UDMA: Difference between revisions
Jump to navigation
Jump to search
imported>Mikhail Ryazanov m MOS:CAPS, fmt. |
imported>Elmepi image+ |
||
| Line 8: | Line 8: | ||
Modes faster than UDMA mode 2 require an 80-conductor cable to reduce data [[settling time]]s, lower [[electrical impedance|impedance]] and reduce [[crosstalk]].<ref>[https://archive.org/stream/SCSISpecificationDocumentsATAATAPI/ATA_ATAPI/AT%20Attachment%20with%20Packet%20Interface%20-%207%20Volume%202%20-%20Parallel%20Transport%20Protocols%20and%20Physical%20Interconnect%20%28ATA_ATAPI-7%20V2%29%20Revision%204b#page/n189/mode/2up AT Attachment with Packet Interface - 7 Volume 2 - Parallel Transport Protocols and Physical Interconnect (ATA/ATAPI-7 V2) E.2.1.1 Cabling p172]</ref> | Modes faster than UDMA mode 2 require an 80-conductor cable to reduce data [[settling time]]s, lower [[electrical impedance|impedance]] and reduce [[crosstalk]].<ref>[https://archive.org/stream/SCSISpecificationDocumentsATAATAPI/ATA_ATAPI/AT%20Attachment%20with%20Packet%20Interface%20-%207%20Volume%202%20-%20Parallel%20Transport%20Protocols%20and%20Physical%20Interconnect%20%28ATA_ATAPI-7%20V2%29%20Revision%204b#page/n189/mode/2up AT Attachment with Packet Interface - 7 Volume 2 - Parallel Transport Protocols and Physical Interconnect (ATA/ATAPI-7 V2) E.2.1.1 Cabling p172]</ref> | ||
[[File:SANDISK Extreme Pro CompactFlash card 32 GB 90 MBs.jpg|thumb|[[SanDisk]] 32 GB [[CompactFlash|CF]] card supporting [[CompactFlash#Video Performance Guarantee|VPG20]] and UDMA7]] | |||
{| class="wikitable" style="text-align:center" | {| class="wikitable" style="text-align:center" | ||
|+ Transfer modes | |+ Transfer modes | ||
Latest revision as of 19:12, 3 October 2025
Template:Short description Script error: No such module "For". Template:Refimprove
The Ultra DMA (Ultra Direct Memory Access, UDMA) modes are the fastest methods used to transfer data through the ATA hard disk interface, usually between a computer and an ATA device. UDMA succeeded Single/Multiword DMA as the interface of choice between ATA devices and the computer. There are eight different UDMA modes, ranging from 0 to 6 for ATA (0 to 7 for CompactFlash), each with its own timing.
Modes faster than UDMA mode 2 require an 80-conductor cable to reduce data settling times, lower impedance and reduce crosstalk.[1]
| Mode | Number | Also called | Maximum transfer rate (MB/s) |
Minimum cycle time |
Defining standard |
|---|---|---|---|---|---|
| Ultra DMA | 0 | 16.7 | 120 ns | ATA-4 | |
| 1 | 25.0 | 80 ns | ATA-4 | ||
| 2 | Ultra ATA/33 | 33.3 | 60 ns | ATA-4 | |
| 3[2] | 44.4 | 45 ns | ATA-5 | ||
| 4[2] | Ultra ATA/66 | 66.7 | 30 ns | ATA-5 | |
| 5[2] | Ultra ATA/100 | 100 | 20 ns | ATA-6 | |
| 6[2] | Ultra ATA/133 | 133 | 15 ns | ATA-7 | |
| 7 | Template:Nobr | 167 | 12 ns | CompactFlash 6.0[3] |
See also
- PIO—The first interface type used between devices (mainly hard disks) and the computer.
- Parallel ATA
- Serial ATA