In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Philldapill wrote:

Thanks for the detailed reply, Bean. I assume this is what you are talking about?
http://www.parallax.com/Store/Microcontrollers/SXChips/tabid/138/CategoryID/15/List/0/SortField/0/Level/a/ProductID/354/Default.aspx

On the product page, the chip mentions the internal oscillator being from 32kHz to 4MHz. I assume this is a fairly precise oscillator that is set in program? The Propeller, as you know, has an internal RC oscillator, but it's not accurate at all and varies from chip to chip...

If I were to use the SX48, what components would I need to use? I'm sure voltage regulation circuitry would be in order. I need the frequency to be adjustable from 0-45kHz, but if the SX can't do that AND do analog input, I might have to use a PIC. However, I like Parallax and want to support them, so I'd like to go with the SX.

By the way, what I said in the previous post about wanting to update at 10Hz - scratch that. 4Hz update would work just fine, I think. 8-bit PWM would also work well. That gives a resolution of better than 0.4%, so I'd be very happy with that. Would it be possible to start the PWM routine, stop after a certain amount of time/cycles, check the analog inputs, adjust accordingly, restard the PWM and repeat? This way everything could be hard coded and there would be no need for interupts. That is, IF the time spent with the PWM inactive is FAR less than the time spent active.

What do you think about that approach?

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