Re: Arbitrary waveform generator

[Coles Sibley <sibley@mit.edu>]

We are using a VMIVME 4145 arbitrary wave form generator card made by VMIC.  There are four
independent outputs.  We are using this VME card to provide an arbitrary ramp function to a
ramped quadrupole for resonant "uniform" extraction when running our ring in pulse stretcher
mode.  The wave form is triggered at 600 hz.  The pulse length is variable, but we retrigger the
wave form at the start of the next cycle.  The DAC output is clocked at 1.5 MHz but can go up to
2 MHz.  The shape of the wave form is changed as desired to "flatten" out the extracted current
profile.  Eventually we would like to add feedback to the wave form to close the loop.

The source code came from Pam Steward at Jlab and Tim Mooney at APS.  I made some minor changes
to their code to load the wave form from some sequencer code which generates the arbitrary wave
form based on some soft record inputs.  A number of modification's could be done to optimize the
downloading of waveforms but it works.

>From what you describe, the VMIVME 4145 would probably work.

"Garrett D. Rinehart" wrote:

> I hesitate to give the device I'm looking for that name because I don't really know if that's
> what it's called.
>
> I need a device which will output a pre-programmed function... just one cycle...
> each time it receives an external trigger. The function covers about 18mS and is
> repeated (triggered) at a 30Hz rate. Anybody got such a device? If so, I'd
> really like to hear from you.
>
> I think this may be what Timo Korhonen is using with the recently
> much-talked-about aao probelm(s). If so, Timo, can you tell me what you have?
>
> Garrett Rinehart
> Intense Pulsed Neutron Source
> Argonne National Laboratory
> 9700 S. Cass Ave
> Argonne, IL  60439
> (630)252-6561