PocketPC - IDE harddrive

[Szoke Szilard-Zsigmond]

> Regen is DMA-ztak a winchesterek, vagy csak az UDMA-33 ota?
A DMA-t eleg reg hasznaljak, egyes doksik szerint (most nem talalom)
van/volt Single-Word DMA is (ez nem adott szamottevo
sebessegnovekedest), van Multi-Word DMA (ez mar sokat javitott) es van
UDMA. Egy becsuletes nem UDMA-s HDD is tud MDMA-t.

Ha erdekel bovebb info, nezd meg ezeket a linkeket:
http://www.faqs.org/faqs/pc-hardware-faq/enhanced-IDE/part1/
http://thef-nym.sci.kun.nl/cgi-pieterh/atazip/atafq.html

Ha nincs kedved utananezni, egyeb forrasokbol itt van ket tablazat:

Forras 1:

ATA    Protocol      DMA Mode   Burst Speed
----------------------------------------------
ATA    IDE           PIO-0      3.3 - 8.3 MB/s
                             PIO-1
                             PIO-2
                             MDMA-0

ATA-2  Fast ATA      PIO-3      11.1 - 13.3 MB/s
               (EIDE)        MDMA-1

ATA-3  Fast ATA      PIO-4      16.6 MB/s
               (EIDE)        MDMA-2
                                 UDMA-0

ATA-4  UltraATA-33   UDMA-2     33.3 MB/s

ATA-5  UltraATA-66   UDMA-4     66.6 MB/s

ATA-6  UltraATA-100  UDMA-5     100 MB/s

ATA-7  UltraATA-133  UDMA-6     133 MB/s



Forras 2:

BTW, there is nothing "magical" about UltraDMA over PIO or multiword
DMA -- except for the fact that UltraDMA does a CRC -- which helps
preserve data integrity. Before UltraDMA, IDE/ATA DMA wasn't as
reliabile as SCSI DMA. Here is the list of IDE/ATA speeds:

Programmed I/O (PIO -- eats CPU usage):
  Mode 0 (Original IDE) 3MBps
  Mode 1 5MBps
  Mode 2 8MBps
  Mode 3 11MBps
  Mode 4 (common before UDMA) 16MBps
  Mode 5 (Rarely Supported) 22MBps

Multiword Direct Memory Access (MDMA, no CRC checking):
  Mode 0 8MBps
  Mode 1 11MBps
  Mode 2 (common before UDMA) 16MBps

UltraDMA (UDMA, DDR signaling, CRC checking):
  Mode 0 16MBps
  Mode 1 25MBps
  Mode 2 (Ultra33) 33MBps
  Mode 3 (80pin) 50MBps
  Mode 4 (Ultra66, 80pin) 66MBps
  Mode 5 (Ultra100, 80pin) 100MBps


    Udv
        Szilard