[Tinyos-help] Re: Telos I2C and Radio

[Ted Herman]

Cory,

I understand that I2C and Radio cannot be used at the same time on the 
Telos.
So we have a Telos sending on I2C successfully;  the same Telos can also
send and receive on the radio, so long as there is no I2C attached device.
But when we attach an I2C cable, even RfmToLeds won't work.  I looked at
BusArbitration, but it appears to have no low-level manipulations.  Our I2C
generates no interrupts.  Is there some other trick to enabling or 
disabling
I2C so that the radio can work?   Is there some working examplar of
Telos or Tmote application that uses both I2C and the radio?

Ted

Cory Sharp wrote:

>Po-kai,
>
>The unfortunate answer is that if you are using the radio, you are not
>going to have great success or a very good time using the I2C as
>digital output.  The best you will get is to send output signals or
>read input signals while the radio is not in use.  When there is data
>transfer between the the radio and MCU, not only can you not use those
>pins, those pins will be actuated with SPI protocol signals.
>
>Usinh TinyOS 1.1.15, you'd have to use the BusArbitration component to
>acquire those pins and block the radio from using them. 
>BusArbitration is hard to use correctly, and we've fixed it with
>Resources (from TinyOS 2.x) in Moteiv Boomerang.
>
>Cory
>
>  
>