基本按键,键盘会发送“F0”+“键码”
扩展按键,则发送“E0”+“F0”+“键码”
大家都来试一下吧,一个下午就能搞定!
附程序,晶振频率降至1MHz,用LED输出键值
//==============================================================
module ps2(clk, rst, ps2_clk, ps2_data, data ,data2);
input clk, rst;
inout ps2_clk, ps2_data;
output [10:0] data;
output [10:0] data2;
reg [3:0] i;
reg [10:0] data;//another fifo
reg [10:0] data2;
reg [2:0] ps2_clkr;//用一个fifo来采样ps2_clk信号;
always @(posedge clk)
ps2_clkr <= {ps2_clkr[1:0], ps2_clk};
wire ps2_clk_risingedge = (ps2_clkr[2:1]==2'b01); // now we can detect ps2_clk rising edges
wire ps2_clk_fallingedge = (ps2_clkr[2:1]==2'b10); // and falling edges
always @(posedge clk)
if(rst)
i <= 0;
else
begin
if(ps2_clk_fallingedge)
begin
data2
<= data;
data <= ps2_data;
if(i<10) i <= i+1;
else i <= 0;
end
end
endmodule
最后送上PS2协议中英文文档,非常详细:
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