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Difference between register variable and automatic variables?
Register variables are stored in register of microprocessor/micro-controller. The read/write access to register variable is the fastest because CPU never need any memory BUS operation to access these variable. Auto variable are stored in stack thus access are much slower. Auto variable can be converted to register by using register keyword before it. It has platform specific limitation. Register variable will work only if free registers are available to hold the variable for a function scope. In case of Microprocessor or microcontrollers having very less number of general purpose registers will never take register variable even if we declare it as register.
What is the difference between register and resister in elecronics?
A resistor reduces the flow of current between two terminals and thus reduces voltage. this is achieved through electrical resistance. All electrical conductors are resisters, some more resistant than others. The less resistance offered by a conductor, the easier it is for electricity to flow, thus the higher the current. Thus resisters allow circuit designers to control the flow of electricity. A register is a small unit of storage used by a digital processor. Computers typically have a relatively large array of working memory, however all the actual processing is done via a small set of registers. Registers work in much the same way as main memory, typically using a capacitor and transistor pair to denote each bit, however registers are significantly faster. Some registers are used for housekeeping purposes such as to keep track of the next instruction and for marking the top of the program stack, while other are used to provide input and output for the current instruction. In order for an instruction to process a value that value must first be moved to a register, typically one of the accumulator registers. If the instruction requires another operand, it must be moved to another register, typically a user register. After processing, the accumulator's value is moved back to main memory, either by the instruction itself or by a subsequent instruction.
What is the function of the instruction counter?
There is no such thing as an instruction counter. You are either referring to the instruction register (IR) or the program counter (PC), The PC is more commonly known as the instruction pointer (IP). The IR and IP work together. The IR fetches the instruction currently pointed to by the IP which is then incremented to refer to the next instruction. The IR is then decoded and executed and the cycle repeats ad infinitum (known as the fetch-decode-execute cycle). However, if the fetched instruction is a control transfer instruction (such as JMP), its execution will cause the IP to refer to another address which, in turn, causes execution to "branch" to a new section of code on the next fetch-decode-execute cycle. Note that a low-level JMP is equivalent to a goto statement in high-level code, however code can also branch through high-level if and switch statements as well as structured loops such as for, while and do-while statements.
How do you work my handheld game?
This question, cant' be answered, due to the fact we don't know what handheld game system you have. Please, read your instruction manual for help.
How does data travel around the processor?
InstructionsDefinitionStep 1: The original definition of a computer processor was any machine that could perform arithmetic and logic functions. Today a computer processor is usually defined as a microprocessor chip, or CPU, that executes commands and runs computer programs. One of the biggest manufacturers of microprocessors is the Intel Corporation. Typical computer programs that must be processed by CPUs include Internet browsers, word processors, and image manipulation software. Computer processors perform four basic functions to process data and run computer programs.FetchStep 1: Every instruction that a CPU processes is represented by a series of numbers. Once initiated, the numbers representing the requested action are stored in memory. The CPU then fetches or retrieves the instruction from program memory. A program counter, or PC, keeps track of the computer processor's location in the active program. If the memory is slow, the CPU may stall while waiting for the instruction to be returned.DecodeStep 1: The CPU then analyzes the instruction it fetched and decides how it should be processed. Typically a particular group of numbers in the instruction indicate which operation to perform, and in what sequence. In more advanced CPUs, a microprogram may also be used to help decode instructions for the computer processor. CPU microprograms can sometimes be modified (from the factory default) to change the way the processor translates instructions.ExecuteStep 1: Depending on the action required, the CPU then sends segments of the original instruction to the most appropriate section of the processor. For example, if additional actions are requested, an arithmetic logic unit (ALU) is attached to a group of inputs and outputs. The inputs provide the numbers to be processed, and the outputs contain the final sum or response to the request.WritebackStep 1: After executing the instruction, the processor writes the results back into memory. Sometimes the results are written to an internal register for quick access, while in other cases the results are written directly to the main memory. After the instruction has been executed and written to memory, the process repeats by fetching the next instruction value in the program counter. In more advanced computer processors, it is possible for multiple commands to be fetched, decoded, and executed simultaneously.http://www.answerbag.com/articles/How-Does-a-Computers-Processor-Work/3a8590f3-775a-16a0-900c-bd4f23f606a7
Why zero flag is not set in INX instruction of microprocessor 8085?
Because that is the way Intel designed the INX instruction of the 8085. The 8080 is also the same. INX increments (and DCX decrements) the 16 bit register pairs or BC, DE or HL, depending on what register pair you specify in the INX (or DCX) instruction. To check is the value is 0 after an INX (or DCX) instruction, you need to OR the values of the register pair into the A register. For example..... INX H ;increment HL register pair MOV A,H ; move H register into the accumulator ORA L ; Logical OR it with the L register JZ ADDR ; If 0 then jump to ADDR
How 8085 microprocessor got its name?
the previous CPU of Intel is 8080A. 8085 is the first CPU to work in 5volts. hence the name 8085 (8080+5)
What is the purpose of INSTRUCTION REGISTER in 8085 Microprocessor?
In 8085 general purpose registers are used to hold data like any other registers. In 8085 there are six types of special registers called general purpose registers. The general purpose registers in 8085 are B, C, D, E, H and L. Each register can hold 8 bit data. Apart from above functions these registers can also be used to work in pairs to hold 16 bit data. They can work in pairs such as B-C, D-E, H-L to store 16 bit data. The H-L pair work as a memory pointer. A memory pointer holds the address of a particular memory location. They can store 16 bit address as they work in pairs.
How does the microprocessor work?
Suppose we give a 8-bit instruction ADD B to the microprocessor then this instruction is not at all understood by microprocessor as it only accepts binary inputs so first of all it stores the instruction in the INSTRUCTION REGISTOR then it decodes this instruction ADD B to its suitable binary code 80H in the INSTRUCTION DECODER.. after converting to 80H then the microprocessor understands that .. yes i have to add the content of the resistor B with that of A(accumulator) and store the result in the accumulator A this is a small example how microprocessor operates facing the instructions
Draw a schemetic to demultiplex bus ad0-ad7 using any octal latch in 8085 microprocessor?
The 8085 microprocessor is used IC 74LS373 to latch the address of 8085. Basically latch is consists of 8 flip flops. Generally we used D-flip flops (Delay).The clock of these flip flops are connected together and available as a output pin called enable.Working : The address will appear on AD0 AD7 lines. The ALE will go high and forcingEnable = 1. This will make latch enable and ready to work. Before address disappears ALE = 0. This will make latch disable. AD0 - AD7 will now be used as data bus.Hence, AD0 - AD7 (low order) address bus of the 8085 microprocessor is multiplexed (time-shared) with the data bus. The buses need to be demultiplexed.
How does the Fetch Decode Execute work?
The program counter in the processor holds the address of the next instruction needed from main memory. The program counter copies its contents into the memory address register. The memory address register then sends the address along the address bus to main memory and the contents of the memory location specified by the address are sent along the data bus to the memory buffer register. The contents of the memory buffer register are then copied to the current instruction register where they are decoded and executed.
How does fetch decode cycle work?
The program counter in the processor holds the address of the next instruction needed from main memory. The program counter copies its contents into the memory address register. The memory address register then sends the address along the address bus to main memory and the contents of the memory location specified by the address are sent along the data bus to the memory buffer register. The contents of the memory buffer register are then copied to the current instruction register where they are decoded and executed.
How does fetch decode execute cycle work?
The program counter in the processor holds the address of the next instruction needed from main memory. The program counter copies its contents into the memory address register. The memory address register then sends the address along the address bus to main memory and the contents of the memory location specified by the address are sent along the data bus to the memory buffer register. The contents of the memory buffer register are then copied to the current instruction register where they are decoded and executed.
How does push work on registers and variables?
The PUSH instruction decrements the stack pointer by the size of the operand and then stores its operand at the memory address pointed to by the stack pointer. This leaves the stack pointer always pointing to the last element pushed onto the stack.The POP instruction reverses the sequence, retrieving the operand first, and then incrementing the stack pointer by the size of the operand.Also, PUSH and POP do not work on variables - they only work on register values. You can pop/push a variable, however, by using a register and then storing/retrieving the register to/from memory.
Can microprocessor work in freezers?
Yes they can.
What is the difference between the 8086 and the 8087?
The 8086 was a 16-bit microprocessor chip. It gave its name to the x86 architecture. It was the main CPU of the computer. The 8087 was the first math coprocessor for 16 bit processors. It was the first of the x87 architecture chips. it couldn't act as the main CPU in a computer, it was dedicated to doing floating point mathematical computations.
If there is no microprocessor in a computer or a device would it work?
no
