Keith Howell wrote:

> Hi chaps & chap-ettes,
>
> Has anyone else noticed this aspect of the PIC SSP in I2C mode:
>
> 1: When reading data from the SSP, it makes the bus wait
> ((by holding SCL low) until the CPU loads the data into SSPBUF
> and then sets CKP. This is desirable behaviour.
>
> 2: When writing data to the SSP, there is no equivalent wait-state
> insertion. This is not desirable.

I don't think this is in the I2C spec. (I could be wrong, so please
be gentle when flaming ;)

You can find out for sure at these links :
http://www.wasp.co.za/~tjaart/electronicsearch.html

I think the best way to do proper I2C slaving on a PIC, is to use
a Scenix. <VBG> I've also been down the I2C-slave-on-a-PIC road.
Pretty rocky out there.

--
Friendly Regards

Tjaart van der Walt
mailto:tjaart@wasp.co.za

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