Robert Bosch Interview Guide

Approach: malloc allocates uninitialized memory, calloc allocates and initializes to zero. calloc takes two parameters (num, size), malloc takes one (total size).

Approach: Volatile tells compiler not to optimize the variable. Used for hardware registers and ISR variables. Value can change unexpectedly.

Approach: Pointer holds address, can be NULL, can be reassigned. Reference is alias, cannot be NULL, cannot be reassigned after initialization.

Approach: Virtual functions enable runtime polymorphism. Vtable is a lookup table of function pointers. Each class with virtual functions has its own vtable.

Approach: Undefined behavior. Only first element destructor called. Memory leak for remaining elements. Always use delete[] for arrays.

Approach: 8051 is 8-bit CISC, Harvard architecture. ARM is 32-bit RISC, load-store architecture. ARM has pipelining, better for complex applications.

Approach: Special function that executes when interrupt occurs. Should be short and fast. Saves context, handles event, restores context. Avoid blocking calls in ISR.

Approach: I2C: 2 wires (SDA, SCL), multi-master, addressing, slower. SPI: 4 wires (MOSI, MISO, SCLK, SS), single master, faster, no addressing overhead.

Approach: Real-Time Operating System for time-critical tasks. Provides task scheduling, synchronization, timing guarantees. Use for complex multi-task systems. Bare metal for simple applications.

Approach: Hardware timer that resets system if not periodically refreshed. Recovers from software hangs. Must be kicked regularly in main loop or tasks.

Approach: Automotive Open System Architecture - standardized software architecture for ECUs. Enables reusability, portability, scalability. Layers: Application, RTE, BSW, MCAL.

Approach: Controller Area Network - message-based protocol for automotive. Differential signaling, multi-master, priority-based arbitration. Standard (11-bit ID) and Extended (29-bit ID) frames.

Approach: Classic: static configuration, real-time, OSEK OS, for safety-critical ECUs. Adaptive: dynamic, POSIX OS, SOA-based, for high-performance computing like ADAS.

Approach: Runtime Environment acts as middleware between Application and BSW. Provides standardized interfaces for component communication. Abstracts hardware details.

Approach: Process scheduling (ready queue), memory management (free blocks list), file allocation table, symbol tables in compilers.

Approach: Stack: LIFO - function call stack, undo operations, browser back. Queue: FIFO - print spooler, CPU scheduling, BFS traversal.

Approach: Boyer-Moore Voting Algorithm: maintain candidate and count. If count is 0, update candidate. Increment if match, decrement otherwise. O(n) time, O(1) space.

Approach: Use four boundaries (top, bottom, left, right). Traverse right, down, left, up. Shrink boundaries after each direction. Handle edge cases for single row/column.

Approach: Atomicity (all or nothing), Consistency (valid state), Isolation (concurrent safety), Durability (permanent storage). Essential for reliable transactions.

Approach: TCP: reliable, ordered, connection-oriented (HTTP, email). UDP: fast, no guarantee, connectionless (video streaming, gaming, DNS).

Approach: 1NF: atomic values, no repeating groups. 2NF: 1NF + no partial dependencies. 3NF: 2NF + no transitive dependencies. Reduces redundancy.

Approach: Physical (bits), Data Link (frames), Network (packets), Transport (segments), Session, Presentation, Application. Remember: Please Do Not Throw Sausage Pizza Away.