vhdl >> resolved/unresolved signal?!

by jozo » Sun, 16 May 2004 21:10:36 GMT

I have made my own type and defined a signal of my tipe:

type my_type is (zero, first, sec, third, fourth);
SIGNAL floor : my_type;

and when I Save and check..., I get the message that says:
floor is multiply driven (or smthn like that).

What does it mean?

I tried writing
SIGNAL floor : resolved my_type;
but than says "can't find resolver smthn...".

What should I do? Please help!

Thank you.




vhdl >> resolved/unresolved signal?!

by Ralf Hildebrandt » Sun, 16 May 2004 22:47:48 GMT



Your write to signal floor from multiplie processes - e.g.:

process(...)
begin
if rising_edge(...) then
floor<= ....
end if;
end process;

floor<= ....

process(....)
begin
if (...) then
floor<=...
end if;
end process;


Don't do this (except you want to design a tri-state multiplexer). Write
to a signal only from one process.


Ralf

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