DMA transfer mode
The direct memory access or DMA mode of data transfer is the fastest amongst all the modes of data transfer.In this mode ,the device may transfer data directly to/from memory without any interference from the CPU.The device requests the CPU through a DMA controller to hold its data,address and control bus so that the device may transfer data directly to/from memory.
DMA
DMA (direct memory access) transfer mode or PIO (programmed input/output) transfer mode
ECP is faster (because it uses a DMA channel).
DMA (Direct Memory Access) allows devices to transfer data directly to and from memory without involving the CPU. UDMA (Ultra DMA) is an improvement over DMA that increases data transfer speeds by using faster transfer modes and protocols.
The normal operation to move data in a computer system is via the processor but many bulk transfer devices use "direct memory access" or "DMA". The transfer process uses data buses to move data from one peripheral to another without loading the data into the processor. Not only is this a faster way to move large amounts of data it also frees the processor to carry out other tasks. DMA is generally performed under the supervision of the processor even though the processor is not directly involved in the operation.
The DMA controller can be used to steal memory cycles from the processor. Hence this interweaing technique is called cycle stealing The DMA Controller may be Given exclusive access main memory to transfer the block of data without interruption this is known as block or burst mode
DMA is faster it has 7 modes when PIO only goes up 4 modes
PIO
PIO
No, IDE stands for Integrated Drive Electronics A hardware interface widely used to connect hard disks, optical discs and tape drives to a PC. Introduced in 1986 with 20MB of storage, capacities increased a thousandfold in less than two decades. Compared to the SCSI interface, IDE has been the more economical choice. (Direct Memory Access) Specialized circuitry or a dedicated microprocessor that transfers data from memory to memory without using the CPU. Although DMA may periodically steal cycles from the CPU, data are transferred much faster than using the CPU for every byte of transfer. On PCs, there are eight DMA channels commonly used as follows. Most sound cards are set to use DMA channel 1. See PIO mode. DMA Used for 0 8-bit transfer 1 8-bit transfer 2 Floppy disk controller 3 8-bit transfer 4 Cascaded from 0-3 5 16-bit transfer 6 16-bit transfer 7 16-bit transfer DMA Disk Transfers There are various modes of data transfer on IDE disk drives. The PIO modes use the CPU, and the DMA modes bypass the CPU.