AR# 10400: 3.1i WebPACK/Foundation ISE - ECS: How do I lock a pin down on the schematic?
3.1i WebPACK/Foundation ISE - ECS: How do I lock a pin down on the schematic?
Keywords: WebPACK, Foundation, ISE, Schematic, lock, LOC, pin, attribute
General Description: When I use the Schematic Editor in either WebPACK or Foundation ISE, it is sometimes desirable to lock down pins on the schematic rather than using a UCF file. How is this done?
The following steps outline how to add pin locations to the schematic:
1. Within the schematic editor, click on Edit -> Attribute -> Net Attribute.... This will bring up the "Net Attribute Editor" window.
2. Click on the net next to the I/O marker that contains the signal to be locked down. This will put that net name under the "Nets" field in the "Net Attribute Editor"; it will also put attributes in the right window in the "Net Attribute Editor".
3. Click on the "PlaceAndRoute" field in the right window inside the "Net Attribute Editor". Now, in the field next to "PlaceAndRoute" at the top of the "Net Attribute Editor", type in the location constraint as follows:
4. In order to view the location constraint on the schematic, click on Edit -> Attributes -> Net Attribute Window, then click once again on the net next to the I/O marker; the pin location will now appear.
NOTE: Locking down the bits of a bus (nets containing parentheses) is not possible. These nets will need to be locked in the UCF.