The Multi-ROB project will integrate up to 16 Read-Out Buffer (ROB) modules on one 9U VME card.
Why is this of interest ? 
  • with 1 ROB per card we would have 

  • ~ 2000 cards = ~ 100 crates = ~ 25 racks, 
    while with 16 ROBs per card this would be 
    ~ 120 cards = ~ 6 crates = 2 racks 
  • with > 1 ROB per card part of the multiplexing and switching required for LVL2 and Event Building hopefully can be done on the card and/or in the crate (feature extraction is also not excluded)
  • less cards may result in higher reliability
ATLAS DAQ system
Compact Robin Using the SHarc (CRUSH) 
(the white vertical connectors is for an S-LINK LDC,
the three black ones at the top are the SHARC links)

The first step to building a module having multiple ROBs, is the Compact Robin Using the SHarc (CRUSH).

In the CRUSH design study the aspects of compactness of design and low power dissipation are addressed, while at the same time it has been attempted to provide good programmability with respect to the required buffer management and also to provide a good testability of the design.
The CRUSH hardware consists of an S-LINK input, an ALTERA for buffer management and data checking, a 256K*32 memory and a SHARC processor from Analog Devices.


21 August 1997 Work is starting
9 September 1998 Design ready. PCB of the CRUSH is expected in two weeks time, simulations with actual SHARC processors have shown that the CRUSH can handle event rates up to 388 KHz.
4 November 1998 CRUSH is working. Power consumption is only 3 Watt.



CERN - High Speed Interconnect - S-LINK
Erik van der Bij - 4 November 1998