Friday 27 December 2013

MICROPROCESSORS & MICROCONTROLLERS

MICROPROCESSORS & MICROCONTROLLERS
1.      A microprocessors consists of ALU, Control unit, Array of registers.
2.      The address bus of any microprocessor is always Unidirectional.
3.      The word size of 8085 microprocessor is 8-bit.
4.      The stack pointer register in a microprocessor holds the address of the top of the stack.
5.      The addressing mode used in the instruction PUSH B is Register indirect addressing mode.
6.      The maximum number of seven segment displays that can be connected to 8279 is 16.
7.      PSW stands for Accumulator and flags register contents.
8.      A microprocessor with a 12-bit address bus will be able to access 4K bytes.
9.      In 8085, interrupts except TRAP are disabled by a DI instruction.
10.  EPROM is used as a program memory and RAM as a data memory.
11.  8255 can e programmed into two basic modes they are Bit set/Reset, I/O mode.
12.  Micro processor must wait until the key reach to a steady state is known as key debounce.
13.  Multiple interrupt sources, we use external device called Priority interrupt controller.
14.  Peripheral device directly access to memory. This technique is known as Direct memory access.
15.  In serial communication one bit is transferred at a time over a single line.

16.   Micro controller has on chip peripheral devices. 

0 comments:

Post a Comment