NIRSPEC black boxes

The NIRSPEC host computer waimea communicates with NIRSPEC's on-board transputers over a SCSI-protocol connection, but the medium between them is an optical fiber. At each end, there is a small SCSI/Fiber extender box, sometimes called the "black box." This is actually the name of the manufacturer and not a description of its appearance!

There is one box in the Keck II computer room near waimea, and there is another box on board the instrument, in the small center racks near the Lakeshore temperature controller.

In normal operation, both black boxes should have their "Link Active" lights illuminated. If the light is not lit then you know something is wrong. Unfortunately, if the light is lit this is no guarantee things are fine.

If the stop_nirspec or kill_all commands leave 1 or 2 relic server processes hanging around, the most likely cause is a stuck communications link with the transputers requiring a power cycle by someone on the summit.

Power Cycling the Black Boxes

The power switchs are small rocker switches on the back of the boxes. You should be careful not to move the box around too much. Inadequate strain relief of cabling into and out of the boxes as been a problem in the past.

The more likely of the two black boxes to have trouble seems to be the one in the computer room. To power cycle this one ask the swing tech or OA to go into the K2 computer room and cycle power on the SCSI/Fiber extender box near waimea. There are a few of these boxes in the computer room so tell them it is labelled "NIRSPEC TRANSPUTER" in white label tape on its side. Have them check the label and look at the picture if they are in any doubt about whether they've got the right one.

To get to the on-instrument black box requires removal of the right side small center cover. Here is wide view picture with all three covers removed. Here is a closer in picture with just the small center cover removed. The correct black box is labelled "transputers".