Tandberg Data
Hardware Interface
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Tandberg SLR Reference Manual
8-13
The Data In Phase allows data to be transferred from the Target to the
Initiator in the following way:
The Target asserts I/O.
p
For each byte, the Tar-
get asserts REQ.
{
The Initiator reads the
byte and asserts ACK.
The Target releases the
data bus and deasserts
REQ, whereupon the
Initiator deasserts ACK.
-BSY
-SEL
-ATN
-MSG
-C/D
-I/O
-REQ
-ACK
First Data In
Last Data In
min. 400 ns
min. 55 ns
min. 0 ns
min. 0 ns
-DB(0-7, P)
DB(8-15, P1)
Figure 8.7 Data In Sequence
This completes the byte transfer. This cycle is repeated until the last data byte has been
transferred.
8.4.8. Status Phase
The Status Phase is entered when the Drive has completed a command execution, or if a
non-recoverable error has occurred. In this phase BSY, C/D and I/O will be asserted and SEL
and MSG deasserted. After a bus settle delay of at least 400 ns, the Drive puts the status
byte on the bus and asserts REQ. The Initiator should read the byte and assert ACK. This
causes the Target to deassert REQ, whereupon the Initiator can deassert ACK.