Design of digital telephone system oriented for training

In the enterprise training, a digital telephone system with special functions is needed and there are no such products on the market. In this paper, a digital telephone system for training is designed based on CAN (Controller Area Network) bus and Ethernet. The SPC (Stored Program Controlled) telephone exchange is designed with distributed multi processors which communicate by CAN. In the system, the SPC telephone exchange sends call information to the upper computer for voice broadcast through the Ethernet and the upper computer sends control information to the SPC telephone exchange through the same line. The structure and working principle of the digital telephone system for training are elaborated and the design idea of the system hardware circuit is introduced briefly. The design idea of the system software is introduced in detail and the flow charts of some programs are showed. Practice shows that the digital telephone system oriented to training can work reliably.