IBM T400F manual Setting the Loop ID to Provide Status About the Loop

Setting the Loop ID to Provide Status About the Loop

If Feature Switch 3 on the Ultrium 2 Tape Drive is set to OFF (see		in Figure 6),
the LID/status connector	has the following definition:

vPins 1, 2, 3, 4, 7, and 8 are inputs and are used to set the LID.

vPins 5 and 6 are used as outputs:

–Pin 5 has three states: off (ground), on (3.3 V), and alternating (between off and on). Pin 5 will be off if the drive does not detect light on the Fibre Channel connector, if (while communicating as an L_port) the drive does not complete the Loop Initialization Protocol (LIP), or if (while communicating as an N_port) the drive does not complete logging in to the host or switch. Pin 5 will be on if the drive detects light, successfully completes the LIP process, or logs in to another port. After the drive has completed the LIP process, the pin will be alternating when the drive is receiving SCSI commands, and the pin will be on when the drive is not receiving SCSI commands.

–Pin 6 indicates that the drive detects light. If pin 6 is on but pin 5 is off, this could indicate communication problems across the fiber cable.

–If the drive is installed in an enclosure, pins 5 and 6 may be used to support external indicators, such as light-emitting diodes (LEDs), on the enclosure.

Note: If indicators are used on an enclosure, the drive does not report error codes 8 and F (Fibre Channel problems) to the single-character display. Instead, pins 5 and 6 signal to the indicators that there is a problem.

vPin 9 is ground.

Figure 6. Setting the Loop ID and the AL_PA. The feature switches are located on the bottom of the drive.

To set the AL_PA:

__ 1. Determine an unused AL_PA for the drive and refer to Table 5 on page 21 for its corresponding LID.

__ 2. Locate the LID/status connector on the drive (see in Figure 6).

__ 3. Place jumpers on pins 1, 2, 3, 4, 7, and 8 as shown in Table 5 on page 21.

By using hard addressing, you can specify one of 62 valid AL_PAs for the drive. If you place jumpers on the four top and bottom pins on the right (a total of eight pins), the drive gets the AL_PA from a field in its vital product data (VPD). (A tape library can set the AL_PA in the VPD through the LDI interface.) If you do not place jumpers on any pins, the drive uses soft addressing to determine the AL_PA.

20IBM TotalStorage LTO Ultrium 2 Tape Drive