On Thursday 26 June 2008 19:47:57 Peter Clifton wrote:
> -- I2C bus signals
> sda : inout std_logic;
> scl : inout std_logic;
>
> So.. my total NOOB question.. when I make a symbol for that, and
> instantiate it in my schematic, exactly how to I hook up those signals
> to a bi-directional IO buffer.
>
> The IOBUF has explicit I, O and T (direction) connections.
The way I've always done this is to put inout ports on my toplevel VHDL module
file, and then use a constraints file to map the ports to pins. XST has then
correctly inferred that I wanted a tri-state buffer (I think there's a flag
you have to set in the constraints file entry, but it's been a while...)
Cheers,
Peter
--
Peter Brett
Electronic Systems Engineer
Integral Informatics Ltd
Attachment:
signature.asc
Description: This is a digitally signed message part.
_______________________________________________ geda-user mailing list geda-user@xxxxxxxxxxxxxx http://www.seul.org/cgi-bin/mailman/listinfo/geda-user