Where are volatile variables stored in memory?

Where are volatile variables stored in memory?

There’s no reason for a volatile variable to be stored in any “special” section of memory. It is normally stored together with any other variables, including non-volatile ones. If some compiler decides to store volatile variables in some special section of memory – there’s nothing to prevent it from doing so.

What is volatile variable How do you declare?

volatile is a qualifier that is applied to a variable when it is declared. It tells the compiler that the value of the variable may change at any time-without any action being taken by the code the compiler finds nearby.

Where volatile is stored?

All random access memory (RAM) other than the CMOS RAM used in the BIOS is volatile. RAM is typically used as a primary storage or main memory in computer systems.

What is volatile byte?

If the volatile variable is bigger than a byte (e.g. a 16 bit int or a 32 bit long), then the microcontroller can not read it in one step, because it is an 8 bit microcontroller. While the variable is read, interrupts need to be disabled, so they can’t mess with the bits, while they are read.

What is volatile global variable?

The keyword volatile is mandated when you want to tell the compiler that variable could change outside of the scope where it’s used, for example a memory mapped variable in an embedded system or a signal handler variable that can change in response to receiving a signal from the OS. [

How do you declare a static variable in C?

The keyword static is used while declaring a static variable.

  1. Syntax:
  2. Example: static int abc=80;
  3. Consider the code to display static keywords function,
  4. Output.
  5. Explanation. In the above code, a function called fun is called.
  6. Some Features of Static Variables.
  7. Consider the code,
  8. Output:

Can a variable be both const and volatile explain with example?

Yes, it is possible. The best example is Status Register in controllers, in the program we should not modify this Status Register so it should be a constant. But this can be changed by the processor or hardware based on the interrupt condition.

Is ROM volatile memory?

ROM is non-volatile memory, which means the information is permanently stored on the chip. Turning off the computer does not have any effect on ROM. Non-volatile memory cannot be changed by users.

Why is main memory volatile?

Primary Memory is the main memory of the computer system. Accessing data from primary memory is faster because it is an internal memory of the computer. The primary memory is most volatile, meaning data in primary memory does not exist if it is not saved when a power failure occurs. RAM.

Why do we use volatile variables in C?

There are two main reasons to uses volatile variables: 1 To interface with hardware that has memory-mapped I/O registers. 2 When using variables that are modified outside the program control flow (e.g., in an interrupt service routine) More

Why are volatile variables stored in special section of memory?

There’s no reason for a volatile variable to be stored in any “special” section of memory. It is normally stored together with any other variables, including non-volatile ones. If some compiler decides to store volatile variables in some special section of memory – there’s nothing to prevent it from doing so.

Why does the compiler not optimize volatile variables?

The compiler will not optimize anything that has to do with the volatile variable. There are two main reasons to uses volatile variables: To interface with hardware that has memory-mapped I/O registers.

When do you use volatile variable in ADC?

volatile is generally used when dealing with external events, like interrupts of hardware related pins. example. reading adc values. const voltile means you can not modify or alter the value of that variable in code. only external event can change the value.