compute_synchronizer_protection_length (::quartus::sta)

Tcl Package and Version

Syntax

compute_synchronizer_protection_length [-h | -help] [-long_help] [-slack_percentage <slack_percentage> ] -source_clk_freq <source_clk_freq> -synchronizer_clk_freq <synchronizer_clk_freq> [-toggle_rate_percentage <toggle_rate_percentage> ]

Arguments

-h | -help

Short help

-long_help

Long help with examples and possible return values

-slack_percentage <slack_percentage>

The percentage of the synchronizer clock period to use as slack

-source_clk_freq <source_clk_freq>

Source clock frequency

-synchronizer_clk_freq <synchronizer_clk_freq>

Synchronizer clock frequency

-toggle_rate_percentage <toggle_rate_percentage>

Source data toggle rate, set as 12.5% of source clock frequency by default

Description

This command computes the synchronizer protection length using the given source clock frequency and synchronizer clock frequency.
The values should be specified as <frequency><unit> or "<frequency> <unit>", for example 10MHz or "10 MHz".
The values can also be specified as a period instead of a frequency. For example, 100ns.
By default, the source data toggle rate used in the computation is 12.5% of the source clock frequency.
This percentage can be changed by specifying the -toggle_rate_percentage option. For example, -toggle_rate_percentage 12.5.
By default, the slack of synchronizer registers used in the computation is 80% of the synchronizer clock period.
This percentage can be changed by specifying the -slack_percentage option. For example, -slack_percentage 80.
This command returns the computed protection length, or -1 if an acceptable length cannot be found.

Example Usage

compute_synchronizer_protection_length -source_clk_freq 80MHz -synchronizer_clk_freq "50 MHz" -slack_percentage 80
compute_synchronizer_protection_length -source_clk_freq 12.5ns -toggle_rate_percentage 12.5 -synchronizer_clk_freq "500 ns"

Return Value

Code Name

Code

String Return

TCL_OK

0

INFO: Operation successful

Tcl Package and Version	Belongs to ::quartus::sta 1.0
Syntax	`compute_synchronizer_protection_length [-h \| -help] [-long_help]` `[-slack_percentage` <slack_percentage> `]` `-source_clk_freq` <source_clk_freq> `-synchronizer_clk_freq` <synchronizer_clk_freq> `[-toggle_rate_percentage` <toggle_rate_percentage> `]`
Arguments	`-h \| -help`		Short help
	`-long_help`		Long help with examples and possible return values
	`-slack_percentage` <slack_percentage>		The percentage of the synchronizer clock period to use as slack
	`-source_clk_freq` <source_clk_freq>		Source clock frequency
	`-synchronizer_clk_freq` <synchronizer_clk_freq>		Synchronizer clock frequency
	`-toggle_rate_percentage` <toggle_rate_percentage>		Source data toggle rate, set as 12.5% of source clock frequency by default
Description	This command computes the synchronizer protection length using the given source clock frequency and synchronizer clock frequency. The values should be specified as <frequency><unit> or "<frequency> <unit>", for example 10MHz or "10 MHz". The values can also be specified as a period instead of a frequency. For example, 100ns. By default, the source data toggle rate used in the computation is 12.5% of the source clock frequency. This percentage can be changed by specifying the -toggle_rate_percentage option. For example, -toggle_rate_percentage 12.5. By default, the slack of synchronizer registers used in the computation is 80% of the synchronizer clock period. This percentage can be changed by specifying the -slack_percentage option. For example, -slack_percentage 80. This command returns the computed protection length, or -1 if an acceptable length cannot be found.
Example Usage	compute_synchronizer_protection_length -source_clk_freq 80MHz -synchronizer_clk_freq "50 MHz" -slack_percentage 80 compute_synchronizer_protection_length -source_clk_freq 12.5ns -toggle_rate_percentage 12.5 -synchronizer_clk_freq "500 ns"
Return Value	Code Name	Code	String Return
TCL_OK	0	INFO: Operation successful