WHAT DO YOU MEAN BY CACHE TYPE

WHAT DO YOU MEAN BY CACHE TYPE

Caches are distingunished by the kinds of infoemation they store . An instruction or I- cache stores instruction only .while a data or D-ca... 01:01

Caches are distingunished by the kinds of infoemation they store . An instruction or I- cache stores instruction only .while a data or D-cache  store data only .

sepreting the stored data in this way reconignizes the different access behaviour patterns of instructions and data . For example programme tend to involve few write accesses and they often exhibits more temporal and spatial locality than the data they process .

A cache that stores both instruction and data is refered to as unified. A split cache for instruction and a D-cache for data . while a unified cache is simpler a split cache makes it possible to access programme and data concurrrently .

WHAT IS ALU

WHAT IS ALU

ALU   is a combinationl circuits that implements fixed point addition and subtraction typically using the carry - lookahead methods , it is... 00:43

ALU  is a combinationl circuits that implements fixed point addition and subtraction typically using the carry - lookahead methods , it is also implements to a set shift-and-add/subtracted logicalm operation . multipication and division algorithms of the type can be reliazed by addinng  a few operand registers an accumalter AC, a multiplier quetiant register MQ and a multipland dividend registers MD as well as small control unit .

Dataopath units usually contain the addressible register file-in effect a small a high speed RAM to store ALU operands . 

the register file has several IO ports tp allow operands in servel diffrence registers to be accessed simultneous . bit slicing is a usefull techniqs for contructing a large ALU from multiple copies a small ALU slice.

Multicycling allows a small ALU to process large operands at lower hardware cost but more slowly than bit slicing

ADDRESS MODE OR TYPES OF ADDRESS MODES

ADDRESS MODE OR TYPES OF ADDRESS MODES

Addressing mode specify the various ways in which value of operand is accessed . the purpose of an address field is to point to the current... 00:12

Addressing mode specify the various ways in which value of operand is accessed . the purpose of an address field is to point to the current value V(x) of some operand X used by an instrution. the addressing mode of  X effects the following issues .

•  the speed with which V(x) can be accessed by the CPU
• the ease with which V(x) can be specified and altered .

these are following three basic addressing modes also knows as ABSOULTE ADDRESS

(i) Immediate : the data (X) is eighter 8 bits or 16 bit long and part of the instrutions by implication X is constant , as it is undesirable to modify instruction field during excutions.

(ii) Direct :  the n- bit effective address (EA) of data (X) is part of the instructions . thus X corresponds to a variables and its value V(x) can be varied is without modifying the instruction address field .

                                                                                                                                                                

Indirect : the effective address of data (x) is in the some other location. this is an useful when it required to change the loaction of X without changing the address field of amny instructions that refer to  X .

types of address modes 

WHAT ARE FPGA

WHAT ARE FPGA

A FPGA is a two dimensinol array of genral purpose logic circuit, called celles or logic block , whose fuctions are programmeble buses. eac... 23:46

A FPGA is a two dimensinol array of genral purpose logic circuit, called celles or logic block , whose fuctions are programmeble buses. each cells are linked to one  anothe rby programmble buses . here cells types are not restricted to gates, it is multiflication circuits capable of reliazing all boolean fuctions of few variables, in a addition cell may also contain one or two flilflop .

FPGA can store the programme that determines the circuit to be implemented in a RAM or PROM in the FPGA chip . the pattern of the data in this configuration memory(CM) determines the cells fuctions are their interconnections wirings. each bit of the CM controls a transistor switch in the targets circuits that can selects some cell fuction or make some connections .

content of CM can be replaced for design changes or to correct the the design errors . thus FPGA can be reprogrammed repeatedly which significally reduces development and manufacturing costs .

EXPLAIN SUBROUTINES

EXPLAIN SUBROUTINES

A subroutine definition is assembled into object code . it is not repicated during assembly rather dynamic link is established between the ... 23:19

A subroutine definition is assembled into object code . it is not repicated during assembly rather dynamic link is established between the subroutian object code and the points in the programme where the subroutine is needed .
A subroutine is a self contained sequence of instruction that performs given computationl task . each time a subroutine is called a branch is executed to the beginings of subroutine to start executing its set of instructions after the subroutine has been executed, a branch is made to back to the main programme.
A CALL subroutine instructions consists of an operation code together with an address that specified that beginings of the subroutine.

1. the address of the next instruction available in the programme counter is a stored tempoary location so the subroutine knows where to return .
2. control is transfred to the begining of the subroutine .
the last instruction of every subroutine is called RETURN , it transfer the return address from the temporary location into the programme counter . due to this a transfer of programme control to the instruction whose address was originally stored in the temporary location return can be stored