下列Verilog HDL代码描述中，采用时钟信号clock上升沿和复位信号reset下降沿触发的是（ ）。
A: always @ ( posedge clock, negedge reset ) if ( reset )
B: always @ ( posedge clock, negedge reset ) if ( ! reset )
C: always @ ( clock, reset ) if ( reset )
D: always @ ( posedge clock or negedge reset ) if ( reset==0 )
A: always @ ( posedge clock, negedge reset ) if ( reset )
B: always @ ( posedge clock, negedge reset ) if ( ! reset )
C: always @ ( clock, reset ) if ( reset )
D: always @ ( posedge clock or negedge reset ) if ( reset==0 )
举一反三
- 下列Moore型状态机采用Verilog语言主控时序部分正确的是： A: always@(posedge clk or negedge reset) begin if(!reset) current_state<=s0; else current_state<=next_state; end B: always@(posedge clk ) begin if(!reset) current_state<=s0; else current_state<=next_state; end C: always@(posedge clk t) if(reset) current_state<=s0; else current_state<=next_state; D: always@(posedge clk or negedge reset) if(reset) current_state<=s0; else current_state<=next_state;
- 下列Moore型状态机采用Verilog语言主控时序部分正确的是： A: always@(posedge clk or negedge reset) begin if(!reset) current_state<=s0; else current_state<=next_state; end B: always@(posedge clk ) begin if(!reset) current_state<=s0; else current_state<=next_state; end C: always@(posedge clk t) if(reset) current_state<=s0; else current_state<=next_state; D: always@(posedge clk or negedge reset) if(reset) current_state<=s0; else current_state<=next_state;
- 下列Verilog HDL程序所描述电路功能是（ ）module ShiftReg (Q,Din,CP,CLR_); input Din; //Serial Data inputs input CP, CLR_; //Clock and Reset output reg [3:0] Q; //Register output always @ (posedge CP or negedge CLR_) if (!CLR_) Q <= 4b0000; else begin //Shift right Q[0] <= Din; Q[3:1] <= Q[2:0]; endendmodule
- 阅读下列程序，并说明电路的功能。module half_clk(reset,clk_in,clk_out);input clk_in,reset;output clk_out;reg clk_out;always @(posedge clk_in)beginif(!reset) clk_out=0;else clk_out=~clk_out;endendmodule A: 二分频，同步复位 B: 二分频，异步复位 C: 四分频，同步复位 D: 四分频，异步复位
- 语句 @ (posedge clock, negedge clock) q = d; 的含义是 。 A: 在clock下降沿赋值 B: 在clock上升沿赋值 C: 与@ (clock) q = d;作用相同 D: 该语句是错误的