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

7

0

ID

x

x

x

x

x

x

x

x

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.

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LSI 53C810A technical manual Register 0x4A 0xCA, Response ID Respid Read/Write Respid Response ID70