1 Apr, 2007
Hardware / Microprocessor Interview Questions
- What are Software interrupts? -
RST0, RST1, RST2, RST3, RST4, RST5, RST6, RST7.
- Which interrupt has the highest priority? -
TRAP has the highest priority.
- Name 5 different addressing modes? -
Immediate, Direct, Register, Register indirect, Implied addressing modes.
- How many interrupts are there in 8085? -
There are 12 interrupts in 8085.
- What is clock frequency for 8085? -
3 MHz is the maximum clock frequency for 8085.
- What is the RST for the TRAP? -
RST 4.5 is called as TRAP.
- 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.
- 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.
- 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.
- 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.
- Which interrupt is not level-sensitive in 8085? -
RST 7.5 is a raising edge-triggering interrupt.
- 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.
- What are level-triggering interrupt? -
RST 6.5 & RST 5.5 are level-triggering interrupts.
