1. TTP Related SW December 4th 2007 Juha Petäjäjärvi December 4th 2007 Juha Petäjäjärvi Totem Test Platform

2. TTP in Numbers Simple I 2 C loop with one CCU and FEC 2 I 2 C channels, data from one at the time 4 (GEM) + 1 (RP) sockets for hybrids 4 VFATs used effectively Programmable I 2 C address for one GEM 4 fifos for data 1024 x 32 bits each (85 VFAT frames) Programmable trigger pattern up to 1024 triggers, multiple trigger modes Fifo for S-bit information (256 entries)

3. Related Software Compatible with FecSoftware without any modifications I 2 C functionality Inherited lots of software from Preshower Crepe functions (trigger & data readout etc.) Use together with vfat_controller Slink readout + TBB triggering -> Crepe trigger & data readout Code optimization (I 2 C access slow via USB)

4. I 2 C Performance via USB One USB transaction, 4 ms Changing one value on VFAT requires 10-20 transactions Write & read all registers on one VFAT, 40 sec Example: Pulse scan using VCal range of 10 for 4 VFATs 150 000 transactions Theoretical minimum 10 minutes

5. Possible Performance Improvements User level USB driver -> kernel level Implemented, being tested by Wojciech (Preshower) USB 1.0 (12 Mbps) -> USB 2.0 (480 Mbps) Needs firmware modifications I 2 C bit rate 100 kbps - 1Mbps only And/or simply reduce the number of USB transactions...