Design of a NIM-based DAQ system

In order to satisfy the requirements of beam measurement in the heavy ion medical machine and other small nuclear physics experiments, we designed and built a nuclear instrumentation module-based data acquisition system. This is composed of a set of functional modules and a purpose-built bus. One of the modules operates as a master, collecting data from the other slave modules. It then sends the data to the back-end computer via Ethernet. In addition to the hardware, dedicated software has been designed and implemented. In this paper, we provide a detailed description of the architecture of the system, the data frame, and the software. The bus is the central part of the system. It can transmit data from the slave modules to the master at 33 MB/s. The frame used to transmit the data also ensures its integrity and monitors the hardware architecture. The client software is designed to process data in real time and store data on a hard disk for later analysis.