IBM DBCA-203240, Specifications

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STOP (Ultra DMA)
This signal is used only for Ultra D M A data transfers between host and drive.
STOP shall be asserted by the host prior to initiation of an Ultra D M A burst. STOP shall
be negated by the host before data is transferred in an Ultra D M A burst. Assertion of STOP
by the host during or after data transfer in an Ultra D M A mode signals the termination of
the burst.
-DDMARDY (Ultra DMA)
This signal is used only for Ultra D M A data transfers between host and drive.
- D D M A R D Y is a flow control signal for Ultra D M A data out bursts. This signal is held
asserted by the device to indicate to the host that the device is ready to receive Ultra D M A
data out transfers. The device may negate - D D M A R D Y to pause an Uptra D M A data out
transfer.
DSTROBE (Ultra DMA)
This signal is used only for Ultra D M A data transfers between host and drive.
DSTROBE is the data int strobe signal from the device for an Ultra D M A 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 D M A data in transfer.
6.3 Interface Logic Signal Levels
The interface logic signal have the following electrical specifications:
I n p u t s : I n p u t H i g h V o l t a g e
Ä
2 . 0 V m i n . / V c c + 0 . 7 V m a x .
I n p u t L o w V o l t a g e
Ä Ä
0 . 5 V m i n . / 0 . 8 V m a x .
O u t p u t s : O u t p u t H i g h V o l t a g e
Ä
2 . 4 V m i n .
O u t p u t L o w V o l t a g e
Ä
0 . 5 V m a x .
C u r r e n t : D r i v e r S i n k C u r r e n t
Ä
2 4 m A m i n .
D r i v e r S o u r c e C u r r e n t
Ä Ä
4 0 0 u A m i n .
Electrical Interface Specifications
37