organization of registers

1. University of Engineering & Technology Rasul
Submitted By:
Usman Ghani
Submitted To :
Mam Asma Fayyaz

2. GENERAL PURPOSE REGISTERS
General purpose registers are available to store any transient data
required by the program.
For Example
When a program is interrupted its state, i.e the value of the
registers such as the program counter, instruction
register or memory address register - may be saved into the general
purpose registers, ready for recall when the program is ready to start
again.

3. General purpose Register
The registers AX,
BX,CX and DX
are the general
purpose 16-bit
registers.
AX is used as 16-
bit accumulator.
The lower 8-bit
is designated as
AL and higher 8-
bit is designated
as AH. AL can be
used as an 8-bit
accumulator for
8-bit operation.
All data register
can be used as
either 16 bit or 8
bit. BX is a 16 bit
register, but BL
indicates the
lower 8-bit of BX
and BH indicates
the higher 8-bit
of BX.
The register CX
is used default
counter in case
of string and
loop instructions.

4. 4
EXECUTION UNIT – General Purpose Registers
Register Purpose
AX Word multiply, word divide, word I /O
AL Byte multiply, byte divide, byte I/O, decimal arithmetic
AH Byte multiply, byte divide
BX Store address information
CX String operation, loops
CL Variable shift and rotate
DX Word multiply, word divide, indirect I/O
(Used to hold I/O address during I/O instructions. If the result is more than
16-bits, the lower order 16-bits are stored in accumulator and higher order
16-bits are stored in DX register)

5. 5
Intel 8086 Internal Architecture

6. THANKS