Procedure calls in process

[Sylvain Munaut]

Hello all,

I'm trying to understand a weird behavior I'm observing in the simulator.
First I must say it's for a test bench so I don't "really" care about
optimality or synthesis.

I'm calling a procedure from a continuous process (no sensitivitylist) and
the result for the first "iteration" is not what I expect, while all the
others are OK.

The result can be seen here :

http://www.246tnt.com/files/wave.png

It shows two runs of the process that I would expect to be identical ... I've run
the simulation thru both modelsim and simili with same results.

Here is the code snippet : (note it's just a test, not at all real PCI ... )

-- PCI Scenario
process

type dataseq_t is array(integer range <&gt of std_logic_vector(31 downto 0);

-- PCI Read sequence

-- PCI Write sequence
procedure pci_do_write(
w : in integer;
data : in test_t
) is
begin
pci_frame_n <= '0';
pci_ad <= data(0);
wait for 100 ns;
pci_frame_n <= '1';
pci_ad <= data(1);
wait for 100 ns;
pci_frame_n <= 'Z';
pci_ad <= data(2);
end procedure;

constant ts : dataseq_t(0 to 2) := ( x"12345678", x"9ABCDEF0", x"13FF005A" );
begin

-- Reset
wait for 10 ns;
pci_do_write(2, ts);
wait for 200 ns;

end process;


Thanks for any insight ...

Sylvain