Emerson MVME147 Computer Hardware User Manual


 
CUSTOM SCSI PACKETS
2-26
2
3. During the message-in phase, the COMMAND COMPLETE message is
sent to the initiator.
4. The END OF TARGET SCRIPT code causes the firmware to disconnect
from the bus and return to you (through the vector provided in the
TARGET sequence packet) with a final status of $xx18, indicating the
TARGET script was completed successfully.
Example 2: Send (peripheral device type = processor devices):
CDB byte 0: $0A Command is a write
CDB byte 1: $20 The desired LUN is 1
CDB byte 2: $00 Allocation length MSB
CDB byte 3: $03 Allocation length
CDB byte 4: $00 Allocation length LSB
CDB byte 5: $00 Control byte=0: no link, no flag
Target script for example 2:
DC.B $08 DATA OUT PHASE
DC.B $10 STATUS PHASE
DC.B $18 MESSAGE IN PHASE
DC.B $1C END OF TARGET SCRIPT
1. During the data-out phase, the initiator writes data to the MVME147. The
byte count is $300.
2. During the status phase, the GOOD status is sent.
3. During the message-in phase, the COMMAND COMPLETE message is
sent.
4. The end of TARGET script code causes the firmware to disconnect from
the SCSI bus and return to you through the vector provided in the
TARGET sequence packet.
WORDS $08 and $0A:
COMMAND TABLE POINTER -- The address of the
TARGET role command table. Below is a description of the
requirements of the TARGET command table.
TARGET COMMAND TABLE DESCRIPTION:
CT word 00: (Byte 0 -- status/flag byte.)
Bit assignments: