How to construct the map?
Updated on Mon, 2018-02-05 02:10. Originally created by lisa on 2018-02-05 01:33.
As of 4 Feb 2018, we do not know how to turn on an individual FEE channel. Tonko has hacked up a way for us to set Vbias and Vped for *all* FEEs.
Shining a bright light inside the FEE boxes or even at the FFCs or tiles produces a measurable response. In the photos below, we have turned off the P.S. to the FEEs in all but the SW box (PP07-12). If the mapping used by Wanbing's monitoring GUI were correct, we should see dark current above 0.01 uA in only the South half of the West wheel. Instead, we see it in 12 half-supersectors (the correct number) spread throughout the EPD representation. We observe the increased dark current appear in different tiles as we move the light around.
The scale was set such that the tile turns red when Idark exceeds 70 nA. The bias voltage here was 61 V. (Prior to the 2017 run, we hunted light leaks and were satisfied when Idark<100 nA at Vbias=61 V, under moderate light pressure. The result was good, so we plan to follow a similar tack this year. The "light pressure" applied above is more severe than what we applied last year.)
In 2017, we had 93 channels to deal with, so could manage with pen and laptop and patience. This year, with 744 channels, Wanbing's GUI will be crucial. But... it needs to have the correct map between (EastWestSide,PositionNumber,TileNumber) and (TUFFnumber,TuffBranchNumber,FEEnumber).
As a reminder, PositionNumber (a.k.a. PP) has range [1,12], and TileNumber (a.k.a. TT) [1,31].
There are two TUFF boxes, each with two branches in use. They connect to FEEs as listed below:
TUFF box 1 has nodename tuff03 and ip address 172.16.15.82
TUFF box 2 has nodename tuff06 and ip address 172.16.15.85
The "FEEnumber" has relevant range [0,11]. Each FEE in a FEE box has a small turn-screw set to a number in this range. In all of our FEE boxes, the left-most FEE in the cage has the turn-screw set to 0 and the right-most set to 11 ("B" in hex). Also, in all of our FEE boxes, the FEEs are connected lowest-PP-odd-tiles in left-most FEE, and highest-PP-even-tiles in right-most FEE.
Go here to see the map that results. Wanbing has to use this mapping.
Shining a bright light inside the FEE boxes or even at the FFCs or tiles produces a measurable response. In the photos below, we have turned off the P.S. to the FEEs in all but the SW box (PP07-12). If the mapping used by Wanbing's monitoring GUI were correct, we should see dark current above 0.01 uA in only the South half of the West wheel. Instead, we see it in 12 half-supersectors (the correct number) spread throughout the EPD representation. We observe the increased dark current appear in different tiles as we move the light around.
The scale was set such that the tile turns red when Idark exceeds 70 nA. The bias voltage here was 61 V. (Prior to the 2017 run, we hunted light leaks and were satisfied when Idark<100 nA at Vbias=61 V, under moderate light pressure. The result was good, so we plan to follow a similar tack this year. The "light pressure" applied above is more severe than what we applied last year.)
In 2017, we had 93 channels to deal with, so could manage with pen and laptop and patience. This year, with 744 channels, Wanbing's GUI will be crucial. But... it needs to have the correct map between (EastWestSide,PositionNumber,TileNumber) and (TUFFnumber,TuffBranchNumber,FEEnumber).
As a reminder, PositionNumber (a.k.a. PP) has range [1,12], and TileNumber (a.k.a. TT) [1,31].
There are two TUFF boxes, each with two branches in use. They connect to FEEs as listed below:
| TUFF | Branch | FEE box | positions served |
|---|---|---|---|
| 1 | 0 | NW | West PP01-06 |
| 1 | 1 | SW | West PP07-12 |
| 2 | 0 | NE | East PP07-12 |
| 2 | 1 | SE | East PP01-06 |
TUFF box 1 has nodename tuff03 and ip address 172.16.15.82
TUFF box 2 has nodename tuff06 and ip address 172.16.15.85
The "FEEnumber" has relevant range [0,11]. Each FEE in a FEE box has a small turn-screw set to a number in this range. In all of our FEE boxes, the left-most FEE in the cage has the turn-screw set to 0 and the right-most set to 11 ("B" in hex). Also, in all of our FEE boxes, the FEEs are connected lowest-PP-odd-tiles in left-most FEE, and highest-PP-even-tiles in right-most FEE.
Go here to see the map that results. Wanbing has to use this mapping.
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