For intercom exchange, it has following facilities: direct call--when two extensions are calling each other, the system will connect them directly.

• 在内线功 能上，实现了如下功能：主叫等待：主叫拨号后，如果未叫通被叫或 被叫忙，不需重新拨号，只要等待，系统自动完成接续。