Describe program control instructions, Computer Engineering

Assignment Help:

Q. Describe Program Control Instructions?

These instructions specify conditions for altering the sequence of program execution or we can say in other words that the content of PC (program counter) register.  PC points to memory location which holds the subsequent instruction to be executed. The alteration in value of PC as a result of execution of control instruction such as BRANCH or JUMP causes a break in sequential execution of instructions. The most common control instructions are as following:

JUMP and BRANCH may be unconditional or conditional. JUMP is an unconditional branch used to implement simple loops. JNE jump not equal is conditional branch instruction. The conditional branch instructions like BRP X and BRN X causes a branch to memory location X if the result of most recent operation is positive or negative correspondingly. If the condition is true PC is loaded with branch address X and next instruction is taken from X otherwise PC is not changed and the subsequent instruction is taken from location pointed by PC. Figure below displays an unconditional branch instruction and a conditional branch instruction if content of AC is zero.

MBR←0; Assign 0 to MBR register

X←2001; Assume X to be an address location 2001

READ X; Read a value from memory location 2001 into AC

BRZ 1007; Branch to location 1007 if AC is zero (Conditional branch on zero)

ADD MBR; add the content of MBR to AC and store result to AC

TRAS MBR; Transfer the contents of AC to MBR 

INC X; Increment X to point to next location 

JUMP 1001;Loop back for further processing.


Related Discussions:- Describe program control instructions

What are the advantages of carrying out simulations, What are the Advantage...

What are the Advantages of carrying out simulations -  saves cost (instead of doing the real thing) -  Safer (scenarios tried out on the simulation first before used in real

Explain about interrupt-processing sequence, Q. Explain about Interrupt-Pro...

Q. Explain about Interrupt-Processing Sequence? The occurrence of an interrupt fires a numbers of events both in processor hardware and software. Figure below displays a sequen

Define the concept of inheritance, Define the concept of Inheritance I...

Define the concept of Inheritance Inheritance is property of reusing the code within the object oriented development. While modelling, we look at the all the classes, and try

Depth in cutoff search, Depth in Cutoff search: The depth is chosen in...

Depth in Cutoff search: The depth is chosen in advance to certify in which the agent does not capture much more long to choose a move: however, if it has longer, well then we

Define encapsulation- object oriented technology, Define Encapsulation- obj...

Define Encapsulation- object-oriented technology Encapsulation also called as information hiding, is the characteristic of separating the external aspects of an object, from t

What is state and state diagram, What is state and state diagram? A sta...

What is state and state diagram? A state is an abstraction of values and links of an object. Set of values and links are grouped together into a state according to the group be

Advanced microprocessor, Write a program to mask bits D3D2D1D0 and to set ...

Write a program to mask bits D3D2D1D0 and to set bits D5D4 and to invert bits D7D6 of the AX register.

Explain about integrated circuit, Q. Explain about integrated circuit? ...

Q. Explain about integrated circuit? An integrated circuit is created on a thin wafer of silicon that is splitted into a matrix of small areas (size of the order of a few m.m.

Explain the working of broad band isdn, Explain the working of broad band I...

Explain the working of broad band ISDN. BISDN Configuration: Figure shows how access to the BISDN network is accomplished. All peripheral devices are interfaced to the acces

Operation of micro-programmed control unit, Micro-instructions are stored i...

Micro-instructions are stored in control memory. Address register for control memory comprises the address of subsequent instruction which is to be read. Control memory Buffer Regi

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd