This paper introduced the principle of calling party number identifier (CID) and its design in the multi_functional telephone.

分析了主叫号码显示原理及其在多功能电话机中的设计。

youdao

This paper introduced the principle of calling party number identifier (CID) and its design in the multi_functional telephone.

分析了主叫号码显示原理及其在多功能电话机中的设计。

youdao