Hi,
Jan-Erik Soderholm wrote:
>Hi and thanks for the replies !
>
>I'v also found the FRAM devices from RAMTRON
>(http://www.ramtron.com/products/datasheets.htm).
>
>Has anyone used them ?
<snip>
Yes, they are nice litte critters, no write delay :)
However in reply to your initial question regarding
SPI vs. IIC it's depedning on the complexity of the total system.

For one pic to one eeram I would never use anything else than SPI as
this is
very easy to implement in s/w and also a bit faster than IIC.=20
Also in this case there's no need for an CS signal ( unless you have
other devices
also using the spi or those pins ).

However when slowly gliding towards more 'advanced' systems, then IIC
starts
to become an more elegant path to persue. There are , as other also
noted,=20
only 2 pins used, it's adressable, and utilises handshaking.

However multimaster designs are considered advanced and tricky to do in
s/w, even in h/w
it requires some thinking :).=20
For this there are ways to take shortcuts with seperate pins for
'handshaking' between the pic's
to simplify the IIC protocol to the expence of more pins.

In short =3D hard to say :)

/Tony

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