The relative grid system has the following characteristics:
- It is also known as the standard grid
- It is sufficient for most RPMs
- It applies to homogeneous RPMs in which all cells in an RPM belong to the
same site type (such as slice, block RAM, or DSP).Note: The tool positions objects in relation to other objects in the same RPM set.
The relative grid is a standard rectangular grid in which each grid element has the same size. For example, the following Verilog code defines an eight-slice-high column with an FD cell in each slice:
(* RLOC = "X0Y0" *) FD sr0 (.C(clk), .D(d[0]), .Q(y[0]));
(* RLOC = "X0Y1" *) FD sr1 (.C(clk), .D(d[1]), .Q(y[1]));
(* RLOC = "X0Y2" *) FD sr2 (.C(clk), .D(d[2]), .Q(y[2]));
(* RLOC = "X0Y3" *) FD sr3 (.C(clk), .D(d[3]), .Q(y[3]));
(* RLOC = "X0Y4" *) FD sr4 (.C(clk), .D(d[4]), .Q(y[4]));
(* RLOC = "X0Y5" *) FD sr5 (.C(clk), .D(d[5]), .Q(y[5]));
(* RLOC = "X0Y6" *) FD sr6 (.C(clk), .D(d[6]), .Q(y[6]));
(* RLOC = "X0Y7" *) FD sr7 (.C(clk), .D(d[7]), .Q(y[7]));