On Feb 26, 2007, at 6:39 AM, Jordi Casals wrote:

> Hi,
>
> I use T2 and a micaz platform and now I am trying to connect an I2C
> display to my micaz. I don't have the display yet, but I want to
> have my application ready as soon as possible. I would like to know
> if the writeDone event is signaled even there is no I2C device
> connected to my micaz. I don't know if I there is any problem...
> but Leds.set(0x02) is never called.
>
> Thank you
>
> ______________________________________________________________
> module RandomToI2CC{
>    uses{
>        interface Boot;
>        interface Leds;
>        interface Random;
>        interface Resource;
>        interface I2CPacket<TI2CBasicAddr> as I2C;
>        interface Timer<TMilli> as Timer;
>    }
> }
>
> implementation{
>    uint8_t counter = 0;
>
>    event void Boot.booted(){
>        call Leds.set(0);
>        call Timer.startPeriodic(TIMER_PERIOD);
>    }
>      event void Timer.fired(){
>        if(!(call Resource.isOwner())){
>            if(call Resource.request() == SUCCESS){
>                          }
>        }
>    }
>      event void Resource.granted(){
>        if(call I2C.write(I2C_START | I2C_STOP, 12, sizeof(uint8_t),
> &counter) == SUCCESS){
>            call Leds.set(0x01);
>        }else{
>            call Leds.set (0xFF);
>        }
>    }
>      async event void I2C.readDone(error_t error, uint16_t addr,
> uint8_t length, uint8_t* data){
>          }
>      async event void I2C.writeDone(error_t error, uint16_t addr,
> uint8_t length, uint8_t* data){
>        if(call Resource.release() == SUCCESS){
>            call Leds.set(0x04);
>        }
>        call Leds.set(0x02);
>    }
> }
> ______________________________________________________________


When it comes to I2C, things can be hard to debug. I suggest that you
take a look at how the I2C driver works (chips/atm128/i2c/
Atm128I2CMasterPacketP.nc). If you're not getting a writeDone(), then
chances are the I2C isn't issuing an interrupt in response to your
start condition.

Phil