Re: assignment 2, huge error

Ed Casas (edc@ece.ubc.ca) Tue, 14 Nov 2000 08:54:43 -0800 

Date: Tue, 14 Nov 2000 08:54:43 -0800
From: Ed Casas <edc@ece.ubc.ca>
Subject: Re: assignment 2, huge error



> >>When I compile my code I get something like 20000 errors all saying
> >>something like this:
> >>
> >>Error : Node'[ram:r1]:30495.IN2'missing source

> I get the same errors, and I do not understand the solution.  What do you
> mean by ensuring that the RAM component is properly mapped to/from the
> accumulator.  Explain.

Make sure every signal is driven exactly once.  Each signal
should be in one and only one of the following categories:

- it's one of the entity's input signals

- it appears on the left hand side of a signal assignment

- it's "connected" to an output of a component by being listed in
the appropriate position in a component instantiation

"Missing source" means that one or more of your signals does not
fall into one of the above categories (i.e. it is not connected
to anything).

You might want to draw a block diagram of your top-level design
and label it with the signal names.

If you are getting this error with a RAM, then it probably means
that the RAM data input is not hooked up to anything.  Examine
the computer's instruction set to figure out how it should be
connected.

-- 
Ed Casas   edc@ece.ubc.ca   http://casas.ece.ubc.ca   +1 604 822-2592