#define 和i..建议大家不要拿 int led=13 与 #define LED 13 作比较,而是应该比较const int LED = 13 和 #define LED 13首先,作为一个严谨的编程习
可以看出,const不能定义系统保留关键字PI,但define可以,这是因为const和define对常量的处理机制不一样,const处理的常量是内存中真实存在的。也就是说const定义的常量占用了内存空间,而define定义的常量只是在编译时,将所有常量名替换成对应的值,上面的例子中,我们可以理解:println中直接打印了3.14159,而不是从内存中提...
这个号在Arduino程序中是用int类型定义的。行3中打算使用一个引脚,将其命名为led;LED_BUILTIN 是一个通过#define语句定义的常量符号,在uno中 LED_BUILTIN 是 13,在rpi pico中,LED_BUILTIN 是25。因此在该rpi pico程序中,行3等价于 int led = 25; Arduino Uno的电路板的PCB俯视图,右侧0、1、2、...、1...
int Digital_Value=0;float temp_Value=0;void setup(){ Serial.begin(9600); //波特率设置为9600 //由于测温范围为0～100℃,输出电压为0～1V,采用内部1.1V参考电压analogReference(INTERNAL);}void loop(){ Digital_Value=analogRead(A0); //读取电压值(数字量) temp_Value=(float)Digital_Value/1023*110.0...
#include <SI4735.h> #define RESET_PIN 16 // Arduino Nano / UNO pin A2 SI4735 rx; void setup() { rx.setup(RESET_PIN, FM_FUNCTION); rx.setFM(8400, 10800, currentFrequency, 10); delay(500); rx.setRdsConfig(3, 3, 3, 3, 3); rx.setFifoCount(1); } char *utcTime; char *...
// SerialMouse sketch #define potXPin 4 #define potYPin 5 void setup() { Serial.begin(9600); } void loop() { int x = analogRead(potXPin); int y = analogRead(potYPin); Serial.print(x,DEC); Serial.print(","); Serial.print(y,DEC); Serial.println(); // send a cr/lf delay(...
#define RECORD_GAP_MICROS 12000 before the line #include <IRremote.hpp> in your .ino file. To see more info supporting you to find the reason for your UNKNOWN protocol, you must enable the line //#define DEBUG in IRremoteInt.h.
TFT//#define LOAD_FONT8N// FreeFonts. Include access to the 48 Adafruit_GFX free fonts FF1 to FF48 and custom fonts#defineLOAD_GFXFF// Comment out the #define below to stop the SPIFFS filing system and smooth font code being loaded// this will save ~20kbytes of FLASH#defineSMOOTH_...
These functions are faster than the previous ones. They differ from the original Arduino functions by the type of pin parameter - they useGPIO_pin_tinstead ofuint8_t(orint). So in your program, you define the pin as GPIO_pin_t pin = DP1; ...
// you could define a variable 'server' like we did with 'ip' and 'mac' // like this, 'byte server[] = { xxx, xxx, xxx, xxx }' // then this line would look like 'if (client.connect(server,80))' if (client.connect("yourwebsite.com",80)) ...