Answers Database

FPGA Express 1.2, 2.0: How do you specify slew rate in FPGA Express


Record #1483

Product Family:  Software

Product Line:  Synopsys

Problem Title:
FPGA Express 1.2, 2.0: How do you specify slew rate in FPGA Express


Problem Description:
Keywords: slew, attribute, property, FPGA Express, 1.2, 2.0

Urgency: Standard

Slew-rate can be specified on I/O after the design has been 'implemented' in
FPGA Express.


Solution 1:

FPGA Express 2.0:

After 'implementing' the design, right click on the implemented design in the
project window and select Edit Constraints.

This will bring up the constraints window.

The 'ports' tab will list all the pins for a given design.  There is a column
in this display called 'Slew Rate'.  Selecting the 'Slew Rate' row, which
corresponds to the pin you want, use the pulldown menu to pick the slew rate
you desire.

Note: slew rate can only be specified on ports of type output or inout in
FPGA Express



Solution 2:

FPGA Express 1.2:

After 'implementing' the design, double-click on the implemented design in the
project window.

This will bring up the constraints window.

The 'ports' tab will list all the pins for a given design.  There is a column
in this display called 'pad'.  Selecting the 'pad' row, which corresponds to
the pin you want, select the 'define' option.

A new window will be displayed.  Also, the given row, which corresponds to the
pin of interest will be selected (the row button will be depressed).  In the
new window, there will be item called 'Slew Rate', which is where a 'slow' or
'fast' slew can be specified.  Go to the 'Slew Rate' box and choose 'slow' or
'fast'.  Now, hit the 'ok' button to save your change.


Note: slew rate can only be specified on ports of type output or inout in
FPGA Express



End of Record #1483