Re: [CAD_CAM_EDM_DRO] Re: servo vs stepper

Keith Clark wrote:

>Jon, As I understand it the pulse generator is on a DSP chip on the
>motion control board. It is supposedly there outside the computer
>where the pulses are generated. The computer just communicates with
>the motion board throught the serial port.
>
>

Right, I understand this. This is very much how my USC board works,
except it uses the parallel port with IEEE-1284 communications, where
I can pump about 1 million bytes a second between the PC and the board.
Obviously, the serial port is a lot slower than that, maybe something like
11,000 bytes a second at 115K baud. So, I would suspect the velocity
update rate of the Galil board would be limited - that is, how many times
a second the velocity can be changed. With EMC, by default, that is
1000 times a second with the USC, and produces very smooth decrease
in step pulse interval as it is accelerating. I wonder what the update rate
is with your setup?

Jon