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Table 5.5 scsi phase comparisons, Scsi phase comparisons, Table 5.5 – Avago Technologies LSI53C895A User Manual

Page 251

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Transfer Control Instructions

5-29

valid when the LSI53C895A is operating in Initiator mode.
Clear these bits when the LSI53C895A is operating in
Target mode.

RA

Relative Addressing Mode

23

When this bit is set, the 24-bit signed value in the

DMA

SCRIPTS Pointer Save (DSPS)

register is used as a

relative offset from the current DMA SCRIPTS Pointer
(DSP) address (which is pointing to the next instruction,
not the one currently executing). The relative mode does
not apply to Return and Interrupt SCRIPTS.

Jump/Call an Absolute Address

Start execution at the new absolute address.

Jump/Call a Relative Address

Start execution at the current address plus (or minus) the
relative offset.

Table 5.5

SCSI Phase Comparisons

MSG

C/D

I/O

SCSI Phase

0

0

0

Data-Out

0

0

1

Data-In

0

1

0

Command

0

1

1

Status

1

0

0

Reserved

1

0

1

Reserved

1

1

0

Message-Out

1

1

1

Message-In

Command

Condition Codes

Absolute Alternate Address

Command

Condition Codes

Don’t Care

Alternate Jump Offset