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Re: [Xylo-SDR] RFC - Motherboard

On 1/24/06, Eric Ellison <ecellison@comcast.net> wrote:

> The buss stuff really all
> started to unravel when Phil_C said he needed an FPGA on the Radio board due
> to the probable lack of capability of the buss to carry the A/D and other
> high speed sigs to and from the Lionheart. Bill – KD5TFD and I sort of said
> the same thing Saturday:  "If we can't leverage the Lionheart for all buss
> mounted FPGA projects now and in the future, what is the point of the buss?"

Also, this is *not* the primary reason that I would want the LTC2208
board to have its own FPGA.  What needs to be done in the FPGA to
convert/filter/downsample the output of the LTC2208 may not fit into
the Lionheart... or if it does it won't leave any room for anything
else.  Now you could bump up the size of the Cyclone II on the
Lionheart to cover this...but a larger Cyclone II will make the board
much more expensive and it's overkill for other uses like the
Wolfson/TI board that Phil H is working on.  It is more for the reason
of splitting up tasks and putting the horsepower where it is needed
and not overdoing it ($$$) where it is not.  With a FPGA on board, the
LTC2208 can be made to look like the Wolfson/TI board on its output
and data rate... so stuff developed for the Wolfson/TI board can be
reused with the LTC2208 board.

Phil C