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Avago Technologies LSI53C896 User Manual

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SCSI Registers

4-47

Version 3.3

Copyright © 1998–2003 by LSI Logic Corporation. All rights reserved.

SDP0L

Latched SCSI Parity

3

This bit reflects the SCSI parity signal (SDP0/),
corresponding to the data latched in the

SCSI Input Data Latch (SIDL)

. It changes when a new

byte is latched into the least significant byte of the SIDL
register. This bit is active HIGH, in other words, it is set
when the parity signal is active.

MSG

SCSI MSG/ Signal

2

C_D

SCSI C_D/ Signal

1

I/O

SCSI I_O/ Signal

0

These SCSI phase status bits are latched on the
asserting edge of SREQ/ when operating in either the
initiator or target mode. These bits are set when the
corresponding signal is active. They are useful when
operating in the low level mode.

1

0

1

0

1

21

1

0

1

1

0

22

1

0

1

1

1

23

1

1

0

0

0

24

1

1

0

0

1

25

1

1

0

1

0

26

1

1

0

1

1

27

1

1

1

0

0

28

1

1

1

0

1

29

1

1

1

1

0

30

1

1

1

1

1

31

Table 4.6

SCSI Synchronous Data FIFO Word Count

FF4

(SSTAT2 Bit 4)

FF3

FF2

FF1

FF0

Bytes or

Words in the

SCSI FIFO