From: Andrew Jamieson <ajamiesn_at_optusnet.com.au>
Date: Fri, 11 Oct 2002 23:06:30 +1000

> But what about the software, what do
> you think of this protocol?
>

Seems good. To be clear; the wake-up break frame requires a valid high on
release to continue? This detects simultaneous transmission requests from
remote and Archos? Besides this, it seems quite simple, but given that
there will probably be more comms _to_ the remote rather than _from_ (unless
your a compulsive button pusher :) I still would like to see the Archos as
the master.

> Ok, I don't like drawing power from a processor pin

Neither do I. It's certainly not something I would do if designing the
whole system from scratch - but needs must when the devil drives, and the
Archos design is the devil in so many ways ....

> What do you think of a
> short standard frame that we call "give me power for 100ms"?

I might prefer to see a 'power request' (from the remote) and 'power
enabled' or 'power disabled' (from the Archos) message, that works for the
duration of the connection. Otherwise we are sending more packets than
necessary, and reducing the benifit of the power feature. This would have
the same forwards/backwards compatibility benifits, but reduce the comms
overhead. The only downside would be a standard duration for the power
pulse.

>
> Especially for controllers with limited current driving capabillities
> like the Hitachi, port pin powering is a safety issue. Well, maybe the
> first step is to figure out, how much the voltage will break down if we
> load the controller with 1mA. If it goes below 2,8-3V, it'll be useless.
>

I'll test this myself once I'm back from my holiday. Many of the PIC uC
work down to 2.0V. We'd still be limited by the LCD to a certain extent,
but I would be suprised if we can't find something to work.


> The IRC should be the right place to discuss smaller issues. This here
> is quite right in the mailing list, since it is sorted a little bit on
> topic.

It seems many interested parties are unable to obtain IRC connections. So
it stays here until it becomes unwelcome :)

> What do you think about starting a design document? It could describe
> hardware and software interfaces. Is everybody able to view/edit RTF
> file format?
>

A design brief would be good. RTF is no problem for me, however, this sort
of thing should not really be passed back and forth across the mailer. I'll
be out of discussion for a week, so if you have the time and inclination you
can get this started.

A
Received on 2002-10-11