EDIF 2 0 0, 3 0 0 & 4 0 0
Overview
The EDIF (Electronic Design Interchange Format) Schematic
Format is a universal schematic format developed by the Electronic
Industries Alliance. It is a common schematic format
that is generated by many ECAD suites. There are three
common versions of EDIF in use, with EDIF 2 0 0 and 3 0 0
being the most common in use, as they are the most common
format written out by ECAD software. CAMCAD allows for
the viewing of most EDIF files, as well as the ability to
cross-probe between EDIF and ECAD formats, using the Schematic
Link feature. Advanced features such as back
annotation and hierarchical sheets are fully supported
in EDIF 3 0 0.
Versions Supported
CAMCAD supports the viewing of EDIF 200 and
EDIF 3 0 0 with full backannotation and hierarchical
sheet support by using the Schematic Navigator.
EDIF 4 0 0 is supported in graphical mode only, and is slated
to be fully supported with hierarchical support in future
releases of CAMCAD.
Specific Import Procedures
Loading EDIF data into CAMCAD is a very simple procedure.
- Go to FILE | IMPORT and select
EDIF V 200...400 READ.
- Select the EDIF file you want to load.
- Once the EDIF file has finished loading you will be prompted
to place the EDIF Design. After placing the design in CAMCAD
you are ready to work.
The default rules file is EDIF.in and is found in the CAMCAD
directory. Since the data contained within an EDIF file can
vary from system to system, the EDIF.IN file allows the user
to customize the reader for their specific files. See EDIF.in
File for more information regarding the use of this file.
Tips, Notes and Importing Questions
Where did my Reference Designator Go? Why is it
not in the top of the Edit Query Box?
Properties for given Instances and Nets in EDIF files can
be seen by simply performing an Edit/Query on the
given construct that you are looking for information on.
Note that EDIF properties will now be given a attribute name.
Also note that the Ref Des that is displayed on the top of
the Information box will display an Instance Number (e.g.
I_1234) instead of the true refdes. This is because
of the fact that Reference Designators in EDIF do not always
have to be unique. In all cases, CAMCAD will take the
"designator" property, and assign it to the DESIGNATOR
attribute in for the given instance. Therefore, to find
the Reference Designator, simply look at DESIGNATOR under
the Attribute Section of the Edit/Query Box.
CAMCAD is reporting an Error at line XXXX... Why could
that be?
Edif files generated by third-party writers do not always
meet the specification set down by the EDIF.ORG group. To
test whether your file does have syntax errors, you can download
a free EDIF 3 0 0 syntax checker at the EDIF
Technical Centre. Note that if the file have errors, it
may not load into CAMCAD correctly.
Schematic Navigator
Viewing and Navigating around EDIF 3 0 0 schematic files
is easy with the new Schematic Navigator. The Schematic
Navigator is accessible by clicking on the Schematic Navigator
choice under Tools menu. Note that you must have
an EDIF file already loaded into CAMCAD for the Schematic
Navigator to start. Once you have loaded the Schematic Navigator
up, there are three subwindows visible. Each of them
represent different sets of data:
Sheets - Many EDIF files contain more than a single
sheet. CAMCAD makes it easy for you to switch between
different sheets by using the Sheet Listing at the top of
the Navigator. To switch between Sheets, simply click
on the desired sheet in the menu.
Instance List - The Instance List allows for you to
look at the different Instances of constructs that exist in
the EDIF file. Note that if an Instance exists on two
different sheets, you will be given a choice of the given
instances to pick.
Nets - Displays the Nets in the EDIF file. Note
that again, you will be given a choice of sheets if the Net
occurs on multiple sheets.
Schematic Symbols - Displays the symbols objects/libraries
for the given EDIF file. In this way, you can look at
the different geometries which compromise the instances on
the sheet.
Hierarchical Schematic Designs ../../
When working with a hierarchical design in CAMCAD, there
are three important rules that are followed.
- Proper net names are propagated from the parent page
into the hierarchy
- For each instance of a hierarchy symbol, common net
names will be distinguished by adding "_" followed
by a number.
- For each instance of a hierarchy symbol, common instance
names will be distinguished by adding "_" followed
by a number.
1) Proper net name are propagated from the
parent page into the hierarchy.
From the Parent page, the net name is labled as "CARRY_IN".
From the hierarchical page, we can see the net name is propagated
correctly to be "CARRY_IN".
2) For each instance of a hierarchy symbol,
common net names will be distinguished by adding "_"
followed by a number.
On the first hierarchy sheet, the net
name is "X_BAR_1".
On the second hierarchy sheet, the net
name is "X_BAR_2".
3) For each instance of a hierarchy symbol, common instance
names will be distinguished by adding "_" followed
by a number.
|
