Altera SDC and TimeQuest API - Manual (Page 70)

2–60 Chapter 2: SDC and TimeQuest API Package and Commands
sdc_ext
SDC and TimeQuest API Reference Manual © December 2009 Altera Corporation
set_net_delay
Usage
set_net_delay -from <names> [-max] [-min] [-to <names>] <delay>
Options
-from <names>: Valid source pins, ports, registers or nets(string patterns are matched
using Tcl string matching)
-max: Specifies maximum delay
-min: Specifies minimum delay
-to <names>: Valid destination pins, ports, registers or nets (string patterns are
matched using Tcl string matching)
<delay>: Required delay
Description
Use the set_net_delay command to query the net delays and perform minimum or maximum timing
analysis across nets. The -from and -to options can be string patterns or pin, port, register, or net
collections. When pin or net collection is used, the collection should include output pins or nets.
If the -to option is unused or if the -to filter is an "*" character, all the output pins and registers on timing
netlist became valid destination points.
When you use the -min option, slack is calculated by looking at the minimum delay on the edge. If you use
-max option, slack is calculated with the maximum edge delay.
Example
project_open my_project
create_timing_netlist
read_sdc
update_timing_netlist
# add min delay constraint
set_net_delay -min 0.160 -from [get_pins inst9|combout] -to \
[get_pins *|dataf]
# add max delay constraint
set_net_delay -max 0.500 -from inst8|combout
# this is same as the previous call
set_net_delay -max 0.500 -from inst8|combout -to *
update_timing_netlist
report_net_delay -panel "Net Delay"