Multiprocessor Configuration – Question and Answer

1. What are the three basic multiprocessor configurations that the 8086 can support?

1. Coprocessor Configuration
2. Closely Coupled Configuration
3. Loosely Coupled Configuration

2. What do you mean by numeric processor?

8087 is the numeric processor or numeric co-processor. It adds arithmetic, trignometric, exponential and logarithmic instructions to 8086/8088 instruction set for all data types. It supports 16, 32, 64 bit integers, 32, 64, 80 bit floating point and 16 digit BCD data types.

3. What are the advantages of a loosely coupled configuration in a multiprocessor system?

1. Each processor may have a local bus to access local memory or I/O devices so that a greater degree of parallel processing can be achieved.
2. More flexible.
3. Better system throughput by having more than one processor.
4. If any fault occurs in a module, that faulty module can be detected and replaced. So the breakdown of the entire system is avoidable.

4. Name the three bus allocation schemes used in loosely coupled multiprocessor system.

1. Daisy Chaining
2. Polling method
3. Independent Request

5. What are the functional units available in 8087?

Control unit, Numeric execution unit.

6. What are the functional parts of control unit in 8087?

1. Control word register
2. Status word register
3. Data buffer
4. Shared operands queue
5. Addressing and bus tracking
6. Exception pointers

7. What are the functional parts of numeric execution unit?

1. Eight, 80-bit register stack
2. Microcode control unit
3. Exponent module
4. Programmable Shifter
5. Arithmetic modules
6. Temporary registers
7. Shared operand queue

8. Name the data type of 8087.

1. Binary integer – 16 bits, 32 bits, 64 bits
2. Packed decimal number – 80 bits
3. Floating point / Real number – 32 bits, 64 bits, 80 bits

9. How many I/O Channels are available in 8089?

8089 has two internal I/O channels – I/O channel 1 and I/O channel 2.

10. What is the need of BUSY bit in status word of 8087?

The BUSY bit (B₁₅) in status word of 8087 gives the information about numerical execution unit (NEU).
It B₁₅ = 1, the NEU is busy with execution.
0, NEU is free.

• See More : The 8085 Microprocessor Q&A
• See More : 8086 Software Aspects Q&A
• See More : Analog and Digital Models