The Simulation-test Of Low Energy X-ray Detector And Development Of The Data Transmission System

The Hard X-ray Modulation Telescope (HXMT) is independently researched by China for the exploration of extragalactic X-ray band information. It is directly modulation-imaging by the X-ray in low energy, medium energy and high energy. In this thesis, the module software of the low energy detector box and electronic-control box has been simulation-tested. At the same time, the special data Transmission system has been developed for the data transmission at the experiment stage of the detector box.The studies and the results are as follows:1. The software of the FPGA in the low energy detector box and electronic control box has been comprehensively simulation-tested. The test platform is Libero IDE9.1and Modelsim. The test results show that the requirement of software has been met basically. The functions of the detector box are mainly consisted of collecting the CCD data, configuring the digital to analog converter (DAC), the drive of the detector and the working parameters. The functions of the electronic control box are mainly consisted of receiving and uploading the data of detector box; receiving the instruction and injecting instruction to the detector box. In the test, the inconsequence has been found is that the requirements of configuration of the drive in the detector box are not met. The suggestion has been provided after analyzation, and the requirements have been met by the program after the modification.2. The circuit board and programs of the Data Transmission System have been designed. For the hardware, the high speed processing ability has been achieved by the master control chip of the circuit boards (FPGA) which has the parallel processing ability. In order to ensure high reliability of signal transmission, the technique of Low-Voltage Differential Signaling (LVDS) which has high noise suppression has been adopted by the system. For the software, the program has been written with hardware description language (VHDL), there are the functions that receive and pack the data and upload it, receive and inject the instruction, clock output. At the end of the part, the results of the simulation-testing show that the requirements have been met by the program.3. The functions of the Data Transmission System have been tested. The result of the FPGA test shows that the task of data transmission has been completed by the system. The voltage of the power-supply module is stable when the system is powered on, the FPGA and LVDS modules have been working normally. The data has been gathered by the system for a long time; the instructions have been received from PC and transmitted by the LVDS.