ATLAS Level-1 Calorimeter Trigger
Hardware Progress Meeting - 13 April 1999

Minutes

Present: Eric Eisenhandler, Norman Gee, Tony Gillman, Bob Hatley, Viraj
Perera, Richard Staley

1. ACTION list from previous meeting (31-3-1999):
a) Richard has almost completed writing up the results of the backplane
transmission tests but  wants to do some further measurements with the CMOS
system at reduced supply voltages.
b) Tony has had a positive reply from Werner Witzeling regarding the loan of
some ATLAS racks to RAL, which will be followed up.

2. CMM architecture update
Norman (in collaboration with Kithsiri, Sam and Uli) has produced a document
discussing the issues relating to the design of a common Merger module. It
seems likely that the Sum Merger module would remain as a separate design.
Kithsiri is starting to look at the tools (Cadence) needed to set up a model
to simulate the backplane design, looking for effects such as crosstalk,
etc. A hardware demonstration may subsequently be needed if the simulation
results are encouraging (necessary but not sufficient).

3. DSS system:
a) Serial data connectors
Bob reported that the Robinson Nugent connectors were unsuitable as they did
not produce cable-mounting parts. A long discussion yielded no real
conclusions - suitable connectors were either on long delivery or only
available in very large minimum order quantities, or both! However, after
the meeting a decision was reached to accept the long lead-time on ordering
the Berg parts, as it is now probable that the DSS mother-board will be
delayed. Alternative (readily-available) coaxial connectors - SMR - will be
used for the G-link boards.
b) DSS motherboard design status
Viraj reported that Kevin has now almost completed the schematics, and he
now confidently expects that they will go to the Drawing Office for layout
during the week beginning 19th April.
c) LVDS daughter-cards layout status
Richard reported that the Receiver card layout is complete, assuming use of
the Berg connectors is confirmed, and that the Transmitter card will also be
similarly complete by the week beginning 19th April.
d) G-link daughter-cards layout status
Bob reported that the Drawing Office has almost completed component
placement for both the Receiver and Transmitter cards, but again it is
crucial to confirm the connector types. Tony said that he had received a
request from our Heidelberg colleagues for a completion date for the
Receiver card. Assuming layout completion by the week beginning 19th April,
assembled Receiver cards should be available by mid-May.

4. Conference submissions
Eric had circulated a request among the collaboration to ask who was
intending submitting papers to the IEEE Nuclear Science Symposium or to LEB
(both taking place this year in the USA). From Heidelberg there may be
papers on the PreProcessor Readout Bus architecture and the MCM, and from
the UK groups papers on the DSS system and ROD prototype design. Eric warned
that submission deadlines for Abstracts were fast approaching!
ACTION: Collate list of proposed papers - Eric.

5. ROD prototype:
Norman reported that the modifications and questions thrown up by the Review
were gradually getting resolved. Two current issues are the requirement from
CERN that RODs are designed to the VME64 specification, and the recent
realisation that the trigger-type information arrives from the TTC system
very late, implying the need for buffering and queuing of many
part-assembled events in the ROD, each awaiting the addition of the
trigger-type.

6. CCM prototype
There was some discussion about adding functionality in the CCM to provide
an input for prompt trigger-type information direct from the CTP, if it were
desired to read out extra time slices from the CPM serialising ASICs for
calibration triggers, but it was decided to achieve this by always reading
out long time frames and suppress when unwanted by post-processing in the
RODs.
Following discussions with several people Viraj has re-structured and
simplified the specifications document, and with a few further changes it
should be possible to release it on to the Web for review. Tony will
circulate a note to the appropriate people when this happens.

7. Planning for system tests:
a) Exploitation plan
Norman has produced a draft plan describing the various stages needed to
test the links using the DSS module(s), which he will put up on the Web.
b) Tony noted that the timescales had unfortunately extended much further
than originally anticipated, but we could now foresee the system tests
taking place in June.

8. Current Review status
Tony said that he will write a short summary of the outcome of each PDR, to
be put up on the Web. In some cases this is not yet possible, as the
specification documents have not been finalised.
ACTION: Summarise outcomes of completed Reviews - Tony.

9. Any other business
Norman said that ATLAS (UK) has requested that we provide by 20th April an
estimate of the projected UK spend in FY1999/2000. Tony agreed to do this.

* Next meeting - Tuesday 20th April at 13.30 in CR02, R1 at RAL.

Tony Gillman