Register: 0x06

SCSI Destination ID (SDID)

Read/Write

7

 

 

 

 

 

 

 

4

 

 

 

 

3

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

R

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ENC

 

 

 

 

 

 

 

x

x

 

 

x

 

 

 

 

x

 

 

 

 

0

 

0

 

 

 

0

 

 

 

0

 

 

R

 

Reserved

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[7:4]

ENC

 

Encoded Destination SCSI ID

 

 

 

 

 

 

 

 

[3:0]

 

 

Writing these bits set the SCSI ID of the intended initiator

 

 

or target during SCSI reselection or selection phases,

 

 

respectively. When executing SCRIPTS, the SCRIPTS

 

 

processor writes the destination SCSI ID to this register.

 

 

The SCSI ID is defined by the user in a SCRIPTS Select

 

 

or Reselect instruction. The value written is the

 

 

 

 

 

 

binary-encoded ID. The priority of the 16 possible IDs, in

 

 

descending order, is:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Highest

 

 

 

 

 

 

 

 

Lowest

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

7

 

6

5

 

4

 

3

 

2

1

0

 

15

14

13

 

12

11

10

9

 

8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Register: 0x07

General Purpose (GPREG0)

Read/Write

7

 

5

4

 

 

 

0

 

R

 

 

 

GPIO

 

 

x

x

x

0

x

x

x

x

 

 

 

 

 

 

 

 

Reads to this register will always yield the same values. A write to this register will cause the data written to be output to the appropriate GPIO pin if it is set to the output mode in the General Purpose Pin Control Zero (GPCNTL0) register.

R

Reserved

[7:5]

GPIO

General Purpose I/O

[4:0]

These bits are programmed through the General Purpose Pin Control Zero (GPCNTL0) register as inputs, outputs, or to perform special functions. As an output, these pins can be used to enable or disable external terminators. It

SCSI Registers

4-35

Page 127
Image 127
LSI 53C875A Scsi Destination ID Sdid Read/Write, Encoded Destination Scsi ID, General Purpose GPREG0 Read/Write, Gpio