G'day Arv,

Indeed, being able to talk to it and instruct it would be very handy. A larger device would make it more practical. I was going to use the tiny2313 which has a USART, but it doesn't have an ADC (only a comparator) which means it would have been more difficult to implement the primary function. The tiny2313 has lots of IO pins however, and digital IO as well as PWM and ADC would be very neat as you suggest.

The tiny45 comes to mind as an ideal device for just a few channels. It has 4k of program memory, an ADC and a USI (not a true USART, but could in-theory talk USB with a little work). Peter told me a while back that there is a USB library for AVRs out there, but I haven't investigated it yet. Power and data over USB would be very nice!

Not a bad idea to support the PWM DACs. They are only 8 bit unfortunately, but you could do more in software. Having another counter would make that easier. The mega8 has multiple timers, more analogue channels, a real USART and lots of digital IO pins. Of course there are lots of choices of device. I just picked the tiny13 because it was sitting on my desk from a previous experiment.

Regards,

Alan

Alan

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This begs for bi-directional RS-232 so it can:

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1) Measure voltage and upload it on command from the PC (better time sync management).

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2) Use the AVR D:A to generate voltages, waveforms, frequencies, etc. for many automated testing schemes.

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With all that this them becomes a pocket lab for testing or evaluating almost anything.

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Arv K7HKL