1 带有异步置位和异步清零的D触发器的真值表:
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2 Verilog代码描述
module DFF_SR(CLK, D, Rd, Sd, Q, QN);
input CLK, D, Rd, Sd;
output Q, QN;
reg Q_DFF;
always @(posedge CLK
or negedge Rd or negedge Sd)begin
if(!Rd)
Q_DFF <= 1'b0;
else if(!Sd)
Q_DFF <= 1'b1;
else
Q_DFF <= D;
end
assign Q = Q_DFF;
assign QN = ~Q_DFF;
endmodule
已经经本人验证,放心使用