Module 1

Mention briefly the advantages of memory segmentation in 8086?

- With the help of memory segmentation a user is able to work with registers having only 16-bits.

- By memory segmentation the various portions of a program can be of more than 68kb.

- The data and the users code can be stored separately allowing for more flexibility.

- Also due to segmentation the logical address range is from 0000H to FFFFH the code can be      loaded    at any location in the memory.

-It allows the memory capacity to be 1MB even though the address associated with individual      instructions are 16 bits wide.

Comparison of 8085 and 8086Comparison of 8085 and 8086

1.Size:-
 8085 is 8 bit microprocessor whereas 8086 is 16 bit microprocessor.
2.Address Bus:-
8085 has 16 bit address bus and 8086 has 20 bit addres bus.
3.Memory:-
8085 can access upto 2^16 = 64 Kb of memory whereas 8086 can access upto
 2^20 = 1 MB of memory.
4.Instruction Queue:-
8085 doesn't have an instruction queue whereas 8086 has instruction queue.
5.Pipelining:-
8085 does not support pipelined architechture whereas 8086 supports pipelined architechture.
6.Multiprocessing Support:-
8085 does not support multiprocessing support whereas 8086 supports.
7.I/O:-
8085 can address 2^8 = 256 I/O's and 8086 can access 2^16 = 65,536 I/O's
8.Airthmetic Support:-
8085 only supports integer and decimal whereas 8086 supports integer, decimal and ASCII arithmetic.
9.Multiplication and Division:-
8085 doesn't support whereas 8086 supports.
10. Operating Modes:-
8085 supports only single operating mode whereas 8086 operates in two modes.
11.External Hardware:-
8085 requires less external hardware whereas 8086 requires more external hardware.
12.Cost:-
The cost of 8085 is low and 8086 is high.
13.Memory Segmentation:-
In 8085, memory space is not segmented but in 8086, memory space is segmented.

Notes on Instruction set
Notes

8086 Interrupts
Notes
Minimum mode and Maximum mode operation of 8086
Notes
Memory Interfacing
Notes
Interfacing with 8059
Notes

80386 Notes

Pentium and Pentium Pro

Pentium III Notes