Set external delay
Syntax
set_external_delay ‑from <args> ‑to <args> [‑min] [‑max] [‑add] [‑quiet]
[‑verbose] <delay_value>
Usage
Name | Description |
---|---|
-from
|
Output port |
-to
|
Input port |
[-min]
|
Specifies minimum delay |
[-max]
|
Specifies maximum delay |
[-add]
|
Add to existing external delay |
[-quiet]
|
Ignore command errors |
[-verbose]
|
Suspend message limits during command execution |
<delay_value>
|
External (feedback) delay value |
Description
Sets the external (feedback) delay in nanoseconds (ns) between an output and input port. The external delay is used in the calculation of the PLL/MMCM compensation delay for PLLs/MMCMs with external feedback.
A min or max value can be specified. By default the value specified applies to both min (hold) and max (setup) compensation delays.
The command returns the defined delay.
Arguments
-from
<arg> - (Required) The output port name.
-to
<arg> - (Required) The input port name.
-min
- (Optional) Specifies the delay_value is a minimum delay value for hold time analysis.
-max
- (Optional) Specifies the delay_value is a maximum delay value for setup analysis.
-add
- (Optional) Add the specified delay to the existing external delay value.
-quiet
- (Optional) Execute the command quietly, returning no messages from the command. The command also returns TCL_OK regardless of any errors encountered during execution.
-verbose
- (Optional) Temporarily override any message limits and return all messages from this command.
set_msg_config
command.<delay_value> - (Required) The external delay value specified as nanoseconds (ns). The default value is 0.
Examples
set_external_delay -from [get_ports ClkOut] -to [get_ports ClkFb] 1.0