In 125 words describe the steps to active listening.

shusha [124]

Answer:

Direct memory access (DMA) is a process that allows an input/output (I/O) device to send or receive data directly to or from the main memory, bypassing the CPU to speed up memory operations and this process is managed by a chip known as a DMA controller (DMAC).

Explanation:

A defined portion of memory is used to send data directly from a peripheral to the motherboard without involving the microprocessor, so that the process does not interfere with overall computer operation.

In older computers, four DMA channels were numbered 0, 1, 2 and 3. When the 16-bit industry standard architecture (ISA) expansion bus was introduced, channels 5, 6 and 7 were added.

ISA was a computer bus standard for IBM-compatible computers, allowing a device to initiate transactions (bus mastering) at a quicker speed. The ISA DMA controller has 8 DMA channels, each one of which associated with a 16-bit address and count registers.

ISA has since been replaced by accelerated graphics port (AGP) and peripheral component interconnect (PCI) expansion cards, which are much faster. Each DMA transfers approximately 2 MB of data per second.

A computer's system resource tools are used for communication between hardware and software. The four types of system resources are:

I/O addresses
Memory addresses.
Interrupt request numbers (IRQ).
Direct memory access (DMA) channels.

DMA channels are used to communicate data between the peripheral device and the system memory. All four system resources rely on certain lines on a bus. Some lines on the bus are used for IRQs, some for addresses (the I/O addresses and the memory address) and some for DMA channels.

A DMA channel enables a device to transfer data without exposing the CPU to a work overload. Without the DMA channels, the CPU copies every piece of data using a peripheral bus from the I/O device. Using a peripheral bus occupies the CPU during the read/write process and does not allow other work to be performed until the operation is completed.

With DMA, the CPU can process other tasks while data transfer is being performed. The transfer of data is first initiated by the CPU. The data block can be transferred to and from memory by the DMAC in three ways.

In burst mode, the system bus is released only after the data transfer is completed. In cycle stealing mode, during the transfer of data between the DMA channel and I/O device, the system bus is relinquished for a few clock cycles so that the CPU can perform other tasks. When the data transfer is complete, the CPU receives an interrupt request from the DMA controller. In transparent mode, the DMAC can take charge of the system bus only when it is not required by the processor.

However, using a DMA controller might cause cache coherency problems. The data stored in RAM accessed by the DMA controller may not be updated with the correct cache data if the CPU is using external memory.

Solutions include flushing cache lines before starting outgoing DMA transfers, or performing a cache invalidation on incoming DMA transfers when external writes are signaled to the cache controller.

4 0

2 years ago

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"Write a program that calculates the balance of a savings account at the end of a period of time. It should ask the user for the

Akimi4 [234]

Answer:

#include <iostream>

#include <fstream>

using namespace std;

int main() {

// Definitions

double annualInterest; // The annual interest rate

double balance; // The account balance

int months; // Total number of months

double totalDeposit = 0.0; // Total deposited value

double totalWithdraw = 0.0; // Total withdrawn value

double earnedInterest= 0.0; // The earned amount

double deposited; // Monthly deposited value

double withdrawn; // Monthly withdrawn value

// Get the initial required data.

cout<<"Please enter the annual interest rate,\n";

cout<<" Interest rate: ";

cin >>annualInterest;

cout<<"--------------------------------------------\n";

cout<<"Please enter the starting balance,\n";

do{

cout<<"[the number could not be negative]\n";

cout<<"Starting Balance: ";

cin >>balance;

}while(balance<0);

cout<<"--------------------------------------------\n";

cout<<"Please enter the number of months,\n";

do{

cout<<"[the number could not be less than 0]\n";

cout<<"Number of months: ";

cin >>months;

}while(months<0);

// Iterated Loop to get all the months data.

for(int month=1; month <= months; month++){

// Get the deposited value during that month.

cout<<"Enter the deposited value during month "

<<month<<",\n";

do{

cout<<"[the value could not be less than 0]\n";

cout<<" Deposited value: ";

cin >>deposited;

}while(deposited<0);

totalDeposit += deposited;

balance += deposited;

// Get the withdrawn value during that month.

cout<<"Enter the withdrawn value during month "

<<month<<",\n";

do{

cout<<"[the value could not be less than 0]\n";

cout<<" Withdrawn value: ";

cin >>withdrawn;

}while(withdrawn<0);

totalWithdraw += withdrawn;

balance -= withdrawn;

// Negative balance close the program.

if(balance < 0){

cout<<"Sorry, the account has been closed due to\n";

cout<<"the negative balance.\n";

break;

// Calculate value due to the interest rate.

}

else {

earnedInterest += (annualInterest/12) * balance;

// monthly interest rate

balance += (annualInterest/12) * balance;

}

// Display the statistics,

ofstream file;

file.open ("Report written to Report.txt");

file << "Report written to Report.txt\n";

file.close();

cout<<"The ending balance: "<<balance<<std::endl;

cout<<" Total deposited: "<< totalDeposit<<std::endl;

cout<<" Total withdrawals: "<< totalWithdraw<<std::endl;

cout<<" Earned interest: "<< earnedInterest<<std::endl;

cout<<"============================================\n";

return 0;

}

6 0

2 years ago

What is the missing part to have the output as 3 2 1 while count >0 : print(count) count -= 1

Natali [406]

Answer:

Explanation:

16

6 0

2 years ago

If involved in a boating accident causing serious bodily injury or death while boating under the influence, the operator has com

9966 [12]

Answer:

felony

Explanation:

It is an offence on the part of a boat operator who is under the control of alcohol while boating, as such could result in property damage, serious bodily injury or death. Where such leads to bodily injury or deaths, the operator could be convicted for felony while misdemeanor applies to property damage.

There have been a reoccurring boating incidence in the country especially in the state of Florida, which has the highest number of boating fatalities hence created stiff penalties for boating under the influence of alcohol.

While it is adviseable for motorists not to drink and drive, it is also not lawful be under the influence when boating as such could cause injury, deaths or property damage and such operator would receive appropriate penalty depending on the outcome of the incident.

6 0

2 years ago

When would it be necessary to edit the information shown on an electronic business card?

Goryan [66]

Answer:

Really depends on your situation. If you specified, I'd have an asnwer

3 0

2 years ago

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