When LogiBLOX or COREGen modules are generated for Viewlogic schematics, they are given a module type of 'Composite'. This is done to allow functional simulations to be done without having to compile the LogiBLOX elements through NGDBUILD; the simulation can use descriptions that are created when the module is created.
However, by using this symbol type, bogus error messages will be reported by two tools. (The LogiBLOX module is called "LOGI" in the following errors)
1) When the Check program is run on the design ('Tools->Check Project' from within Workview Office's ViewDraw, or 'check -p <design>' from a command prompt), the following error will occur for each LogiBLOX component:
Error: Could not load schematic sheet - LOGI.1
But the final summary will give:
Total Errors - 0 and warnings - 0
(assuming all the errors are the bogus LogiBLOX errors)
2) The Viewlogic Navigator gives the following errors for each pin on each LogiBLOX or COREGen module when opening the design:
viewbase-E-413: Error - Schematic Pin Q_OUT on LOGI.1 is not on its symbol. ...
Solution
1
These errors occur because 'composite' means that Viewlogic expects a lower level schematic for this symbol, but with LogiBLOX there is no schematic.
These errors can be safely ignored.
The EDIF written by EDIFNETO will refer to the LogiBLOX name and pins, and NGDBUILD will properly merge the .NGO file produced when the LogiBLOX module was created. The Navigator will still be able to probe the design even though it cannot see the non-existent LogiBLOX schematic.
2
If these bogus error messages really bother you, they can be avoided by changing the LogiBLOX component type to Module.
Push into the symbol and right-click on the background. Change the 'Symbol Type' from 'Composite' to 'Module'.
IMPORTANT: This solution must only be used if you do not plan to do functional simulations without compiling the design through NGDBUILD. If you do not compile the design, all LogiBLOX modules set to Block Type 'Module' will produce X's. This is why the default setting is 'Composite'.
If you are only performing timing simulations, or if you use the Xilinx Functional Simulation tool (see (Xilinx Solution 1985)) for your functional simulations, then LogiBLOX and COREGen symbols can be safely changed to 'Module'.
Was this Answer Record helpful?
AR# 3079
Date
06/13/2002
Status
Archive
Type
General Article
By using this website, I accept the use of cookies.
Learn more