Silabs has a uC, I think it is the C8051F350 but I may be wrong, that has a 24 bit ADC with 1-128 gain PGA and offset DAC (and two 8 bit DACs).
Most their chips are available already soldered to a small development board called Toolstick that typically costs $10. You will also need a $20 base Adapter (the USB programmer/debugger) You can use the demo Keil compiler, but it is severely crippled, so instead I recommend the free SDCC. Silabs has lots of sample software for their chips, and an excellent (free) IDE/debugger that supports Keil, SDCC and other compilers. I do have an article on the wiki on my web site about it www.ko4bb.com I also have a page about a simple audio generator using an 8051 as DDS on my web site that describes the tools I use and how to configure the IDE for SDCC. Didier KO4BB Sent from my BlackBerry Wireless thingy while I do other things... -----Original Message----- From: Jim Lux <jim...@earthlink.net> Sender: time-nuts-boun...@febo.com Date: Fri, 13 Jan 2012 08:37:13 To: <time-nuts@febo.com> Reply-To: Discussion of precise time and frequency measurement <time-nuts@febo.com> Subject: Re: [time-nuts] FE-5680A Mechanical Question On 1/13/12 8:15 AM, Chris Albertson wrote: > On Fri, Jan 13, 2012 at 3:19 AM,<ewkeh...@aol.com> wrote: >> What we know is that you can set the Rb in 7 E-13. Dithering would allow >> even closer setting, the question is what rate will the Rb accept with out >> loosing lock or deterioration of the performance. Some one should explore >> that. I am still waiting to se some aging. Taking the 10 MHz output and than >> use an analog loop and something like a Morion OCXO and you have the best of >> all. >> Digitally controlling the Rb will cut the cost of the control loop in half. >> For $10 in parts and a PC board for less than $10 using Shera like >> controller can be realized. What is needed is some one able to do the PIC. >> If some one is interested and able, please contact me off list. A low cost >> GPS or a 1 pps output of a Tbolt be perfect source. >> Bert Kehren > > Don't use a PIC for the prototype. A desktop PC could work as well > and everyone here already has one. Connect the FE5680 to the PC's > serial port and send commands to adjust it. The PC also needs to be > able to read a voltage. Many already have audio input with 24-bit > ADC chips. > But those audio inputs are almost always AC coupled. Bringing up a question: Does anyone know of a cheap (<$20ish) USB voltage sensor (16 bits or better, ideally).. I can see one of those Atmel USB capable micros (like the one on the Arduino Uno) hooked to a dual slope or successive approximation ADC. There seem to be an amazing number of times that I want something like that. The DATAQ $29 widget is only 10 bits, unfortunately. A USB interface DMM would work nicely, but I haven't found one that's in the under $50 price range. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.