Intel® Quartus® Prime Standard Edition User Guide: Third-party Synthesis

ID 683796
Date 9/24/2018
Public
Document Table of Contents

2.8.4.6. set_multicycle_path

The multicycle path constraint is specified in the Precision Synthesis software.

Using the set_multicycle_path Constraint

set_multicycle_path <multiplier_value> [-start] [-end] \
-to <to_node_list> -from <from_node_list> -reset_path

The node list can contain clocks, ports, instances, and pins. Multiple elements in the list can be represented using wildcards such as * and ?. Paths without multicycle path definitions are identical to paths with multipliers of 1. To add one additional cycle to the datapath, use a multiplier value of 2. The option start indicates that source clock cycles should be considered for the multiplier. The option end indicates that destination clock cycles should be considered for the multiplier. The default is to reference the end clock.

In the place-and-route Tcl constraints file, the multicycle path setting in the Precision Synthesis software is mapped to a set_multicycle_path setting. The Intel® Quartus® Prime software supports the rise or fall options on this assignment.

The node lists represent top-level ports and/or nets connected to instances (end points of timing assignments). The node lists can contain wildcards (such as *); the Intel® Quartus® Prime software automatically expands all wildcards.

Any multicycle path setting in Precision Synthesis software can be mapped to a setting in the Intel® Quartus® Prime software with a -through specification.