Uli shows an updated block diagram of JEM1. He explains the main building blocks and points out the modifications wrt the diagram shown last November: G-links and optical transmitters reside on a separate daughter module now, and the CAN controller is attached to the jet processor rather than the sum processor, due to pin count limitations. Uli shows a list of the few components mounted on the main board itself.

JEM1 is currently being manufactured by Rohde & Schwarz. They are managing the comlete project from component procurement to assembly. 

Uli reports the current hardware status (main boards, input modules and G-link modules).

Uli reminds us of the JEM algorithms and points out some modifications on the implementation required to allow for transition to the production modules. The energy sum algorithm is partitioned into FPGAs differently and the Ex/Ey calculation is now performed on jet elements rather than energy sums. The resolution on the energy sum data path has been increased by two bits after the previous joint meeting. Uli explains firmware modifications required to make the code suitable for the Virtex-2 FPGAS and the slightly changed JEM1 architecture. Uli reports the current firmware status.


JEM1 is expected to arrive in Mainz in a weeks time. Further input module and G-link modules are should be available in April. 3 more main boards will be assembled in May with the actual assembly taking approximately one week. Components are available. Firmware should be fairly stable in a months time. It is envisaged to keep JEM0s up and running until a minimum of two JEM1s are commissioned.