8085 microprocessor questions II

1. What are Software interrupts? -
   RST0, RST1, RST2, RST3, RST4, RST5, RST6, RST7.
2. Which interrupt has the highest priority? -
   TRAP has the highest priority.
3. Name 5 different addressing modes? -
   Immediate, Direct, Register, Register indirect, Implied addressing modes.
4. How many interrupts are there in 8085? -
   There are 12 interrupts in 8085.
5. What is clock frequency for 8085? -
   3 MHz is the maximum clock frequency for 8085.
6. What is the RST for the TRAP? -
   RST 4.5 is called as TRAP.
7. In 8085 which is called as High order / Low order Register? -
   Flag is called as Low order register & Accumulator is called as High order Register.
8. What are input & output devices? -
   Keyboards, Floppy disk are the examples of input devices. Printer, LED / LCD display, CRT Monitor are the examples of output devices.
9. Can an RC circuit be used as clock source for 8085? -
   Yes, it can be used, if an accurate clock frequency is not required. Also, the component cost is low compared to LC or Crystal.
10. Why crystal is a preferred clock source? -
    Because of high stability, large Q (Quality Factor) & the frequency that doesn’t drift with aging. Crystal is used as a clock source most of the times.
11. Which interrupt is not level-sensitive in 8085? -
    RST 7.5 is a raising edge-triggering interrupt.
12. What does Quality factor mean? -
    The Quality factor is also defined, as Q. So it is a number, which reflects the lossness of a circuit. Higher the Q, the lower are the losses.
13. What are level-triggering interrupt? -
    RST 6.5 & RST 5.5 are level-triggering interrupts.