RT,想做一个按钮控制的SR04搭配LCD,但是一直报错
这是代码:
#include <LiquidCrystal.h>
#include <SR04.h>
const int Trig = 2;
const int Echo = 3;
const int BUTTON = 7;
LiquidCrystal lcd (12,11,9,8,5,4);
int val = 0;
int old_val = 0;
int state = 0;
void setup () {
pinMode(7,INPUT);
pinMode(2,OUTPUT);
pinMode(3,INPUT);
Serial.begin(9600);
lcd.begin(16,4);
}
void loop () {
val = digitalRead(BUTTON);
if((val == HIGH)&&(old_val == LOW )){
state = 1-state;
delay(10);
}
old_val = val;
if(state == 1) {
digitalWrite(Trig,HIGH);
}else {
digitalWrite(Trig,LOW);
}
digitalWrite(Trig,LOW);
delayMicroseconds(2);
digitalWrite(Trig,HIGH);
delayMicroseconds(10);
digitalWrite(Trig,LOW);
float Distance;
Distance = pulseIn(EchoPin,HIGH)/58.00;
Serial.print(Distance);
Serial.println("CM");
delay(1000);
lcd.write("%.f",Distance);
}
这是错误信息:
Arduino:1.8.2 (Windows 7), 开发板:"Arduino/Genuino Uno"
D:\Documents\Arduino\sketch_apr23a\sketch_apr23a.ino: In function 'void loop()':
sketch_apr23a:37: error: 'EchoPin' was not declared in this scope
Distance = pulseIn(EchoPin,HIGH)/58.00;
^
exit status 1
'EchoPin' was not declared in this scope
在文件 -> 首选项开启
“编译过程中显示详细输出”选项
这份报告会包含更多信息。
这是代码:
#include <LiquidCrystal.h>
#include <SR04.h>
const int Trig = 2;
const int Echo = 3;
const int BUTTON = 7;
LiquidCrystal lcd (12,11,9,8,5,4);
int val = 0;
int old_val = 0;
int state = 0;
void setup () {
pinMode(7,INPUT);
pinMode(2,OUTPUT);
pinMode(3,INPUT);
Serial.begin(9600);
lcd.begin(16,4);
}
void loop () {
val = digitalRead(BUTTON);
if((val == HIGH)&&(old_val == LOW )){
state = 1-state;
delay(10);
}
old_val = val;
if(state == 1) {
digitalWrite(Trig,HIGH);
}else {
digitalWrite(Trig,LOW);
}
digitalWrite(Trig,LOW);
delayMicroseconds(2);
digitalWrite(Trig,HIGH);
delayMicroseconds(10);
digitalWrite(Trig,LOW);
float Distance;
Distance = pulseIn(EchoPin,HIGH)/58.00;
Serial.print(Distance);
Serial.println("CM");
delay(1000);
lcd.write("%.f",Distance);
}
这是错误信息:
Arduino:1.8.2 (Windows 7), 开发板:"Arduino/Genuino Uno"
D:\Documents\Arduino\sketch_apr23a\sketch_apr23a.ino: In function 'void loop()':
sketch_apr23a:37: error: 'EchoPin' was not declared in this scope
Distance = pulseIn(EchoPin,HIGH)/58.00;
^
exit status 1
'EchoPin' was not declared in this scope
在文件 -> 首选项开启
“编译过程中显示详细输出”选项
这份报告会包含更多信息。