always_comb begin b = 1'b0; unique case (a[3:0]) 4'd1: begin b = 1'b1; end 4'd0: begin b = 1'b0; end default: begin end endcase end priority case case块内有优先级,串行比较 (依次比较) always_comb begin priority case (1'b1) a[3]: begin end a[2]: begin end default...
这些赋值类型影响仿真更新赋值语句左侧值的顺序,相对于仿真时那一刻的任何其他仿真活动。阻塞赋值(=)立即更新左侧的变量,使新值可供begin-end语句组中的后续语句使用。“即时更新”有效地仿真了组合逻辑数据流中的值传播行为。 下面的代码片段演示了通过组合逻辑程序块中的多个赋值的组合逻辑数据流。 在这个过程中,变...
,output logic [3:0] result, output logic EQ ); always_comb begin if(oppCode == 3'b010) begin // Problem result <= rf1 - rf2; end else if(oppCode == 3'b101) begin // Problem result <= rf1 + rf2; end else if(oppCode == 3'b111) begin // Problem EQ <= (rf1 == r...
组合逻辑 always_comb begincase(curr_state)s0: beginout1 = 1'b1;out2 = 1'b0;ends1: beginout1 = in1;out2 = 1'b1;ends2: beginout1 = 1'b1;out2 = in2;enddefault: beginout1 = 1'b0;out2 = 1'b0;endendcaseend
always_comb begin b = a; c = b; // c = a end // Example 2 always_comb begin c = b; // starting value of c = previous value of a b = a; // changing b does not re-trigger the always_comb in this time step end
组合逻辑 always_comb begincase(curr_state)s0: beginout1 = 1'b1;out2 = 1'b0;ends1: beginout1 = in1;out2 = 1'b1;ends2: beginout1 = 1'b1;out2 = in2;enddefault: beginout1 = 1'b0;out2 = 1'b0;endendcaseend
问SV代码:如果always_comb构造中的语句不能推断纯粹的组合逻辑EN和所有的数字电路一样，毛刺也是FPGA电路中的棘手问题，它的出现会影响电路工作的稳定性，可靠性，严重时会导致整个数字系统的误动作和逻辑紊乱。 信号在FPGA器件中通过逻辑单元连线时，一定存在延时。延时的大小不仅和连线的长短和逻辑单元的数目有...
14 always_comb begin 15 case (addr) begin 16 0 : begin 17 // This branch executes when addr = 0 18 mux_out = a; 19 end 20 1 : begin 21 // This branch executres when addr = 1 22 mux_out = b; 23 end 24 2 : begin 25 // This branch executes when addr = 2 26 mux_...
input [7:0] B; output [7:0] G; reg [7:0] G; always @(B) begin: BIN2GRAY_LOGIC G = ((B >>> 1) ^ B); // pass end I really don't understand the peculiarities between the different Verilog conversions, here. But it suggests that the use of reg in this example is going...
begin if6.in.data = if1.data; if7.in.data = if1.out.data; end initial begin if1.in.data = 0; #100; $finish; end endmodule Expand Post LikeReply markcurry (Member) 8 years ago I think that this is a bug in Vivado and should be fixed. The always_comb do...