Ashu_ 8086

1. What is internal structure of 8086? 8086 is having 2 different units i.e. BIU(Bus Interface Unit) and EU(Execution Unit), these two units work synchronously. 2. Where 8086 mostly used & tell application of 8086? 8086 is used for general purpose like it is used in traffic signals for control purpose .It's also used for small applications like for calculator,etc 3. Why memory width is not 16-bit? In stead of having 8-bit (same as 8085) memory size of 8086 is 1MB memory size of 8085 is 64KB 2 ^(adresslines)=size of memory (bytes) so adress lines of 8086 are 20 and 8085 is 16 4. What is the difference between 8085 and 8086 in microprocessor 8086 has a special concept called as memory segmentation.It allows parallel processing, while 8085 does not. 5. how many types memory mgt can divided? they are two types. they are two types. they are big endian and little endian. memory is divided into two bank, 1:even bank 2:odd bank. there r two types 1.read only memory 2.random access memory Even bank and odd bank is correct . There are 2 types 1.RAM 2.ROM RAM is used for external storage or for external purpose. ROM is used to store the program, and others 6. Which microprocessor accepts the program written for 8086 without any changes? 8088 is that processor. 80186 7. What does EU do? Execution Unit receives program instruction codes and data from BIU, executes these instructions and store the result in general registers. Basically, 8086 is divided into two parts 1.BIU. 2. EU Execution Unit(EU)Fetch the instruction from Queue(memory(6 byte) in BIU.) and execute it. 8. Which Flags can be set or reset by the programmer and also used to control the operation of the processor? Trace Flag, Interrupt Flag, Direction Flag. 9. Which Segment is used to store interrupt and subroutine return address registers? Stack Segment in segment register is used to store interrupt and subroutine return address registers. 10.What is meant by cross-compiler? A program runs on one machine and executes on another is called as cross-compiler.

Programs which compile on One Machine and Execute on Another machine is called cross compiler. 11.Give examples for Micro controller? Z80, Intel MSC51 &96, Motorola are the best examples of Microcontroller. The answer is:If we make the program in one operating system(os-xp) & if we want to execute/runs on another operating sysrem(oslinux),than we can do it by cross-compiler. 12.What are the different functional units in 8086? Bus Interface Unit and Execution unit, are the two different functional units in 8086. 13.Logic calculations are done in which type of registers? Accumulator is the register in which Arithmetic and Logic calculations are done. 14.What is the position of the Stack Pointer after the POP instruction? The address line is 02 greater than the earlier value. 15.What is the position of the Stack Pointer after the PUSH instruction? The address line is 02 less than the earlier value. Decrement by 2. 16.Which is the tool used to connect the user and the computer? Interpreter is the tool used to connect the user and the tool. 17.What is SIM and RIM instructions? SIM is Set Interrupt Mask. Used to mask the hardware interrupts. RIM is Read Interrupt Mask. Used to check whether the interrupt is Masked or not. 18.Which Stack is used in 8086? FIFO (First In First Out) stack is used in 8086.In this type of Stack the first stored information is retrieved first. 19.What are the various segment registers in 8086? Code, Data, Stack, Extra Segment registers in 8086. 20.What is the Maximum clock frequency in 8086? 5 Mhz is the Maximum clock frequency in 8086. 21.Give example for Non-Maskable interrupts? Trap is known as Non-Maskable interrupts, which is used in emergency condition. 22.Give examples for Maskable interrupts? RST 7.5, RST6.5, RST5.5 are Maskable interrupts. 23.Which interrupts are generally used for critical events? Non-Maskable interrupts are used in critical events. Such as Power failure, Emergency, Shut off etc., 24.What is Non-Maskable interrupts? An interrupt which can be never be turned off (ie.disabled) is known as Non-Maskable interrupt. 25.What is meant by Maskable interrupts?

An interrupt that can be turned off by the programmer is known as Maskable interrupt. 26.What are the various interrupts in 8086? Maskable interrupts, Non-Maskable interrupts. 27.What are the flags in 8086? basically there r two types of interrupti.e.internal and external interrupts.internal interrupts are software inetrrupts which can maskable or nonmaskable where as external interrupts are due to some hardware reset,and are non maskable. 28.On a scale of one to ten, rate me as an interviewer. TRAPS: Give a perfect ?10,? and you?ll seem too easy to please. Give anything less than a perfect 10, and he could press you as to where you?re being critical, and that road leads downhill for you. BEST ANSWER: Once again, never be negative. The interviewer will only resent criticism coming from you. This is the time to show your positivism. However, don?t give a numerical rating. Simply praise whatever interview style he?s been using. If he?s been tough, say ?You have been thorough and tough-minded, the very qualities needed to conduct a good interview.? If he?s been methodical, say, ?You have been very methodical and analytical, and I?m sure that approach results in excellent hires for your firm.? In other words, pay him a sincere compliment that he can believe because it?s anchored in the behavior you?ve just seen. 29.Which Segment is used to store interrupt and subroutine return address registers? Stack Segment in segment register is used to store interrupt and subroutine return address registers. 30.What are the different functional units in 8086? Bus Interface Unit and Execution unit, are the two different functional units in 8086. 31.Which microprocessor accepts the program written for 8086 without any changes? 8088 is that processor. 32.What is the difference between 8086 and 8088? The BIU in 8088 is 8-bit data bus & 16- bit in 8086.Instruction queue is 4 byte long in 8088and 6 byte in 8086. in 8086 instruction buffer q(ibq) is 6bytes address bus 20 bit,data bus 16 bit pin 28 is io'/m ' stand 4 bar. bhe' is present. in 8088

ibq 4 bytes addressbus 16 bit,data bus 8 bit. pin 28 io/m' no bhe'