Tech Mahindra Foundation Interview Questions and Answers

An ISR that accepts an int argument and returns an int value.

• An ISR (Interrupt Service Routine) is a function that is executed in response to an interrupt.

• The ISR should have a return type of int and accept an int argument.

• The ISR can perform any necessary operations and return an int value.

• Here's an example of an ISR in C language: int myISR(int arg) { // code goes here }

RAM and ROM are types of computer memory. RAM is volatile and used for temporary storage, while ROM is non-volatile and used for permanent storage.

• RAM stands for Random Access Memory and is used for temporary storage of data and programs while the computer is running.

• ROM stands for Read-Only Memory and is used for permanent storage of data and programs that cannot be changed.

• RAM is volatile, meaning that its contents are lost when the computer is turned off, while ROM is non-...read more

Structure is a user-defined data type that groups related variables of different data types. Union is a data type that allows storing different data types in the same memory location.

• Structure allocates memory for all its members separately.

• Union allocates memory for only one member at a time.

• Structure is used when all members need to be accessed at the same time.

• Union is used when only one member needs to be accessed at a time.

• Structure is larger in size than union.

• Union is ...read more

A stack is a data structure that follows the Last-In-First-Out (LIFO) principle.

• Elements are added and removed from the top of the stack.

• Common operations include push (add element), pop (remove element), and peek (access top element).

• Stacks can be implemented using arrays or linked lists.

• Example: Undo/Redo functionality in a text editor.

Stack overflow occurs when the call stack exceeds its maximum limit.

• Stack overflow happens when a function calls itself indefinitely, causing the call stack to fill up.

• It can also occur when a function recursively calls other functions, causing the call stack to exceed its limit.

• Stack overflow can be prevented by optimizing recursive functions or increasing the maximum stack size.

Maskable interrupts are interrupts that can be disabled or enabled by the programmer.

• Maskable interrupts can be controlled by setting or clearing bits in a register.

• They can be used to prioritize interrupts and prevent lower priority interrupts from interrupting higher priority ones.

• Examples of maskable interrupts include keyboard interrupts and timer interrupts.

• Maskable interrupts are different from non-maskable interrupts, which cannot be disabled by the programmer.

Interrupts are signals that temporarily halt the CPU's current task to execute a higher priority task.

• Interrupts are used to handle events that require immediate attention

• They can be hardware or software generated

• Interrupts have a priority level that determines which one is executed first

• Examples include keyboard input, mouse movement, and system calls