通过按键控制蜂鸣器工作。
模块框图:
时序图:
代码:
/*1位按键消抖
*/
module key_filter (input wire sys_clk ,input wire sys_rst_n ,input wire key_in ,output reg key_flag
);// 参数定义parameter MAX_CNT_10MS = 500_000 ;localparam IDLE = 4'b0001 ,FILTER_UP = 4'b0010 ,SAMPLING = 4'b0100 ,FILTER_BACK = 4'b1000 ;// reg signal define reg key_in_r1 ; reg key_in_r2 ;reg [18:0] cnt_core ;reg [3:0] state_c ;reg [3:0] state_n ;// wire signal define wire nege ;wire pose ;wire IDLEtoFILTER_UP ;wire FILTER_UPtoIDLE ;wire FILTER_UPtoSAMPLING ;wire SAMPLINGtoFILTER_BACK ;wire FILTER_BACKtoIDLE ;wire filter_done ; /******************************************************************/// reg key_in_r1 ; always @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) key_in_r1 <= 1'b1 ;elsekey_in_r1 <= key_in ;end // reg key_in_r2 ;always @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) key_in_r2 <= 1'b1 ;elsekey_in_r2 <= key_in_r1 ;end // wire nege ;assign nege = ~key_in_r1 && key_in_r2 ;// wire pose ; assign pose = key_in_r1 && ~key_in_r2 ;// reg [3:0] state_c ;always @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) state_c <= IDLE ;elsestate_c <= state_n ;end// reg [3:0] state_n ;always @(*) begincase(state_c)IDLE : if(IDLEtoFILTER_UP)state_n = FILTER_UP ;else state_n = IDLE ;FILTER_UP : if(FILTER_UPtoIDLE)state_n = IDLE ;else if(FILTER_UPtoSAMPLING)state_n = SAMPLING ;else state_n = FILTER_UP ;SAMPLING : if(SAMPLINGtoFILTER_BACK)state_n = FILTER_BACK ;else state_n = SAMPLING ;FILTER_BACK:if(FILTER_BACKtoIDLE)state_n = IDLE ;elsestate_n = FILTER_BACK ;default : state_n = IDLE ;endcaseendassign IDLEtoFILTER_UP = (state_c == IDLE) && (nege) ;assign FILTER_UPtoIDLE = (state_c == FILTER_UP) && (pose) ;assign FILTER_UPtoSAMPLING = (state_c == FILTER_UP) && (filter_done) ;assign SAMPLINGtoFILTER_BACK = (state_c == SAMPLING) && (pose) ;assign FILTER_BACKtoIDLE = (state_c == FILTER_BACK)&& (filter_done) ;// reg [18:0] cnt_core ;always @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) cnt_core <= 19'd0 ;elsecase (state_c)IDLE :cnt_core <= 19'd0 ; FILTER_UP :if(filter_done)cnt_core <= 19'd0 ;else cnt_core <= cnt_core + 1'b1 ;SAMPLING :cnt_core <= 19'd0 ; FILTER_BACK:if(filter_done)cnt_core <= 19'd0 ;else cnt_core <= cnt_core + 1'b1 ;default : cnt_core <= 19'd0 ;endcaseend// wire filter_doneassign filter_done = (cnt_core == MAX_CNT_10MS - 1) ;// output reg key_flagalways @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) key_flag <= 1'b0 ;else if(FILTER_UPtoSAMPLING)key_flag <= ~key_in_r2 ;else key_flag <= 1'b0 ;endendmodule
/*蜂鸣器驱动模块,NPN三极管,beep_en == 1 鸣叫。有源电磁式。1, 初始状态鸣叫,按键每按下一次,蜂鸣器状态翻转。2. 初始状态蜂鸣器工作,响100ms , 不响100ms, 响100ms, 不响300ms.按键每按下一次,蜂鸣器工作状态翻转。
*/
module beep (input wire sys_clk ,input wire sys_rst_n ,input wire key_flag ,output reg beep_en
);// // output reg beep_en// always @(posedge sys_clk or negedge sys_rst_n) begin// if(~sys_rst_n) // beep_en <= 1'b1 ;// else if(key_flag)// beep_en <= ~beep_en ;// end// parameterparameter MAX_CNT_100MS = 5_000_000 ,MAX_CNT_300MS = 15_000_000 ;localparam RING = 3'b001 ,NO_RING_MOD1 = 3'b010 ,NO_RING_MOD2 = 3'b100 ;// reg signal definereg beep_work ;reg [23:0] cnt_core ;reg [2:0] state_c ;reg [2:0] state_n ;reg mod1_flag ;// wire signal definewire RINGtoNO_RING_MOD1 ;wire RINGtoNO_RING_MOD2 ;wire NO_RING_MOD1toRING ;wire NO_RING_MOD2toRING ;wire no_ring_done ;/*****************************************************/// reg beep_work ;always @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) beep_work <= 1'b1 ;else if(key_flag)beep_work <= ~beep_work ;else beep_work <= beep_work ;end// reg [2:0] state_c ;always @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) state_c <= RING ;else state_c <= state_n ;end// reg [2:0] state_n ;always @(*) beginif(beep_work) begincase(state_c)RING : if(RINGtoNO_RING_MOD1)state_n = NO_RING_MOD1 ;else if(RINGtoNO_RING_MOD2)state_n = NO_RING_MOD2 ;elsestate_n = RING ;NO_RING_MOD1: if(NO_RING_MOD1toRING)state_n = RING ;else state_n = NO_RING_MOD1 ;NO_RING_MOD2: if(NO_RING_MOD2toRING)state_n = RING ;else state_n = NO_RING_MOD2 ;default : state_n = RING ;endcaseendelsestate_n = RING ;endassign RINGtoNO_RING_MOD1 = (state_c == RING) && (no_ring_done && (mod1_flag)) ;assign RINGtoNO_RING_MOD2 = (state_c == RING) && (no_ring_done && (!mod1_flag)) ;assign NO_RING_MOD1toRING = (state_c == NO_RING_MOD1) && (no_ring_done) ;assign NO_RING_MOD2toRING = (state_c == NO_RING_MOD2) && (no_ring_done) ;// reg [23:0] cnt_core ;always @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) cnt_core <= 24'd0 ;elseif(beep_work) begincase (state_c)RING : if(no_ring_done)cnt_core <= 24'd0 ;else cnt_core <= cnt_core + 1'b1 ; NO_RING_MOD1: if(no_ring_done)cnt_core <= 24'd0 ;else cnt_core <= cnt_core + 1'b1 ; NO_RING_MOD2: if(no_ring_done)cnt_core <= 24'd0 ;else cnt_core <= cnt_core + 1'b1 ; default : cnt_core <= 24'd0 ;endcaseendelse cnt_core <= 24'd0 ;end// reg mod1_flag ;always @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) mod1_flag <= 1'b1 ;else if(beep_work) beginif((state_c != RING) && (no_ring_done))mod1_flag <= ~mod1_flag ;else mod1_flag <= mod1_flag ;endelse mod1_flag <= 1'b1 ;end// wire no_ring_done;assign no_ring_done = (((state_c != NO_RING_MOD2)&&(cnt_core == MAX_CNT_100MS - 1))||((state_c == NO_RING_MOD2)&&(cnt_core == MAX_CNT_300MS - 1))) ? 1'b1 : 1'b0 ;// output reg beep_enalways @(posedge sys_clk or negedge sys_rst_n) beginif(~sys_rst_n) beep_en <= 1'b1 ;else if(beep_work) beginif(state_c == RING)beep_en <= 1'b1 ;else beep_en <= 1'b0 ;endelse beep_en <= 1'b0 ; endendmodule
module top(input wire sys_clk ,input wire sys_rst_n ,input wire key_in ,output wire beep
);// 例化间连线wire key_flag ;
key_filter key_filter_inst(.sys_clk ( sys_clk ) ,.sys_rst_n ( sys_rst_n ) ,.key_in ( key_in ) ,.key_flag ( key_flag )
);beep beep_inst(.sys_clk ( sys_clk ) ,.sys_rst_n ( sys_rst_n ) ,.key_flag ( key_flag ) ,.beep_en ( beep )
);endmodule
`timescale 1ns/1ns
module test_top();reg sys_clk ;reg sys_rst_n ;reg key_in ;wire beep ;top top_inst(.sys_clk ( sys_clk ) ,.sys_rst_n ( sys_rst_n ) ,.key_in ( key_in ) ,.beep ( beep )
);parameter CYCLE = 20 ;defparam top_inst.key_filter_inst.MAX_CNT_10MS = 50 ;defparam top_inst.beep_inst.MAX_CNT_100MS = 500 ;defparam top_inst.beep_inst.MAX_CNT_300MS = 1500 ;initial beginsys_clk = 1'b1 ;sys_rst_n <= 1'b0 ;key_in <= 1'b1 ;#( CYCLE * 10 ) ;sys_rst_n <= 1'b1 ;#( CYCLE * 10 ) ;#( CYCLE * 3000 ) ;#( CYCLE * 500 ) ; // 检测蜂鸣器状态机是否正常工作。key_in <= 1'b0 ;#( CYCLE * 50 * 3 ); // 按下足够长的时间,第一次按键按下。key_in <= 1'b1 ;#( CYCLE * 3000 ) ;#( CYCLE * 500 ) ; // 检测蜂鸣器状态机是否正常工作。key_in <= 1'b0 ;#( CYCLE * 50 * 3 ); // 按下足够长的时间,第二次按键按下。key_in <= 1'b1 ;#( CYCLE * 3000 ) ;#( CYCLE * 500 ) ; // 检测蜂鸣器状态机是否正常工作。$stop ;endalways #( CYCLE / 2 ) sys_clk = ~sys_clk ;endmodule
仿真: