AVR-Chat

Sorry. it been a while. In your original post, you were going to use it incase the distance was great.

I was saying, using a diff driver on the parent board and a reciever on the child board regardless of distance would be better. Even short distances without a diff driver can cause problems. Just using ground doesnt give you the reliability needed even if the ground loops are isolatd. Grounds can cause problems. If your ground loops are isolated you could recieve EMI in one ground and not the other. Even if the grounds are connected there is a difference between one ground pin on a chip than another. I have experienced this at work.

Any way you do it may work. The question is 'what if'. And how far will you take it?

Brian

--- In AVR-Chat@yahoogroups.com, "Steve Hodge" <steve@...> wrote:
>
> Isn't that what a PCA9517 effectively does (among other things)?   Steve
> 
>  
> 
> From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf
> Of Brian
> Sent: Tuesday, March 31, 2009 4:10 PM
> To: AVR-Chat@yahoogroups.com
> Subject: [AVR-Chat] Re: i2c and twisted pair
> 
>  
> 
> Twisted pair with ground is good. What about diff driver to increase
> reliability and performance?
> 
> Brian
> 
> --- In AVR-Chat@yahoogroups.com <mailto:AVR-Chat%40yahoogroups.com> , "Steve
> Hodge" <steve@> wrote:
> >
> > I would like to use standard shielded Cat 5/6 cable to carry I2C signals
> > between boards, i.e., between microcontrollers on separate boards.
> > Distances are not the question here, because if they end up a factor I'll
> > just use a PCA9517 buffer or something similar, but should someone ask
> they
> > will be of the order of a few to several feet.
> 
> 
> 
>  
> 
> 
> 
> [Non-text portions of this message have been removed]
>