Placement Constraint Examples - 2022.1 English

Vivado Design Suite User Guide: Using Constraints (UG903)

Document ID
UG903
Release Date
2022-06-01
Version
2022.1 English

Placement Constraint Example One

Locate a block RAM at RAMB18_X0Y10 and fix its location.

% set_property LOC RAMB18_X0Y10 [get_cells u_ctrl0/ram0]

Placement Constraint Example Two

Place a LUT in the C5LUT BEL position within a slice and fix its BEL assignment.

% set_property BEL C5LUT [get_cells u_ctrl0/lut0]

Placement Constraint Example Three

Locate input bus registers in ILOGIC cells for shorter input delay.

% set_property IOB TRUE [get_cells mData_reg*]

Placement Constraint Example Four

Combine two small LUTs into a single LUT6_2 that uses both O5 and O6 outputs.

% set_property LUTNM L0 [get_cells {u_ctrl0/dmux0 u_ctrl0/dmux1}]

Placement Constraint Example Five

Prevent the placer from using the first column of block RAMs.

% set_property PROHIBIT TRUE [get_sites {RAMB18_X0Y* RAMB36_X0Y*}]

Placement Constraint Example Six

Prevent the placer from using the clock region X0Y0.

% set_property PROHIBIT TRUE [get_sites -of [get_clock_regions X0Y0]]

Placement Constraint Example Seven

Prevent the placer from using SLR0.

% set_property PROHIBIT TRUE [get_sites -of [get_slrs SLR0]]
Important: When assigning both BEL and LOC properties to a cell, BEL must be assigned before LOC.