From: Nielsen Linus (ext) <"Nielsen>
Date: Mon, 19 Aug 2002 14:15:48 +0200

> I am assuming that the serial line can be configured from
> software to be a simple digital input, which is bi-directional.

Yes it is.

> If this is the case, can we do the following:
>
> Usually have it set as an output, with 1 (+3.3v) on it.
> Connect a capacitor across it and ground, to store some 'juice'
> Use a simple push-to-make switch to ground it through a
> potential divider
> Each (say) 1/100s we could flip the digital line to an input,
> and read it.
> If its 0, the switch is down, if its 1, the switch is not down
> Bingo! we have an input, with just a couple of passive
> components, and no battary

Sounds feasible, yes.

> Can someone who has studied the schematics/ knows the SH2
> processor tell me if this is possible?

I can't see a reason why it shouldn't work.

/Linus
Received on 2002-08-19