Files
APS/Labs/12. Peripheral units/sys_clk_rst_gen.sv
2023-09-24 10:49:29 +03:00

55 lines
1.2 KiB
Systemverilog

module sys_clk_rst_gen#(
parameter DIV_WIDTH = 4
)(
input logic ex_clk_i,
input logic ex_areset_n_i,
input logic [DIV_WIDTH-1:0] div_i,
output logic sys_clk_o,
output logic sys_reset_o
);
logic [1:0] ex_arstn_buf;
logic [1:0] sys_rstn_buf;
logic ex_arstn_buffered;
assign ex_arstn_buffered = ex_arstn_buf[1];
assign sys_reset_o = !sys_rstn_buf[1];
always_ff @(posedge ex_clk_i or negedge ex_areset_n_i) begin
if(!ex_areset_n_i) begin
ex_arstn_buf <= 2'b0;
end
else begin
ex_arstn_buf <= {ex_arstn_buf[0], 1'b1};
end
end
logic [DIV_WIDTH-1:0] cnt;
logic clk_div;
always_ff @(posedge ex_clk_i or negedge ex_arstn_buffered) begin
if ( ~ex_arstn_buffered ) begin
cnt <= 0;
clk_div <= 0;
end else if ( cnt == 0 ) begin
cnt <= div_i;
clk_div <= !clk_div;
end else begin
cnt <= cnt - 1;
end
end
BUFG clkbuf (.O(sys_clk_o),.I(clk_div));
always_ff @(posedge sys_clk_o or negedge ex_arstn_buffered) begin
if(!ex_arstn_buffered) begin
sys_rstn_buf <= 2'b0;
end
else begin
sys_rstn_buf <= {sys_rstn_buf[0], 1'b1};
end
end
endmodule