1) Describe the machine of Von Neumann model base:

It is constituted from a supervisory body, from one main memory, one secondary memory, of the interfaces input/output and one logical arithmetical unit.

 

2) What is the MAR?

Memory Address Register, is a registry action to contain addresses, which it acts as from interface between the supervisory body and the rest of the machine of Von Neumann.

 

3) What is the MBR?

Memory Buffer Register, is a registry action to contain given, which it acts as from interface between the supervisory body and the rest of the machine of Von Neumann.

 

4) Describe the physical characteristics of the machine of Von Neumann:

The main memory is formed from 4096 indirizzabili leases therefore through 12 bit in fact 2¹² = 4096 ciascuna of these leases can contain a data or one instruction. Every word after all is constituted from 8 bit dedicates you to 12 the operating code and bit dedicates you to the address in which the address can be found operating or where to find operating same.

 

5) Describe the operation of product between 2 numbers on this machine of Von Neumann:

One of the 2 operandi must be found in the R registry while the 2° operating Address) of the instruction must be found in the cell indicated from part I (puts into effect them. The result occupies 2 words of memory, the high part will come to find in the storage cell while the low part will come to find itself in the R registry.

 

6) Describe the operation of division between 2 numbers on this machine of Von Neumann:

The dividend must find in the storage cell while the divisor is found in the cell aimed from the field of the instruction puts into effect them. The result that is the quotient will come place in the R registry while the rest will come place in the storage cell.

 

7) As one can be carried out difference or sum operation using the same instruction:

This model of the machine of Von Neumann does not make difference between data and instructions, therefore it is also possible to modify an instruction in the course of the program, therefore through a mask the interested instruction can be gone to modify the single COP of the containing lease. In the mentioned case he is sufficient to add one to the COP in order to pass from 5 to 6 and therefore from sum to removal of the storage cell with operating following.

 

8) Describe the direct indirizzamento and its defects:

In the direct indirizzamento the instructions contain the true address in which it is contained since it acts as from operating. The defect is that the programmatore would have to know a priori in which leases of memory would go to situate every element of its program, that does not concur a dynamics management of the memory and consequently is source of memory waste, moreover the such indirizzamento would inhibit the modalities multitasking.

 

9) Describe the indirect indirizzamento:

In this type of indirizzamento, the field of the instruction in issue does not contain the true address of operating bens¬ the address where to find the true address of operating, it is rising of I send back.

 

10) As it changes the machine of Von Neumann in order to implement the indirect indirizzamento:

The instruction comes subdivided in following lives:

bit 1 - 7 ž COP

bit 8 ž 0 = indirizzamento diretto 1 = indirect indirizzamento

bit 9 - 20 ž Address whose contained it has a various one meant to second of the type of indirizzamento.

 

11) What is the meaning for assemblativo language:

It is a possible language that is proposed to render more leggibili little the programs written in language machine approaching themselves the natural language and replacing therefore laddove to the numbers of the sequences of characters who often are acronyms of English words that describe the operation. It renders possible:

to) Replacing to the numbers of the COP one tern of letters

b) To identify of the leases of memory with one label

c) To use the symbolic labels also for the operandi of the instructions.

 

12) Describe instruction LOA PUN *:

It loads the storage cell with the present value in the cell whose address is aimed from PUN.

 

13) Describe instruction LOA PUN:

It loads the storage cell with the present value in cell PUN.

 

14) As one is defined lease costante in language assembler:

Define Constant, is a information that indicates the compiler that that cell contains a data and an instruction therefore cannot be written label DC âvalorè

 

15) As the space for one variable is defined in memory:

FROM it is a information that indicates the compiler that that cell contains a variable data and an instruction therefore cannot be written label FROM

 

16) As a name carrier is defined in memory GIVEN:

It will be allotted in consecutive leases of memory through the definitions:

DATI DC â ' a1 ''

DC â ' a2 ''

........

........

DC â ' an' '

 

17) Describe the indexed indirizzamento:

It is a type of indirizzamento that ago I use of 1 of 7 registries index. The address of operating is given from the sum of the present address in the field of the instruction and the registry the selected index.

 

18) As it changes the machine of Von Neumann in order to implement the indiciato indirizzamento:

The instruction comes subdivided in following lives:

bit 1 - 5 ž COP

bit 6 - 8 ž indicating Code which of the 7 registries it contains the address to add

bit 9 - 20 ž Address to add to the registry index.

If the registry is 0 then the indirizzamento every registry is diretto. Moreover index is constituted from 12 bit.

 

19) Which he is the main one I use of the registries index:

They concur the scansion of a carrier that GIVEN beginnings to the lease through istruzione the LOA DATI(1) indicating exactly to load the storage cell with the element with the carrier that it begins to the lease GIVEN and is found after n° of cells of spiazzamento a characterized respect to it from the R1 registry.

 

20) Describe operation JONR2 B(3):

If registry 2 contains a value < 0 it jumps to the instruction whose address is the sum of the part address of the cell characterized from the B label and of registry 3.

 

21) Describe the indiciato indirect indirizzamento:

It joins the characteristics of the indirect indirizzamento to the characteristics of the indiciato indirizzamento, in particular the preindiciato indirect indirizzamento and the postindiciato indirect indirizzamento are distinguished.

 

22) What is the meaning for preindiciato indirect indirizzamento:

The address of operating is found in the cell whose address is given from the sum of the Rxx registry and the field of the instruction.

 

23) What is the meaning for postindiciato indirect indirizzamento:

The address of operating is given from the sum of the Rxx registry with the address contained in the cell addressed from the field of the instruction.

 

24) What is the meaning for immediate indirizzamento:

The field of the instruction is a false indirizzamento in how much does not contain an address but operating same.

 

25) When one speaks about relative indirizzamenti you:

It is a type of indirizzamento that facilitates the operation of the operating system which it subdivides the memory in segments and it assigns to a data segment to a program, to this point all the addresses of the program will be shiftati up of an equal value to the address base of the segment.

 

26) How many types of relative indirizzamenti exist you:

There are 3 various types of relative indirizzamenti you which only differ for as the beginning of the segment, the indirizzamento based on the Program Counter, the registry base and the Registry comes chosen the base that is Gunlayer.

 

27) Describe the relative indirizzamento based on the Program Counter:

Operating finds to the lease sum of the spiazzamento and the Program Counter. The page that is the raggiungibili cells of memory are those that have to the center the cell where the instruction preceded therefore from half of the indirizzabili cells from the field of the instruction and the continuations from one same n° of cells is contained.

 

28) Describe the relative indirizzamento based on the Registry Base:

The registry base contains the address where it begins the segment, adding to it the present spiazzamento in the field of the instruction, obtains the address of operating.

 

29) Describe the relative indirizzamento based on the Registry Gunlayer:

It demands a modification del formed della instruction which it will contain the COP, the Registry Gunlayer and will indicate if leases must be added or be embezzled M al value del registry gunlayer in order to gain the address della operating.

 

30) Riassumere the set of instructions which it has the machine of Von Neumann:

Aritmetiche ADD ADDRxx

SUB SUBRxx

MUL

DIV

Salti JMP

JOP JOPRxx

JOZ JOZRxx

JON JONRxx

Trasferimenti From storage cell or registry to lease of memoria STO label STORxx label

STOAD label

From lease of memory to storage cell or registro LOA label LOARxx label

LOAN

LABS

From registry to accumulatore TAR

Scorrimenti SHRI

SHLE

Aim ciclo HLT