If you've done sufficient Arduino programming, you'd have seen that there are two ways of defining constants.#defineOne way is to use #define, like#define const_name 3constThe other way is to use the const keyword, likeconst int var_name = 3; Difference between #define and const#define is like a placeholder. The Arduino compiler ... Read More

Just like in C and C++, you need to qualify a variable with the volatile keyword if it can be modified within an interrupt routine.When you qualify a variable as volatile, this is what happens behind the scenes −The compiler gets instructed that the variable should be loaded into the ... Read More

A static variable is a special kind of variable; it is allocated memory 'statically'. Its lifetime is the entire run of the program. It is specific to a function, i.e., only the function that defined it can access it. However, it doesn't get destroyed after the function call ends. It ... Read More

When going through Arduino codes, you may come across some numbers which are followed by either a U or an L or both (or in small caps, u and l). These are formatters, which force integer constants to be of a specific format. U forces an integer constant to be ... Read More

The same operators that are used for comparing integers like , >=, 'A'.ExampleTake a look at the following example.void setup() {    Serial.begin(9600);    Serial.println();    String s1 = "Hello";    String s2 = "hello";    String s3 = "100";    String s4 = "90";    if (s1 > ... Read More

The getBytes() function helps copy the content of a String to a byte array. The syntax is −string1.getBytes(buf, len)where, string1 is the string whose content you want to copy to a byte array, buf is the byte array, andlen is the length of content to be copied.ExampleThe following example illustrates ... Read More

The isControl() function is used to determine if a character is a control character. A control character or a non-printing character (NPC) is a code point (a number) in a character set that does not represent a written symbol. All entries in the ASCII table below code 32 are of ... Read More

In this article, we will see how to interface Arduino with a GSM Module, and ping to a website.You will need the following −An Arduino boardA GSM Module (SIM800C, SIM900A, are popular examples, but you can have any other module as well)A GSM (2G) SIM Card, or a 4G SIM ... Read More

In this article, we will see how to interface Arduino with a GSM Module, and delete all the read SMSes. You will need the following −An Arduino boardA GSM Module (SIM800C, SIM900A, are popular examples, but you can have any other module as well)A GSM (2G) SIM Card, or a ... Read More

In this article, we will see how to interface Arduino with a GSM Module, and read an SMS sent to the SIM card attached to the module.You will need the following −An Arduino boardA GSM Module (SIM800C, SIM900A, are popular examples, but you can have any other module as well)A ... Read More