help with modelsim error (delay in signal assignment must be

R

ra

Guest
Hi,
I have a schematic where N components output each one a reset signal,
which is given in input to one other component. The line connecting
the resets is something like:

reset <= res_1 or res_2 or res_3 or ... or res_N;

This synthetize fine, but modelsim gives me the following error on the
line above:

Error: router_test_arch.vhd(709): Delay in signal assignment must be
ascending.

Can somebody tell me what to look for? I've no clue.....


RA
 
I have the feeling that the error message has nothing to do with the line
you show.
This error message occurs when you assign to a signal something like:

y <= '0' after 10 ns,
'1' after 5 ns; -- time not ascending;

Correct is
y <= '1' after 5 ns,
'0' after 10 ns;

Egbert Molenkamp

"ra" <ra@ra.com> wrote in message news:LJDOc.54619$8_6.54083@attbi_s04...
Hi,
I have a schematic where N components output each one a reset signal,
which is given in input to one other component. The line connecting
the resets is something like:

reset <= res_1 or res_2 or res_3 or ... or res_N;

This synthetize fine, but modelsim gives me the following error on the
line above:

Error: router_test_arch.vhd(709): Delay in signal assignment must be
ascending.

Can somebody tell me what to look for? I've no clue.....


RA
 
I would have understood that, but I'm not using explicitly any "after"
or "wait". Also, replacing the line I mentioned with just

reset <= res_1

solves the problem.



Egbert Molenkamp wrote:
I have the feeling that the error message has nothing to do with the line
you show.
This error message occurs when you assign to a signal something like:

y <= '0' after 10 ns,
'1' after 5 ns; -- time not ascending;

Correct is
y <= '1' after 5 ns,
'0' after 10 ns;

Egbert Molenkamp

"ra" <ra@ra.com> wrote in message news:LJDOc.54619$8_6.54083@attbi_s04...

Hi,
I have a schematic where N components output each one a reset signal,
which is given in input to one other component. The line connecting
the resets is something like:

reset <= res_1 or res_2 or res_3 or ... or res_N;

This synthetize fine, but modelsim gives me the following error on the
line above:

Error: router_test_arch.vhd(709): Delay in signal assignment must be
ascending.

Can somebody tell me what to look for? I've no clue.....


RA
 
Strange ..

Maybe you can remove (comment) parts of the description to find out when it
is wrong/right. You already did it with the or chain for the reset. Maybe
fine tuning can find the problem.
You may also send me the VHDL description. Maybe I see what the problem is.

Egbert Molenkamp

"ra" <ra@ra.com> wrote in message news:410FDE03.8040107@ra.com...
I would have understood that, but I'm not using explicitly any "after"
or "wait". Also, replacing the line I mentioned with just

reset <= res_1

solves the problem.



Egbert Molenkamp wrote:
I have the feeling that the error message has nothing to do with the
line
you show.
This error message occurs when you assign to a signal something like:

y <= '0' after 10 ns,
'1' after 5 ns; -- time not ascending;

Correct is
y <= '1' after 5 ns,
'0' after 10 ns;

Egbert Molenkamp

"ra" <ra@ra.com> wrote in message
news:LJDOc.54619$8_6.54083@attbi_s04...

Hi,
I have a schematic where N components output each one a reset signal,
which is given in input to one other component. The line connecting
the resets is something like:

reset <= res_1 or res_2 or res_3 or ... or res_N;

This synthetize fine, but modelsim gives me the following error on the
line above:

Error: router_test_arch.vhd(709): Delay in signal assignment must be
ascending.

Can somebody tell me what to look for? I've no clue.....


RA
 

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