Here is where to get low cost, easy to use DDS generators.

>From a company called Microlinear. Thye make them that go up to
500Khz and have serial inputs that will talk to a PIC.

http://www.microlinear.com

They call them programmable sinewave generators.

Norman


PCS Engineering
Norman Gillaspie
325M Sharon Park Dr. #210
Menlo park, Ca. 94025
Tel 650-854-5263
Fax 650-854-5445
Email norman@pcseng.com


> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of David Covick
> Sent: Tuesday, May 18, 1999 8:54 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: DDS generation
>
>
> Lance,
>
> Currently I building up a surf board for the Analog Devices
> AD9832 (AD9835).
> Prior to this chip I was playing with the Harris HSP45102.  I
> could operated
> the Harris chip all the way up to 10 MHz with the computer, but had
> difficulty using the PIC due to 32 and 64 bit data streams.  The
> AD9832 seem
> more friendly to the PIC and also has a built in 10-bit DAC.
> I've posted a similar request to the list in the past re:DDS and got no
> response.  So, I've been on my own on this project :)
>
> David
>
> -----Original Message-----
> >From: Lance Allen <l.allen@AUCKLAND.AC.NZ>
> >To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
> >Date: Tuesday, May 18, 1999 8:44 PM
> >Subject: DDS generation
> >
> >
> >Has anyone here used the DDS method to generate sinewaves with a PIC?
> >We used a 16c74 running at 8MHz to generate 1Hz to 2000Hz in 1 Hz
> >steps. Great for the original application but now we want to ramp up
> >to 20kHz in 1 Hz steps but we just cant squeeze enough for 20kHz out
> >of the code (now a 16MHz xtal). Has anyone done this?  Some clues for
> >tight code?... please.
> >
> >
>