The GPIO yellow blocks should have an option to do DDR I/O, which
will allow you to send out a clock at the IBOB's native rate. You
just have to give it both edges of data in parallel (i.e., for a
clock, you give it a 2-bit unsigned of either '01' binary or '10'
binary).
That said, given the various signal integrity issues involved in
sending a clock from the IBOB to the BEE2, sending out a half-rate
and doubling on the BEE2 isn't really a bad way to go, either.
Thanks,
Henry
Jason Ray wrote:
Admittedly, I have not fully read though all of the replies on this
thread yet, so this might have already been covered....
But, if you want the BEE2 running at the same clock rate as your iBOB's,
I think you'll need to select usr_clk2x on the BEE2 and in the BEE2
model file. Unless there's some other way that Randy & I couldn't find,
the best you can do is connect the LSB of a counter to the iBOB SMA
output. This gives you 1/2 the clk rate of the iBOB. So, you'd be
driving the BEE2 at 1/2 the rate, unless you use usr_clk2x which
multiplies the incoming clock by two to get you back to the same rate.
Is there some way to connect the actual iBOB clock signal to the SMA
GPIO in the model file?
Jason
