| 摘要 |
<p>An emulator according to the invention essentially comprises a central-processing unit (1050), frame multiplexing and demultiplexing circuits (1054 and 1055), line transmission and reception circuits (1056 and 1057), means of interfacing with an external system (1051, 1052 and 1053), and a time base (1059). The emulator transmits downward test frames (TD) and analyses upward test frames (TM) transmitted in response by terminal devices. The information contained in the frames is processed by the central-processing unit so as in particular to determine the condition and quality of various links established with the terminal devices. The emulator is more particularly designed to be integrated in a bus testing and measuring system according to the invention. The system comprises a main piece of equipment connected to a bus and which includes the emulator and terminal-simulation devices. Circuits for measuring resistance, electrical isolation, and crosstalk, as well as a circuit for detecting a perturbing potential are also included in the system and permit very full testing and measurement of the characteristics of the bus. <IMAGE></p> |
