Initial commit of OpenSPARC T2 design and verification files.

[OpenSPARC-T2-DV] / design / sys / iop / ccu / rtl / ccu_pulse_shift.v

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// OpenSPARC T2 Processor File: ccu_pulse_shift.v
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`timescale 1 ns / 1 ns

module ccu_pulse_shift (
	rst_n,
	clk,
	shift,
	pulse_in,
	pulse_out	
);

input	rst_n;
input	clk;
input	[4:0] shift;
input	pulse_in;
output	pulse_out;

wire	rst_n;
wire	clk;
wire	[4:0] shift;
wire	pulse_in;
wire 	pulse_out;

reg		[4:0] cnt;			// shift counter
reg 	pulse_event;		// sticky bit set hi once pulse is seen

assign	pulse_out = ((cnt[4:0] == shift[4:0]) && pulse_event)?1'b1:1'b0;
 
always @ (posedge clk) begin
	if (!rst_n) begin 
		cnt <= 5'h00;
		pulse_event <= 1'b0;
	end	else 
		if (pulse_in) begin
			pulse_event <= 1'b1;
			cnt <= 5'h00;
		end else begin
			pulse_event <= pulse_event; 
			cnt <= cnt + 1'b1;
		end	
end


endmodule