User`s manual

siop_key Error Codes

SBCSCSI/D1 D-7

SI_BERRCMD (0x0F)

This status if returned if a bus error occurs when the SIOP is attempting to

access the local bus while it is physically threaded to a SCSI device in any

phase other than a SCSI bus DATA PHASE (i.e., BERR while sending a CDB

out to a target). The Firmware gets the target device off the SCSI bus before

returning this error code. The err_addr field of the siop_struc points to the fault

address.

SI_ILGLINST (0x10)

This interrupt is generated when the SIOP attempts to execute an illegal

SCRIPTS instruction. Several different situations can produce an illegal

SCRIPTS instruction; however, each is fatal and no attempt to retry the

command should be made. The Firmware gets the current target off the SCSI

bus before terminating the command and returning status to the user. The

err_addr field of the siop_struc points to the address where the illegal

instruction is located.

Some of the sources of an illegal instruction are:

1. The NCR SCRIPTS compiler generated the wrong opcode for a SCRIPTS

instruction forcing the SIOP to execute an illegal opcode.

2. The memory where the SCRIPTS reside has been overwritten or otherwise

corrupted resulting in the SIOP executing an illegal opcode.

3. The SIOP attempts to execute a SCRIPTS instruction that is non-longword

(four-byte) aligned. All SCRIPTS must be aligned to byte boundaries that

are integer multiples of 4.

SI_UDC (0x11)

This error code is returned when a target unexpectedly transitions to the bus

free state. This condition may be caused by a problem with the target or on the

SCSI bus itself.

The user should retry this command at least once in an attempt to recover from

some random or transient problem with the target.