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Lpc2000

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Re: I2C question

2006-05-04 by Dezheng Tang

Do you have pull-ups on SCK and SDA lines?


--- In lpc2000@yahoogroups.com, "Sutton Mehaffey" <sutton@...> wrote:
>
> Can someone unconfuse me on several I2C issues as I try to 
understand
> the Philips I2C code in the file section?
> 
> On, my design using a LPC2148, I am using Master Transmitter mode 
to
> address a RAM.
> 
> The AA flag: Is it only used to acknowledge data received from the 
RAM
> after reading from I2C0DAT?  I assume that the ACKs received from 
the
> RAM when simply addressing it is not related to AA (but is the SI
> bit).  I noticed in the Philips code that the only AA assertion is
> done after receiving data from the chip.  I also assume that the 
slave
> will always give an ACK after sending it data (by the SI flag).  
Or,
> am I totally off base?
> 
> Also, does SCL run all the time, or just during the data transfer? 
> I'm not seeing a SCL signal at all when I start my code.
> 
> Thanks.
> 
> Sutton
>

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