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Avago Technologies LSI53C876E User Manual

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SCSI Registers

4-47

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)

register. 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 three SCSI phase status bits (MSG, C_D, and
I_O) are latched on the asserting edge of SREQ/ when
operating in either initiator or target mode. These bits are
set when the corresponding signal is active. They are
useful when operating in low level mode.

0

1

0

1

0

10

0

1

0

1

1

11

0

1

1

0

0

12

0

1

1

0

1

13

0

1

1

1

0

14

0

1

1

1

1

15

1

0

0

0

0

16

Table 4.6

SCSI Synchronous Data FIFO Word
Count (Cont.)

FF4

(SSTAT2 bit 4)

FF3

FF2

FF1

FF0

Bytes or

Words in

the SCSI

FIFO