1. Define Microprocessor?
Microprocessor is a multipurpose, programmable, clock-driven, register
based electronic device that reads binary instructions from a storage
device called memory, accepts binary data as input and processes data
according to those instructions, and provides as output.
2. What is Hardware and Software?
The physical components of the system i.e. computer are called Hardware. Group of programs is called software.
3. Why the microprocessor is viewed as a programmable Device?
Microprocessor is programmable because it can be instructed to perform
given tasks within its capability. Microprocessor is designed to
understand and execute many binary instructions.
4. What is Central processing Unit ( CPU ) ? And Write the use of it.
CPU is a heart of the computer. Central processing Unit controls the
operation of the computer. In a microcomputer the CPU is a
microprocessor. The CPU fetches binary coded instructions from memory,
decodes the instructions into a series of simple actions and carries out
these actions in a sequence of steps.
5. What is a chip?
A chip is also called an integrated circuit. Generally it is a small,
thin piece of silicon onto which the transistors making up the
microprocessor have been etched. A chip might be as large as an inch on a
side and can contain tens of millions of transistors. Simpler
processors might consist of a few thousand transistors etched onto a
chip just a few millimeters square.
6. What is mini computer?
Scaled down versions of mainframe computers are often called
minicomputers. The main unit of a minicomputer usually fits in a single
rack or box. A mini computer runs more slowly, works directly with
smaller data words and does not have as much memory as mainframe.
computers of this type are used for business data processing, industrial
control and scientific research
7. What is System Bus?
The System bus is a communication path between the microprocessor and
peripherals. It is nothing but a group of wires to carry bits.
8. What is Address Bus?
The address bus consists of 16, 20, 24 or 32 parallel signal lines. On
these lines the CPU sends out the address of the memory location that is
to be written to or read from. The number of memory locations that the
CPU can address is determined by the number of address lines. If the CPU
has N address lines, then it can directly address 2N memory locations.
Simply, we can say that Address Bus is used to carry the address.
9. What is Data Bus?
The data bus consists of 8, 16, or 32 parallel signal lines. The data
bus lines are bidirectional. This means that the CPU can read data in
from memory or from a port on these lines, or it can send data out to
memory or to a port on these lines. Simply we can say that data bus is
used to carry the data .
10. What is Assembly Language?
A medium of communication with a computer in which programs are written
in mnemonics. Binary instructions are given abbreviated names called
mnemonics, which form the assembly language for a given processor.
11. What is Machine Language?
The binary medium of communication with a computer through a designed set of instructions specific to each computer.
12. Define Embedded Systems:
Embedded systems are those used to control specialized hardware in
which the computer system is installed. Microprocessor is the final
product and is not available for reprogramming to the end user. E.g.
Copying machine
13. What is Bit-Slice processor?
For some Applications , general purpose CPUs such as the 8080 and 6800
are not fast enough or do not have suitable instruction sets. For these
applications ,several manufacturers produce devices which can be used to
build the custom CPU. This family includes 4 bit ALUs, multiplexers,
sequencers and other parts needed for custom building a CPU. The term
slice comes from the fact that these parts can be connected in parallel
to work with 8 bit words, 16- bit words, or 32 bit words.
14. What is microcontroller?
Microcontroller is a Device that includes microprocessor, memory and
I/O signal lines on a single chip, fabricated using VLSI technology.
15. Write about the importance of instruction set of Z80 8bit microprocessor?
Instruction set 158 basic instructions . Instruction set is the most
powerful set among the 8 bit microprocessors. It does not include two
serial I/O instructions. It includes block I/O instructions
16. List the main applications of 8 bit microprocessors?
8 bit microprocessors is used in a variety of applications such as
appliances , automobiles ,industrial process and control applications.
17. Write the uses of microprocessors in Medical Instrumentation field?
Patient Monitoring in Intensive Care Unit, Pathological Analysis and
the measurement of parameters like blood pressure and temperature.
18. Define Real Time Systems :
Real Time Systems are those in which timeliness is as important as the
correctness of the outputs, although this does not mean that they have
to be “fast systems”.
19. List the limitations of 8 bit microprocessor:
Lower Execution Speed
It can address less memory size
Few instructions are available
20. What do you mean ‘ Data Width’?
Data Width is the width of the ALU. An 8 bit ALU can add / subtract/
multiply etc.. two 8 bit numbers . In many cases, the external data bus
is the same width as the ALU, but not always. The 8088 had a 16 bit ALU
and 8 bit bus , while the modern Pentiums fetch data 64 bits at a time
for their 32 bit ALUs.
21. Draw and specify the complete bit configuration of 8085 flag Register?
D7 D6 D5 D4 D3 D2 D1 D0
S Z AC P CY
S- Sign Flag . If D7 =1 , then sign flag is set, otherwise rest.
Z-Zero flag. If ALU operation results in zero, then this flag is set, Otherwise it is reset.
AC-Auxilliary flag. In an arithmetic operation ,when a carry is
generated by digit D3 and passed on to digit D4, the AC flag is set.
Otherwise it is reset.
P-Parity Flag. If the result of an arithmetic or logic operation has an
even number of 1’s then this flag is set. Otherwise it is reset.
CY-Carry Flag. If an arithmetic operation results in a carry, the carry flag is set. Otherwise it is reset.
22. What is compiler?
Compiler is a program that translates English like words of a high
level language into the machine language of a computer. A compiler read a
given program ,called a source code, in its entirely and then
translates the program into the machine language, which is called an
Object Code.
23. List the four operations commonly performed by MPU( Micro processing Unit)?
Memory Read : Reads data (or instructions) from memory.
Memory Write: Writes Data (or instructions) into memory.
I/O Read: Accepts data from input devices.
I/O Write: Sends data to output devices.
24. Write about RST pins in 8085?
In 8085 ,three RST pins are available, such as RST 7.5 ,RST 6.5 , RST
5.5 RST represents Restart Interrupts. These are vectored interrupts
that transfer the program control to specific memory locations. They
have higher priorities than the INTR interrupt. Among these three, the
priority order is 7.5,6.5,5.5.
25. List the control and status signals available in 8085.
----- ------ ---- ALE , RD, WR, IO/M, S1, S2
ALE-Address Latch Enable
-----
RD – Read Control Signal
----
WR – Write Control Signal
---
IO/M - To specify I/O or memory operation
S1 , S2 – Status signals
26. What are the limitations of 8085 MPU?
(i) The lower order address bus of the 8085 microprocessor is
multiplexed (time shared) with the data bus. The buses need to be
demultiplexed.
(ii) Appropriate control signals need to be generated to interface memory and I/O with the 8085.
