摘要:
At least one connection for the communication exchange and one connection for the communication of frame clock signals is provided between centralized equipment, for example a switching matrix network, and decentralized equipment, for example line trunk groups. The frame clock signals indicate the beginning of a transmission frame utilized for the channel-oriented communication exchange. The operating condition information, for example equipment is "active" or "inactive" are communicated by pulse-duration or pulse-pause modulated or by n-coded pulse duration or pulse-pause-modulated frame clock signals.