Byte Description Bit1 Interrupt Channel Bit 7 Reserved (0)Bit 6 Interrupt channel 15Bit 5 Interrupt channel 14Bit 4 Reserved (0)Bit 3 Interrupt channel 12Bit 2 Interrupt channel 11Bit 1 Interrupt channel 10Bit 0 Interrupt channel 9Byte 2 SCSI Identifier Bits 7-3 Reserved (0)Bits 2-0 Binary value of SCSIIdentifierAfter completing this command, HACC will be set indicating normal completion.Enable Target Mode Command (Operation Code 0C)A special host adapter command (0C) enables and disables target mode. The hostadapter requires that two bytes of outbound information follow the command byte.The information bytes contain the following information:Byte 0 Enable/Disable Target Mode: This parameter specifies which operatingmodes the host adapter will use. If the byte is set to 00h, theAHA-1740A/1742A/1744 will operate only in Initiator Mode. If thebyte is set to 01h, the host adapter will operate both as an initiatorand as a processor-type target SCSI device. Any other value is invalid.The default value after a Hard Reset, Soft Reset, or Power-On Resetis 00h (Initiator only).Byte 1 Logical Unit Mask: This parameter byte contains an 8-bit maskindicating the Logical Units which will respond in Target Mode. Bit 7corresponds to LU 7, and so forth. If the bit is one, the correspondingLU will be treated as installed. If the bit is zero, the LU will be treatedas not installed.If the AHA-1740A/1742A/1744 does not have the Target Mode feature installed, thehost adapter will indicate an invalid host adapter command. If an attempt is made tochange from target mode while there are still target mode CCBs being processed bythe host adapter, the host adapter will post an invalid host adapter commandindication.If the command disables Target Mode, the Logical Unit Mask byte will be ignored. Ifthe command enables Target Mode, the Logical Unit Mask byte must contain at leastone bit, indicating the presence of at least one Logical Unit.The SCSI Inquiry command will provide an indication to other initiators that theLogical Unit is installed or not installed in byte 1 of the returned inquiry data.EISA-to-Fast SCSI Host Adapter Standard Mode Firmware Description5-9
