Embedded Guru

Volatile keyword in C           The compilation system they always try to reduce the code size and execution time. It is the duty of the programmer to inform the compiler to stop optimizations.Volatile in C informs the compiler to stop optimizing the code . SYNTAX: (How to Use?)           For a variable to be volatile , just write the keyword “volatile” before the data type in the variable definition. For example:           Volatile int temp; If we write the volatile after the data type it is also the same Eg: int volatile temp; Where to use it?           A variable can be declared as a volatile whenever the value of the variable changes unexpectedly or the value can be changed by something beyond the control of the program such as concurrently executing thread or an Interrupt Service Routine. There are three chances where the value of the variable may change unexpectedly:           1.Memory mapped peripheral registers.           2.Global variables modified b

RTOS INTERVIEW QUESTIONS These are some of the interview questions which may be asked on RTOS..... 1.       What is the difference between OS,RTOS,EMBEDDED OS 2.       Scheduling algorithms used in RTOS,OS,EMBEDDED OS 3.       Unilateral Rendezvous,Bilateral Rendezvous,Event Flags,Message Queues,Mailboxes,Shared Memory,Barriers 4.       How do you perform porting? 5.       Difference between embedded C and normal C 6.       Significance of Volatile. 7.       How do we write portable code in embedded systems?

OS INTERVIEW QUESTIONS These are some of the basic interview questions asked on operating system 1.      What is the difference between multitasking,multiprocessing,batch processing ,multiuser? 2.      What is the difference between monolithic and micro kernel? 3.      How to create Dynamic and static library? 4.      How to create a process in linux? 5.      Difference between pipes and named pipes? 6.      All POSIX API for  example what are the API of semaphores? 7.      What are the different types of mutex? 8.      What is conditional variables? 9.      What are barriers? 10.                         What are read write locks? 11.                         Process,Thread. Where Process is beneficial, where thread is beneficial?

1.        How do we create sockets in Linux ,Types of sockets used in Linux 2.        Sockets API’s of server and client 3.        Can we use bind in client side 4.        What are the different types of Bluetooth sockets? 5.        Bluetooth stack 6.        What is piconet 7.        What is scatterenet 8.        What are the different links supported by Bluetooth 9.        Hidden Node problem 10.    Exposed station problem 11.    Why CSMA/CA is used in wifi and why not CSMA/CD? 12.    RTS/CTSS

AVR INTERVIEW QUESTIONS 1.RISC,CISC,VON NEUMANN,HARVARD,MODIFIED HARVARD ARCHITECTURE EXPLAIN 2.Pipelining 3.Pipelining Hazards 4.How do we interface LCD to AVR 5.How do we interface external SRAM to AVR 6. Timing diagram for I2C,SPI 7.Interfacing CAN,Ethernet,USB 8.Interfacing Switches 9. Real time clock(RTC).

ARM INTERVIEW QUESTIONS 1.       What is T,D,M,I in ARM TDMI? 2.       What are the different modes of ARM 3.       What are the different states in ARM 4.       Significance of each state and mode? 5.       Draw CPSR for ARM7TDMI 6.       There is no separate return statement in ARM . then what we will use to return from ARM? 7.       How does stack grows in ARM? 8.       What is the instruction to switch from ARM to Thumb and vice versa? 9.       What are the different coprocessors in ARM? 10.   C Runtime Environment,Linker Descriptor File 11.   Differences between Memory mapped I/O and I/O mapped I/O? 12.   Vector locations in ARM? 13.   Why FIQ is faster than IRQ?