Re: TI-H: IR Link
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Min Idzelis wrote:
> I have an interesting point.
> This is how you can do simple, more than two calculator chat. (With a
> working IR transmitter/receiver) If the IR blankets the room, this is
> good. Think about what would happen if you have 1 transmitting
> calculator, and 2 receiving ones. The data transmitted from the
> transmitting calculator would appear on both recieving calculators.
> So you can have a multiperson chat. To keep track of whos saying
> what, a name can be sent with every transmittion. Make sence? Of
> course, there can be no comfirmation messages from the recieving end,
> because if there was, the transmitting calc would recieve 2
> confirmations, and get mixed up. This will make a choppy
> conversation, but it will do. (there are software ways around it)
> (ie, a hotkey to repeat what you just said, incase it got garbled)
> Hope this makes sence... I AM TOTALLY inexpierenced with networks or
> circuits like the ones neccessary for TI-85's.
Hmm...not so stupid, but needs its own protocol. Also, no confirmation
usually means no error correction (as you said), and this would be nice
to have implemented.
How about this:
Let's use the I2C protocol on top of whatever design the IR link uses.
Of course, you might use other protocols, too, with the same link, but
I2C would be a nice way (as it seems to me at least) to connect more
than 2 calcs together. In chat one calc could be the "master", or maybe
more appropriately, "server", to not mix with I2C terms. This calc would
then receive all data from the calcs and send them to everyone, either
through a special I2C address which refers to every calc or individually
to everyone (this would have to be decided, but it's just a software
problem). Maybe the I2C data packets could have a parity bit or other
checksum, and mismatching bytes could be resent (the receiver would ask
the server to resend or vice versa).
Well, this needs some thought, but doesn't seem that difficult. I
believe the hardware is the toughest part of the IR link.
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*** Osma Suominen *** <a href="mailto:ozone@clinet.fi">ozone@clinet.fi</a> *** http://www.clinet.fi/~ozone
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