IBM Deskstar 120 GXP, Specifications

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DDMARDY- (Ultra DMA)
This signal is used only for Ultra DMA data transfers between the host and the device.
DDMARDY- is a flow control signal for Ultra DMA data out bursts. This signal is held
asserted by the device to indicate to the host that the device is ready to receive Ultra
DMA data out transfers. The device may negate DDMARDY- to pause an Ultra DMA data
out transfer.
DSTROBE (Ultra DMA)
This signal is used only for Ultra DMA data transfers between the host and the device.
DSTROBE is the data in strobe signal from the device for an Ultra DMA data in transfer.
Both the rising and falling edge of DSTROBE latch the data from DD(15:0) into the host.
The device may stop toggling DSTROBE to pause an Ultra DMA data in transfer.
Device Termination
The termination resistors on the device side are implemented on the drive side as follows:
!
33
Ω
for DD0 thru DD15, DMARQ, INTRQ
!
82
Ω
for CS0-, CS1-, DA0, DA1, DA2, DIOR-, DIOW-, DMACK-
!
22
Ω
for IORDY
6.1.3 Interface logic signal levels
The interface logic signal has the following electrical specifications:
0.5 V max. Output Low Voltage
2.4 V min. Output High Voltage Outputs
0.8 V max. Input Low Voltage
2.0 V min. Input High Voltage Inputs
Deskstar 120GXP hard disk drive specifications
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