Minimalist oXs on a ATTiny

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jhsa
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Minimalist oXs on a ATTiny

Post by jhsa » Wed Jul 16, 2014 11:37 am

would this be possible? Imagine that your plane need only to read a voltage and current.
Would it be possible to run the code on a attiny85 for example?
As there is a version of the oxs code for 8Mhz? it wouldn't need a Xtal. There's at least one problem I can see. The ADC0 is on the reset pin.. That means the reset would have to be disabled after programming the chip, right?

Anyway, maybe just a crazy idea but it would probably make things a little bit lighter and smaller if it was possible ;) :)

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Re: Minimalist oXs on a ATTiny

Post by MikeB » Wed Jul 16, 2014 11:50 am

The internal oscillator is probably not accurate enough to guarantee the serial baudrate will always be good enough.
On the X8R2Analog device, this uses the SPort connection. The code measures the incoming baudrate to calibrate the internal oscillator in order to be accurate enough.
A 3-pin resonator would be accurate enough, and cheaper than a Xtal.

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Re: Minimalist oXs on a ATTiny

Post by jhsa » Wed Jul 16, 2014 12:04 pm

Than You could also use a xtal ;)
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Re: Minimalist oXs on a ATTiny

Post by jhsa » Wed Jul 16, 2014 1:31 pm

would the attiny85 have the right timers for the oXs code? sorry if I'm saying nonsense, but I remember that for other project that needed 16 bit timers, the attiny wasn't an option :)

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Re: Minimalist oXs on a ATTiny

Post by davx » Wed Jul 16, 2014 4:35 pm

I'm on a little project of making a smaller OXS with vario, 1 temp and 2 voltages on the same board.
As we use it now, there's many things we don't need (reset switch...) or which are redundant (voltage regulator...).
It's aimed at my future DLG usage, so will be 3.3v.


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Re: Minimalist oXs on a ATTiny

Post by MikeB » Wed Jul 16, 2014 5:25 pm

With the '85, if you use a Xtal/resonator, then you would need to disable the reset input to get 2 analog inputs. This then stops you re-programming the chip, unless you get some sort of bootloader in it!

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Re: Minimalist oXs on a ATTiny

Post by jhsa » Wed Jul 16, 2014 5:41 pm

The question is Would it all fit?
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Re: Minimalist oXs on a ATTiny

Post by MikeB » Wed Jul 16, 2014 5:41 pm

You might consider the Tiny44 (or Tiny84). This has 14 pins.

I'm not sure you will improve much on the size of a Arduino mini unless you use surface mount components.

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Re: Minimalist oXs on a ATTiny

Post by jhsa » Wed Jul 16, 2014 5:45 pm

That was the point of using an attiny with 8 legs ;)
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