data types in our applications. While using different type of variables we may need to convert th...
stringOne = String(millis(), DEC); // prints "123456" or whatever the value of millis() is: Serial.println(stringOne); // using a float and the right decimal places: stringOne = String(5.698, 3); Serial.println(stringOne); // using a float and less decimal places to use rounding...
int io=(cmd.substring(2,string_k[0])).toInt(); io_zhixing[io]=0; time_last[io]=millis(); time_low_delay[io]=long(1000.0*((cmd.substring(string_k[0]+1,string_k[1])).toFloat())); time_high_delay[io]=long(1000.0*((cmd.substring(string_k[1]+1)).toFloat())); Serial....
· unsigned long millis() 返回时间函数(单位ms),该函数是指,当程序运行就开始计时并返回记录的参数,该参数溢出大概需要50天时间。 · delay(ms) 延时函数(单位ms)。 · delayMicroseconds(us) 延时函数(单位us)。 数学函数 · min(x, y) 求最小值 · max(x, y) 求最大值 · abs(x) 计算绝对值 ·...
18.1 millis() 18.2 micros() 18.3 delay() 18.4 delayMicroseconds() 十九、数学运算 19.1 min() 19.2 max() 19.3 abs() 19.4 constrain() 19.5 map() 19.6 pow() 19.7 sqrt() 19.8 ceil() 19.9 exp() 19.10 fabs() 19.11 floor() 19.12 fma() ...
#include<Arduino.h>booleanat_exec(char*data,char*keyword,unsigned long time_out){Serial.println(data);Serial.flush();delay(100);// 等待响应unsigned long start=millis();while(Serial.available()<strlen(keyword)){if(millis()-start>time_out)returnfalse;}if(Serial.find(keyword))returntrue;else...
lastRecv = millis(); newDataComing = true; delay(2); } else { now = millis(); if ((now - lastRecv > 100) && (newDataComing == true)) { //Serial.print("recv Data "); //Serial.print(strRecv); boolean isOK = client.publish(ARDUINO_SENSOR, String(strRecv).c_str(), true)...
StringScan_QR(){unsignedlongstarttime; String str =""; Serial3.write(Wakecmd,9);//等待回收信号结束while(Serial3.read() !=0x31); starttime = millis();while(true) {//扫码模块扫出来是会加换行符的str = Serial3.readStringUntil('/r');if((str.length() >=7) || (millis() - startti...
;char username[] = "0783ddd64683f579";char password[] = "bd604gmgit0x7kilc8puok3g2rxsldl2";char outTopic[] = "/up/bd604gmgit0x7kilc8puok3g2rxsldl2/id/99E77F4ECC728656";//set interval for sending messages (milliseconds)const long interval = 8000;unsigned long previousMillis = 0;...
millis() unsigned long millis (void) 毫秒时间 获取机器运行的时间长度, 单位毫秒. 系统最长的记录时间为 9 小时 22 分, 如果超出时间将从 0 开始. 警告: 时间为 unsigned long 类型, 如果用 int 保存时间将得到错误结果: delay(ms) void delay (unsigned long ms) 延时(毫秒) 延时, 单...