`define UP 0
`define DOWN 0
module up_down_counter(
input clock,
input reset,
input load,
input roll_enable,
input[3:0] load_val,
output reg[3:0] count_out,
output max,
output min
);
parameter up_down = 0;
wire halt = (!roll_enable) & (((count_out == 4'h0) & up_down) | ((count_out == 4'hF) & !up_down));
assign max = (count_out == 4'hF);
assign min = (count_out == 4'h0);
always@(posedge clock or negedge reset) begin
if(!reset)
count_out <= 4'b0;
else if(load)
count_out <= load_val;
else if(~halt)
if(up_down == `UP)
count_out <= count_out + 1'b1;
else
count_out <= count_out - 1'b1;
end
endmodule
