The whole ISE project (VHDL) can be found here:
Besides ISE project, it also contains two print-screen GIFs, behavioral.gif and post-route.gif.
behavioral.gif shows @40ns : start = 1, data = AAAA at next rising CLK edge CS goes LOW then, SDI serially transmits data (101010...) finally, CS goes HIGH (215ns)
That is exactly what I would expect from the VHDL code.
But the post-route.gif shows something completely different, and I don't know why.
What am I doing wrong?
If I select "tb - behavior (tb.vhd)" in the upper section (and double click Simulate Behavioral Model below) I get the results of behavioral.gif
If I select "uut - DAC_STATE...so on" i get all signals as U, but, as a bonus, I do get internal signals in the list, which I don't get otherwise.
Really annoying..
As Gabor suggested (in the Xilinx forums), post-route requires 100ns delay for the GSR. After changing the first line to "wait for 140 ns;" it now works. Thanks Gabor, once again.
As for the internal signals, that is for another thread.
Ok, if someone else has problems with internal signals, this is how I do it now:
in this GIF
to view internal signals, open Instances and processes panel (and Objects, of course) open "tb", and click on "uut" to see internal signals, as shown here
I'm not saying this is the way to go, but I'm using it now.
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