180 likes | 425 Vues
ZEBRA. Tom Cobb presented by Nick Rees. What is a zebra?. Zebras ( /ˈzɛbrə/ ZEB -rə or /ˈziːbrə/ ZEE -brə ) [1] are several species of African equids (horse family) united by their distinctive black and white stripes. What is ZEBRA?.
E N D
ZEBRA Tom Cobb presented by Nick Rees
What is a zebra? • Zebras (/ˈzɛbrə/ZEB-rə or /ˈziːbrə/ZEE-brə)[1] are several species of African equids (horse family) united by their distinctive black and white stripes.
What is ZEBRA? • A digital signal level converter and position compare box • 1U metal box with front panel BNCs and Lemos and rear panel encoder inputs
What does ZEBRA do? • Takes front panel single channel inputs • TTL, LVDS, PECL, NIM, Open Collector • And rear panel encoder signals • A+B RS422 Quadrature decoder, Z, connected • Pass the signals through some FPGA logic • Logic gates, position compare circuitry • Ouput front and rear panel signals • Same format as inputs, rewirable at run time
FPGA Design Spartan-6 FPGA 12 x LVTTL outputs 12 x LVTTL Inputs Logic Control 4 Ch x RS422 outputs 4 Ch x RS422 Inputs rs422 signals arm/gate/ pulse Position Compare SRAM Ctrl 2MBx8SRAM ctrl ctrl 16 Mbit SPI Flash UART Ctrl Communications (8-bit soft Micro Controller) RS232 256x16 Config BRAM
How do you configure ZEBRA? • 115200 baud RS232 link to EPICS • Parameters set/get via EPICS • Logic blocks rewired via the system bus • Data download of position/time information • Save to internal flash
What doesn’t ZEBRA do? • Analogue • Signals < 20ns • Low latency data transfer • High bandwidth data transfer • Sequencing
When can I have one? • Available from Quantum Detectors • http://www.quantumdetectors.com/products/zebra • Should be in stock by Christmas
Ideas for Zebra2 • Ethernet interface • TCP not UDP, so... • Zinq, rather than Spartan6 • IOC on board(?) • Additional encoder capture/trigger signals: • Analogue input • Serial encoder input • Event reciever (?) • Better support for counters • Differences? • More gates