[SOLVED] shared signals in Test Benches ?

im&u said:

Hi all,
I'm trying to write a test bench for a fpga as follows:

...
signal a : std_logic;--connected to input a of fpga
signal b : std_logic;--connected to input b of fpga
...
begin
...

main_tb_process: process
begin
--initialization
a <= '0';
b <= '0';

...
--command1
a <= '1';
...
end process

My question is:
is there any way that I can simplify the step of initialization by writing a procedure that when called resets all fpga inputs ? like this :

procedure init_fpga
begin
a <= '0';
b <= '0';
end procedure;

begin
...
main_tb_process: process
begin
--initialization
init_fpga;

...
--command1
a <= '1';
...
end process

The problem is that I want to keep control of signals a and b in the main process for command1 etc.

PS. I'm doing this because it may be useful when fpga has A LOT of inputs.

Thank you.

Click to expand...

aruipksni said:

The easy thing to do is to initialise signals when they are defined.
Signal mysignal : std_logic := `0';

Click to expand...

aruipksni said:

It will work every time your fpga will be reconfigured and initilised. You can activate prog pin of fpga.of course if you dont want reconfigure youre fpga.then you will to conect all signal to some kind of reset logic. Another aproach will be to built a program that will analyse entire signals asigments and regenerate vhdl code.

Click to expand...

im&u said:

That works if fpga needs to be initialized only once, but what about the case when I want to initialize those signals (init fpga) AGAIN after running some commands ?

like this :

main_tb_process: process
begin
--initialization
init_fpga;

...
--command1
a <= '1';
--check something
...
init_fpga;
--command2
...
end process

Click to expand...

TrickyDicky said:

Code:

procedure init_fpga(x,y : out std_logic) is
begin
  x <= '0';
  y <= '0';
end procedure;


.....

init_fpga(a,b);
init_fpga(c,d);

--etc

Click to expand...

TrickyDicky said:

Then stick with the first option - no outputs and just modify the signals directly.
Yes you can use wait statements like that.

Click to expand...