

2. Also, from the data sheet, I found that the chip can be connected at a higher baud rate other than 38,400... but when I tried that, I couldn't establish a connection... anyone have any idea why? I am also wondering if anyone knows how many bits per baud this controller is using? Sort of want to figure out its bandwidth over the serial.

3. Any other tips would be GOOD TOO!

Hope someone would have some time on their hands and gimme some tips.


William Sturm

The serial commands are the same as the on-line commands from the Software Reference Manual, e.g. J, K, B, R, M1=0, P1=1000, OPEN, CLOSE...

You cannot send program commands unless you open a program buffer with OPEN PROG or OPEN PLC. You then close the buffer and run it with the R or ENA command.

You can get multiple variables with P1..99 This can speed up communications a lot for receiving data.

I don't know if you can easily increase the baud rate. I think they have Ethernet and USB options for the PC/104 card. These are much faster, but more complicated.

If you are serious about using the PMAC, I would highly suggest taking a class at Delta Tau. These are complex and very powerful controls. They are not easy to learn. Once you learn, they are fairly easy to understand.

I'm not sure what you are trying to do your GUI in, VB? C++?

I've used the Pcomm32 before in VB, it worked well. PCOMM32pro is a set of DLL functions is the core development for all Delta Tau host computer software. These PCOMM32 libraries are available for the development of host computer software under C++, Visual Basic, LabView and many other software development environments.

This is link to the manual which shows the commands used with pcomm32 drivers: PRO.PDF

In VB I wrote a module that I could call from any form to send or receive data to/from the PMAC/UMAC... not sure how everybody else does it, but it made for clean code and a simple approach.

If this doesn't help give a few more specifics, or call their tech support... I've never had a question either their tech support couldn't answer or their distributors/SI's couldn't answer...

(818) 717-5656 tech phone #.

Ken Emmons Jr.

I have not used the PC104, but I am pretty familiar with PMAC/PMAC2 in general and at the basic level they are the same to program.

In order to do actual work with the PMAC you will want to set up what they call PLC programs and motion programs. I assume that you have done the following:

- Set up your motor/amp parameters and jogged using the PMAC Executive (Or whatever the software is called now). - Set up a coordinate system(s) for your axis (axes).

There are an infinite number of ways to accomplish what you want to do. Perhaps the simplest is to enable the motor with one of the jog commands over serial (I think its J/ or something like that... It means to hold current position). Then you should be able to either jog or fire up a motion program to do your real work (I think the commands "#1 &1 b1r" will assign motor 1 and coordinate system 1 to prog 1 and execute it if I recall correctly....). Really their motion programs (called Progs) are the most powerful way of moving, and will let you do the commands you speak of. These Progs have to be resident in the controller flash when you power up. If your positions change you can write to P variables with your serial port (before executuing motion commands) and then move to these P vars when the motion program is triggered.

Just be wary that your motion program will die if there is an error. I ususally keep a busy line and if it stays busy too long you can query the PMAC registers and find out what is up. Either that or have your operators call you in there and you can wheel in the PMAC executive to probe around.

Like I said, the PMAC is powerful, but it can become infinitely complex if you don't limit the scope of what you are doing to what is necessary. I don't think this philosophy is limited to PMAC though! :eek:)