A Multi-protocol Bus Applied To PHOS

PHOS(Photon Spectrometer) mentioned in this thesis is used for photon detecting, which is one of the detecting systems in ALICE(A Large Ion Collider Experiment) arranged by CERN(European Organization for Nuclear Research). Its function modules consist of data, configuration, monitoring and trigger. To implement the function of monitoring, a controller based on FPGA is set on the FEE(Front End Electronics) card of PHOS. In order to monitor and set the work situation, this module needs to communicate with numbers of peripheral equipments including RCU(Readout Control Unit), ADCs used for monitoring environment and work situation, MCU(Micro Control Unit) and DACs used for high voltage bias. Thus a multi-protocol bus is formed. And bus arbitration is necessary when two or more equipments access the bus.For the requirement, a design of the multi-protocol bus applied to PHOS is proposed. In the multi-protocol bus, there are numbers of bus, including I2C bus, SPI bus, Altro bus and RCUI2C bus. Altro bus, a kind of parallel bus for high-rate data transmission, communicates with RCU; I2C bus, SPI bus and RCUI2C bus are all serial bus for low-rate data transmission. I2C bus is used to communicate with MCU while SPI bus is for DACs, RCUI2C bus for slow control by RCU.The work consists of design and realization. First, code the project of the multi-protocol bus in Verilog HDL. Then, simulate the project with the EDA tools of ModelSim and Quartus II. The simulation results indicate that the design meets the requirement. After that, synthesize the project, plat and fit, generate the bit or prom file, finally download it into the FPGA chip, debug and test. The test results indicate the code of the project implements the design of the multi-protocol bus and meets the requirement of control module on FEE.The design and realization of the multi-protocol bus in this thesis can provide some reference to other design with the similar requirements because of its certain universal.