IBM DBCA-203240, Технические характеристики

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AAH Enable read look-ahead feature
BBH 4 bytes of ECC apply on Read Long/Write Long commands
CCH Enable reverting to power on defaults
Warning 1. Hard reset or power off must not be done in 5 seconds after write
command completion when write cache is enabled.
Note 1.
When Feature register is 03h ( = S e t Transfer mode), the Sector Count Register specifies the transfer mech-
anism. The upper 5 bits define the type of transfer and the low order 3 bits encode the mode value.
PIO Default Transfer Mode 00000 000
PIO Default Transfer Mode,Disable IORDY 00000 001
PIO Flow Control Transfer Mode x 00001 nnn (nnn=000,001,010,011,100)
Single word DMA mode x 00010 nnn (nnn=000,001,010)
Multiword DMA mode x 00100 nnn (nnn=000,001,010)
Ultra DMA mode x 01000 nnn (nnn=000,001,010)
Note 2.
When Feature register is 05h ( = E n a b l e Advanced Power Management), the Sector Count Register specifies
the Advanced Power Management level.
C0h - FEh ... The deepest Power Saving mode is Active Idle
80h - BFh ... The deepest Power Saving mode is Low power Idle
01h - 7Fh ... The deepest Power Saving mode is Standby
00h,
FFh ...Aborted
When Feature register is 85h (=Disable Advanced Power Management), the deepest Power Saving mode
becomes Active Idle.
Note 3.
If the number of auto reassigned sectors reaches the device's reassignment capacity, the write cache function
will be automatically disabled. Although the device still accepts the Set Features command (with Feature
register = 02h) without error, the write cache function will remain disabled. For current write cache func-
tion status, please refer to the Identify Device Information(129word) by Identify Device command.
Note 4.
After power on reset or hard reset, the device is set to the following features as default.
Write cache : Enable
ECC bytes : 4 bytes
Read look-ahead : Enable
Reverting to power on defaults : Disable
Address Offset mode : Disable
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O E M Specifications of DBCA-2xxxxx 2.5 inch H D D