Page 207 - MDP2020-2

················································································ 명장양성프로젝트 【MDP】 과제발표회 자료집 Ⅱ | 201

clk_cnt <= 0;
end
else
begin
clk_cnt <= clk_cnt + 1;
end
end
end

always @(posedge clk, negedge rst)
begin
if(!rst)
begin
state <= column1;
end
else
begin
if(clk_cnt >= scan_delay - 1)
begin
case(state)
column1 : state = column2;
column2 : state = column3;
column3 : state = column4;
column4 : state = column1;
endcase
end

end
end

always @(posedge clk, negedge rst)
begin
if(!rst)
begin
key_data <= 4'b0000;
end
else
begin
case (state)
column1 : begin
case (key_row)
4'b0001 : key_data <= {4'b0001, i}; //key_1
4'b0010 : key_data <= {4'b0100, i}; //key_4
4'b0100 : key_data <= {4'b0111, i}; //key_7
4'b1000 : key_data <= {4'b1110, i}; //key_*
endcase
end