4个触发器的eda代码

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1、LIBRARYIEEE;USEIEEE.STD_LOGIC_1164.ALL;USEIEEE.STD_LOGIC_UNSIGNED.ALL;ENTITYTEST9ISPORT(CLK,KEY,RESET,LOAD:INSTD_LOGIC;--2M时钟，计数按键，复位按键，重载按键INTI_NUM:INSTD_LOGIC_VECTOR(0TO3);--计数初值Q1,Q2,Q3,Q4:BUFFERSTD_LOGIC--输出值);ENDENTITYTEST9;ARCHITECTUREBEHAVEOFTEST9ISSIGNALKEY_FLAG:STD_L

2、OGIC;--计数按键被按下或松开标志SIGNALCLK_20Hz:STD_LOGIC;--50ms延时，以躲过计数按键抖动SIGNALQ1N,Q2N,Q3N,Q4N:STD_LOGIC;--D触发器反相端BEGINQ1N<=NOTQ1;Q2N<=NOTQ2;Q3N<=NOTQ3;Q4N<=NOTQ4;CLK20Hz:PROCESS(CLK)--由2M时钟脉冲产生20Hz(50ms)周期VARIABLECNT:INTEGERRANGE0TO100000;BEGINIFCLK'EVENTANDCLK='1'THENIFCNT=100000THENC

3、NT:=0;CLK_20Hz<=NOTCLK_20Hz;ELSECNT:=CNT+1;ENDIF;ENDIF;ENDPROCESSCLK20Hz;FLAG:PROCESS(CLK_20Hz)--每50ms检测一次计数按键的状态BEGINIFCLK_20Hz'EVENTANDCLK_20Hz='1'THENIFKEY='1'ANDKEY_FLAG='0'THENKEY_FLAG<='1';--若按键被按下且标志为0，则标志=1ELSIFKEY='0'ANDKEY_FLAG='1'THENKEY_FLAG<='0';--若按键松开且标志为1，则标志=

4、0ENDIF;ENDIF;ENDPROCESSFLAG;DFF1:PROCESS(KEY_FLAG,RESET,LOAD)--第1个触发器的功能。BEGINIFRESET='1'THENQ1<='0';ELSIFLOAD='1'THENQ1<=INTI_NUM(0);--Q1N<='1';ELSIFKEY_FLAG'EVENTANDKEY_FLAG='1'THENQ1<=NOTQ1;--Q1N<=NOTQ1;ENDIF;ENDPROCESSDFF1;DFF2:PROCESS(Q1N,RESET,LOAD)--第2个触发器的功能。BEGINIFRE

5、SET='1'THENQ2<='0';ELSIFLOAD='1'THENQ2<=INTI_NUM(1);--Q2N<='1';ELSIFQ1N'EVENTANDQ1N='1'THENQ2<=NOTQ2;--Q2N<=NOTQ2N;ENDIF;ENDPROCESSDFF2;DFF3:PROCESS(Q2N,RESET,LOAD)--第3个触发器的功能。BEGINIFRESET='1'THENQ3<='0';ELSIFLOAD='1'THENQ3<=INTI_NUM(2);--Q3N<='1';ELSIFQ2N'EVENTANDQ2N='1'THEN

6、Q3<=NOTQ3;--Q3N<=NOTQ3N;ENDIF;ENDPROCESSDFF3;DFF4:PROCESS(Q3N,RESET,LOAD)--第4个触发器的功能。BEGINIFRESET='1'THENQ4<='0';ELSIFLOAD='1'THENQ4<=INTI_NUM(3);--Q4N<='1';ELSIFQ3N'EVENTANDQ3N='1'THENQ4<=NOTQ4;--Q4N<=NOTQ4N;ENDIF;ENDPROCESSDFF4;DFF5:PROCESS(Q4N,RESET,LOAD)--第4个触发器的功能。BEGINI

7、FRESET='1'THENQ5<='0';ELSIFLOAD='1'THENQ5<=INTI_NUM(4);--Q5N<='1';ELSIFQ3N'EVENTANDQ4N='1'THENQ5<=NOTQ5;--Q5N<=NOTQ5N;ENDIF;ENDPROCESSDFF5;ENDBEHAVE;