price and power consumption of YA nanonot

Werner Almesberger werner at openmoko.org
Tue Jan 25 15:32:56 EST 2011


Ron K. Jeffries wrote:
> If feasible, add an infrared LED on the back

I have my set of doubts about IR LEDs. Not so much about the general
usefulness of being able to control devices via IR but more about the
communication process:

Due to its directional nature, communication with a mobile IR device is
quite unreliable. Also, there's usually no readily machine-accessible
feedback mechanism. You need a human to interpret whatever reaction a
command produces, and then make the corresponding
retransmit/proceed/give up decision.

While this may be tolerable for simple remote controls, I would expect
better from a high-function device like the Ben. A much more reliable
approach would be to equip the Ben with an RF transceiver and to make
a small RF-to-IR bug. The bug could go right on the device you wish to
control or it could at least be placed such that its line of sight is
not obstructed.

Now you can actually engineer proper state transitions. The RF
communication is still somewhat unreliable, but it's two-way, so you
have niceties like ARQ, and so on. The IR side always operates under
ideal conditions and thus becomes a lot more reliable.

You asked on IRC about the possibility of making an IR board for the
Ben. I think that would be a good starting point. The Ben is a nice
environment for prototyping such things. Once you have the IR side
worked out, making the RF-to-IR bug shouldn't be too difficult.

> so we can use Nanonote as a powerful and
> (very) smart remote control.

Hmm, for me, this creates a mental image of "Married with Children"
and maybe "The Sopranos". Makes me wonder if the universal remote
control is still much of a status symbol in a customer base that
probably identifies more with the protagonists of "The Big Bang
Theory" ;-)

> Sharism can NOT intelligently make business decision to green light
> (fund) the YA development program before:

Don't you say ! ;-) I think losing sleep over the possibility of
Sharism blowing a vast amount of money on a shakily defined project
is a problem Wolfgang would rather like to have these days ;-)

> -- ?? can we start with schematics Carlos & helpers created
>     about 18 months  ago for a tweaked Ben? ten boards were
>     manufactured. are any of those working or being used?

If the general design will be sufficiently similar to the Ben, then
I think it can't hurt to have another look at the AVT2. In the best
case, it could save some prototyping work.

- Werner




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