Re: Black Box - UMCI spec for API posted

Alan,

The credit for the API document goes to Bob Shaver who works
with me. He is also behind the software and getting our algorithm
ideas into the Xilinx chips. My role is mostly hardware and design
for manufacturing, and of course understanding the machine tool
related aspects.

A DDS is a rather simple concept, just a value that gets repetitively
added to a register. The overflow of the register becomes the step
output. Mariss has illustrated to concept quite well in this file
posted in the files section of the Yahoo page for this group:

http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/CIRCUITS/Pulse%20G
en/PULSE%20GENERATOR.pdf

We have been working with DDS's and precision frequency control for
over a decade. Nowadays we end up describing them in Verilog which
gets compiled into a Xilinx pattern. Things do get quite a bit more
complicated when you throw in hardware management of acceleration
and we are still fiddling with that part. Likewise, circular motion
is a whole different problem and at present we intended to rely on
the application program or the API to convert to short linear moves
that get sent to the hardware.

Regards,
Steve Stallings

>Hi Steve,
>
>Looks like you've put in considerable effort! I don't have any
>immediate comments based on my cursory look. I find myself more on

the

>*OTHER END* of API's such as this; Looks like I'm going to do a

"device"

>for our automotive stuff at work.
>
>I see "linear move" in the UMCI_MOVE cmd, for up to 8 axis (!), but I
>don't see any "circular moves"?
>
>Also, I'd like to hear more about the DDS you've implemented.
>
>I'd be most interested in the C++ interface, I'd even be interested

in a

>'C' interface for operation under DOS!
>
>Alan KM6VV