(DMA) A method of moving data from a storage device to RAM.
A method of fast data transfer between the peripherals and the computer memory. The transfer does not involve the CPU.
Specialized circuitry or a dedicated microprocessor that transfers data from memory to memory without using the CPU.
A technique where information is transferred in a computer with the assistance of the microprocessor. For example, it's possible to transfer information between memory and an "intelligent" device, such as a hard drive, by simply telling a DMA chip to" move this data from memory here to disk driver there." The information is moved without slowing down the microprocessor.
A method of transferring information directly from a mass-storage device such as a hard disk or from an adapter card in memory (or vice versa), without the information passing through the processor. because the processor is not involved in the transfer, direct memory access is usually very fast. DMA transfers are controlled by a special chip known as a DMA controller; 8237A is used in most PCs. Generally, most PCs use two of these chips to provide 8 DMA channels numbered 0 through 7; channel 4 is used to connect-or cascade-the two controllers together. Channels 0 thru- 3 are 8-bit channels, and can manage up to 64K of data in a single DMA operation; channels 5 thru 7 transfer data 16 bits at a time and can manage up to 128K of data. Channel 3 is reserved for the floppy disk drive controller, and channel 5 is used by the hard-disk controller in PS/2 systems.
A fast way of transferring data within (and sometimes between) computers. For example, DMA is often used to read data from a LAN adapter board and write it into a PC's memory (and vice versa). A DMA controller (often on a PC's motherboard) seizes the bus periodically (for example, once for every 16-bit transfer) to read data from the adapter, then seizes it again to write it to memory (therefore requiring two bus cycles per transfer).
A method of moving data from a storage device directly to RAM, without using the CPU's resources.
A procedure or method defined for gaining direct access to main storage and achieving data transfers without involving the processor.
the ability of an I/O subsystem to transfer data to and from memory subsystem without processor intervention
a particular method of getting information from memory, usually large blocks of memory by addressing it directly rather than through normal buffers
A process for transferring data directly to and from main memory, without passing through the CPU. DMA improves speed and efficiency by allowing the system to continue CPU processing even while it is transferring data to/from the hard drive.
A method for hardware to send instructions to the computer. Like IRQ, limited in number, and only device can be allocated to each DMA channel. Plug and Play alleviates concerns about configuring DMA channels.
(DMA) (n.) The transfer of data directly into memory without supervision of the processor. The data is passed on the bus directly between the memory and another device. Contrast with direct virtual memory access (DVMA).
In normal circumstances, when we load a file, data is transferred from a disk to the processor and then from the processor to RAM. Some computers are able to transfer data directly from a storage device such as a disk drive straight into RAM. This feature, called DMA, speeds up the computer since the processor is not required to participate in transferring data and is free to do other processing.
A facility used on the PC architecture which allows for a peripheral to read or write from main memory without the help of the CPU. PCI peripherals use bus mastering and do not need DMA. DNS
The ability of a device to access system memory without having the CPU prefetch and send it the information.
A quick method of moving data from a storage device directly to RAM, which speeds processing.
A facility that permits I/O transfers directly into or out of memory without passing through the processor's general registers; performed either independently of the processor or on a cycle-stealing basis.
The fastest method of data transfer available for multitasking operating systems. Data is transferred from SCSI devices to system memory (RAM) via the SCSI card without using the system?s CPU.
Technology that enables certain devices, such as hard disks and CD or DVD drives, to transfer information directly to and from the computer's memory without using the computer's processor. DMA improves the performance of the device and frees the computer's processor so it can perform other tasks.
allowing devices on a bus to access memory without interfering with the CPU.
When a device reads or writes in memory, asynchronously and without specific intervention by a CPU. In order to perform DMA, the device or its attachment must have some means of storing a memory address and incrementing it, usually through mapping registers. The device writes to physical memory and in so doing can invalidate cache memory bus-watching cache compensates.
Allows a 64KByte block of memory to be set aside for high-speed transfer of data to PC system memory. Boards which support single DMA access can store up to 64KBytes of data (32K samples) at speeds which can reach 250KBytes per second on ISA-bus PCs. Dual DMA access means that a second 64KByte block is set up while the first is being filled, allowing unlimited sample sizes.
Direct memory access (DMA) describes the ability of a device to directly access (read from and write to) CPU memory, without CPU intervention.
Direct Memory Access provides a way to transfer data between devices and memory at very high speeds.
This term refers to the movement of data directly from memory to some other device, such as the disk drive, without first being loaded in the microprocessor.
A technique for transferring data directly between two peripherals (usually memory and an I/O device) with only minimal intervention by the processor. Abbreviated DMA. DMA transfers are managed by a third device called a DMA controller, which shares the memory bus with the processor. Unused memory cycles are stolen by the DMA controller. The processor is only involved, via an interrupt, once the entire block of data has been transferred. In that way, the processor is freed to do other things and overall throughput is increased.
Memory access that does not involve the microprocessor. DMA is frequently used for data transfer directly between memory and a peripheral device such as a disk drive. See also: hardware configuration
Direct memory access (DMA) is a feature of modern computers, that allows certain hardware subsystems within the computer to access system memory for reading and/or writing independently of the central processing unit. Many hardware systems use DMA including disk drive controllers, graphics cards, network cards, and sound cards. Computers that have DMA channels can transfer data to and from devices with much less CPU overhead than computers without a DMA channel.