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Binary Search of Cable Segment

Taking apart the cable segment to diagnose it is a tedious procedure fraught with the danger of making things even worse than they were when you started. Be very careful. I no longer power down the whole cable segment, but I am very careful not to put things in upside down or backwards, and I make very certain that the cables are strain relieved and pushed firmly, but not violently, in.

Connectors and cables can be moved around, but the rule is that you need terminators at both ends of the cable segment. One one end, they are in the Cable Segment Ancillary Logic module in the master crate, and the other end is the card hanging by two cables from the ADC1 crate.

At the time of writing, the cable segment emerges from the back of the Ancillary Logic, and goes to the trigger SSP, then back to the master rack to pick up the FERA SSP and the two master SSP's. Of course, the Master SSP crate must be on the cable segment, because it also contains the BBFC FASTBUS interface, which is the window from the online computer into FASTBUS> Thus, the minimal cable segment configuration consists of the Master SSP's, the FERA SSP, and the trigger SSP. This configuration would like this to sspar:

Command:scan   
 Scan from route: 000008h - From the CFI's crate segment
 on through the SSP at geographic address:  8 (  8h)  to its cable segment
 At:  1 (  1h) is: SSP  (SLAC Scanner Processor)................... ID: 0106
 At:  2 (  2h) is: SSP  (SLAC Scanner Processor)................... ID: 0106
 At: 31 ( 1Fh) is: Kinetics F290 display........................... ID: 1007
 At:255 ( FFh) is: GAC card, cable seg............................. ID: 1002

From here, you will need to follow the path of the cable segment, adding SSP's until you find the problem.



John Haggerty
Thu May 4 15:36:13 EDT 1995