Response id (respid), Register: 0x4a (0xca) – LSI 53C810A User Manual

Page 133

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5-59

GEN bit in the

SCSI Interrupt Status One (SIST1)

register

is set. Refer to the table under

SCSI Timer Zero

(STIME0)

, bits [3:0], for the available time-out periods.

Note:

To reset a timer before it expires and obtain repeatable
delays, the time value must be written to zero first, and then
written back to the desired value. This is also required
when changing from one time value to another. See

Chapter 2, “Functional Description,”

for an explanation of

how interrupts are generated when the timers expire.

Register: 0x4A (0xCA)

Response ID (RESPID)
Read/Write

RESPID

Response ID

[7:0]

This register contains the IDs that the chip responds to
on the SCSI bus. Each bit represents one possible ID
with the most significant bit representing ID 7 and the
least significant bit representing ID 0. The

SCSI Chip ID

(SCID)

register still contains the chip ID used during

arbitration. The chip can respond to more than one ID
because more than one bit can be set in the

Response

ID (RESPID)

register. However, the chip can arbitrate

with only one ID value in the

SCSI Chip ID (SCID)

register.

7

0

ID

x

x

x

x

x

x

x

x

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