DS-FND-BSX-PC Xilinx Inc, DS-FND-BSX-PC Datasheet - Page 93

• Manufacturer Part Number: DS-FND-BSX-PC
• Description: FOUNDATION BASE SYS W/SYN EXPRES
• Manufacturer: Xilinx Inc
• Type: Foundation Systemr

Specifications of DS-FND-BSX-PC

• For Use With/related Products: Xilinx Programmable Logic Devices
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 122-1185

Foundation Series 2.1i User Guide
Difference between a Macro and a Schematic
Hierarchy Symbol Changes
Using a Top-down Methodology
The following example explains what happens with the hierarchical
schematic when you create a macro. Assume that the project TEST
contains the schematic sheets TEST1 and TEST2. Create a macro for
the schematic sheet TEST2 as follows:
1.
2.
If you update a hierarchical macro, its symbol is not modified unless
I/O pins change. When pin change, a new symbol is generated based
on the new I/O pins, which may result in incorrect connections on
the schematics that have previously used the symbol. The schematics
that are currently open are automatically updated with the new
symbol when you make the change. Other schematics are updated
when you open them in the Schematic Editor.
When the symbols do not match the previous connections, the wires
are automatically disconnected from that symbol, and a crossed circle
is displayed at the end of these wires. To correct these connections,
you can drag the circles and drop them at the appropriate pins.
You can edit the newly created symbol in the Symbol Editor program
so that it matches the old pin locations.
To implement a top-down design, you first create a symbol for the
hierarchical macro and then create the underlying schematic.
1.
2.
Using the Hierarchy
Current Sheet option, convert the TEST2 schematic into a
macro called MACRO1 in the TEST project library.
The old schematic sheet TEST2 still resides in the project direc-
tory. You can open this schematic file, but there is no longer any
relationship between the TEST2.SCH schematic file and the TEST
project or MACRO1.
Use the Windows Explorer to delete the file TEST2.SCH from the
project directory.
To create an empty symbol, select Tools
from the Schematic Editor.
Click Next.
Create Macro Symbol From
Schematic Design Entry
Symbol Wizard
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