Forum: FPGA, VHDL & Verilog Initializing simulation with data from ILA

von Poor and lonely unused sequential element (Guest)

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I'm looking for a way to assign (or change) certain values to (of) my 
signals during a VHDL simulation. For example I'd like to pause the 
simulation, change the values of my state machine and continue with the 
new values. Is that possible?
I'm aware that you can give signals initial values, however, these 
values are deleted during reset. Furthermore it would mean that I had to 
change all of my VHDL sources - something I'd like to avoid.

What I actually try to to is to investigate the behaviour of a state 
machine I implemented in an FPGA when I feed in the data from my ADCs. 
The system is not behaving in the way I wanted, so I used the integrated 
logic analyzer from Vivado to store the ADCs samples I got + the state 
variables of my control system. I now would like to recreate the exact 
same situation in the simulator to see what is going on in the control 

Any ideas?

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von Cle (Guest)

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Something like force/release in Verilog?

There is also a TCL command 
page 62) if that helps.
If you use VHDL2008 I think there is a force/release keyword as well.

von Poor and lonely unused sequential element (Guest)

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That will do the job I guess, thanks a lot. Unfortunately I have to use 
this from the tcl console and can't use it in the VHDL testbench 
directly (apparently Vivado doesn't support the force release keywords 
from VHDL 2008) but it will suffice.


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