前面的博文中我们介绍了一个arduino中用一片595来控制一位数码管,这里我们介绍一个595来控制两位数码管。两位数码管是应用最广泛的,如交通灯倒计时,计数器等都将用到两位数码管。
两位数码管的动态显示机制可以简单的理解为交错显示,仅仅是我们的视觉停留看起来使我们觉得他们是同时显示的。听起来有点复杂吧,这样吧,我们依然从显示一位数字开始。然后我们再尝试显示两位静态的数字,最后我们再来看,两位数字的动态显示。
一、显示一位数字
代码:
int latchPin=6;
int clockPin=4;
int dataPin=5;
int bitSelect1=2;
int bitSelect2=3;
boolean selectStat=0;
int cseg[10]={0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6F};//0x77,0x7c,?0x39,0x5e,0x79,0x71
int n=0;
void setup () {
// TODO: put your setup code here, to run once:
pinMode(latchPin,OUTPUT);
pinMode(clockPin,OUTPUT);
pinMode(dataPin,OUTPUT);
pinMode(bitSelect1,OUTPUT);
pinMode(bitSelect2,OUTPUT);
}
void loop() {
// TODO: put your main code here, to run repeatedly:
digitalWrite(bitSelect1,0);
digitalWrite(bitSelect2,1);
digitalWrite(latchPin,LOW);
shiftOut(dataPin,clockPin,LSBFIRST,cseg[2]);
digitalWrite(latchPin,HIGH);
delay(20);
}
void chaneBit()
{
selectStat=!selectStat;
digitalWrite(bitSelect1,selectStat);
digitalWrite(bitSelect2,!selectStat);
}
看看效果:
二、显示两位静态的数字
代码:
int latchPin=6;
int clockPin=4;
int dataPin=5;
int bitSelect1=2;
int bitSelect2=3;
boolean selectStat=0;
int cseg[10]={0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6F};//0x77,0x7c,?0x39,0x5e,0x79,0x71
int n=0;
void setup () {
// TODO: put your setup code here, to run once:
pinMode(latchPin,OUTPUT);
pinMode(clockPin,OUTPUT);
pinMode(dataPin,OUTPUT);
pinMode(bitSelect1,OUTPUT);
pinMode(bitSelect2,OUTPUT);
}
void loop() {
// TODO: put your main code here, to run repeatedly:
chaneBit();
digitalWrite(latchPin,LOW);
shiftOut(dataPin,clockPin,LSBFIRST,cseg[4]);
digitalWrite(latchPin,HIGH);
delay(20);
chaneBit();
digitalWrite(latchPin,LOW);
shiftOut(dataPin,clockPin,LSBFIRST,cseg[3]);
digitalWrite(latchPin,HIGH);
delay(20);
}
void chaneBit()
{
selectStat=!selectStat;
digitalWrite(bitSelect1,selectStat);
digitalWrite(bitSelect2,!selectStat);
}
看看效果:
三、两位数字的动态显示
代码:
int latchPin=6;
int clockPin=4;
int dataPin=5;
int bitSelect1=2;
int bitSelect2=3;
boolean selectStat=0;
int cseg[10]={0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6F};//0x77,0x7c,?0x39,0x5e,0x79,0x71
int n=0;
void setup () {
// TODO: put your setup code here, to run once:
pinMode(latchPin,OUTPUT);
pinMode(clockPin,OUTPUT);
pinMode(dataPin,OUTPUT);
pinMode(bitSelect1,OUTPUT);
pinMode(bitSelect2,OUTPUT);
}
void loop() {
// TODO: put your main code here, to run repeatedly:
for(int x=0; x<10; x++)
{
chaneBit();
digitalWrite(latchPin,LOW);
shiftOut(dataPin,clockPin,LSBFIRST,cseg[x]);
digitalWrite(latchPin,HIGH);
delay(20);
chaneBit();
digitalWrite(latchPin,LOW);
shiftOut(dataPin,clockPin,LSBFIRST,cseg[n%10]);
digitalWrite(latchPin,HIGH);
delay(20);
}
n++;
}
void chaneBit()
{
selectStat=!selectStat;
digitalWrite(bitSelect1,selectStat);
digitalWrite(bitSelect2,!selectStat);
}
看看效果:
这里我们采用了595来实现两位数码管的显示,实际和前面没有采用595的原理相同,可以参考前面《proteus仿真arduino控制两位数码管》的博文。