Help with procedure

[Willem Oosthuizen]

I use the following code in a process, and it works as intended.

if pci_trdyn /= '0' then
while pci_trdyn /= '0' loop
wait for clock_period;
end loop;
wait for clock_period;
else
wait for clock_period;
end if;

I would like to replace this code with

WaitSig(pci_trdyn ,'0',Clock_Period);

where WaitSig is defined as

procedure WaitSig(Sig,State : in std_logic; Clock_Period : in time) is
begin
if Sig /= State then
while Sig /= State loop
wait for clock_period;
end loop;
wait for clock_period;
else
wait for clock_period;
end if;
end procedure;

This does not work. Why? Is it because signals are not updated dynamically
while a procedure executes?
Is there another mechanism I can use to simplify my code?

 

[Egbert Molenkamp]

I think the problem is the procedure

procedure WaitSig(Sig,State : in std_logic; Clock_Period : in time) is

This is equal to:
procedure WaitSig( CONSTANT Sig,State : in std_logic; CONSTANT Clock_Period
: in time) is

and you don't want the constant value ("call by value") but since the value
of the signals
are changed when time progress you want probably the actual value ("call by
reference").
Make this explicit as follows:
procedure WaitSig(SIGNAL Sig,State : in std_logic; Clock_Period : in time)
is
(assuming that Clock_period is a constant value, otherwise add SIGNAL to for
'Clock_period')

Egbert Molenkamp

"Willem Oosthuizen" <willy@asic.co.za> wrote in message
news:bhv98c$mcj$1@ctb-nnrp2.saix.net...

I use the following code in a process, and it works as intended.

if pci_trdyn /= '0' then
while pci_trdyn /= '0' loop
wait for clock_period;
end loop;
wait for clock_period;
else
wait for clock_period;
end if;

I would like to replace this code with

WaitSig(pci_trdyn ,'0',Clock_Period);

where WaitSig is defined as

procedure WaitSig(Sig,State : in std_logic; Clock_Period : in time) is
begin
if Sig /= State then
while Sig /= State loop
wait for clock_period;
end loop;
wait for clock_period;
else
wait for clock_period;
end if;
end procedure;

This does not work. Why? Is it because signals are not updated dynamically
while a procedure executes?
Is there another mechanism I can use to simplify my code?