Verilog HDL: Synchronous State Machine This is a Verilog example that shows the implementation of a state machine. The first CASE statement defines the outputs that are dependent on the value of the state machine variable state. The second CASE statement defines the transitions of state machine and the conditions that control them. download from: http://www.FPGA.com.cn statem.v module statem(clk, in, reset, out); input clk, in, reset; output [3:0] out; reg [3:0] out; reg [1:0] state; parameter zero=0, one=1, two=2, three=3; always @(state) begin case (state) zero: out = 4'b0000; one: out = 4'b0001; two: out = 4'b0010; three: out = 4'b0100; default: out = 4'b0000; endcase end always @(posedge clk or posedge reset) begin if (reset) state = zero; else case (state) zero: state = one; one: if (in) state = zero; else state = two; two: state = three; three: state = zero; endcase end endmodule
本文关键字:程序设计 DSP/FPGA技术,单片机-工控设备 - DSP/FPGA技术
上一篇:CPLD/FPGA初学者入门必看