Designates a bi-directional transfer of data for a single time slot of a T-1 or an E-1 digital frame between a T-1/E-1 device that connects to the digital service and the SCbus. Digitized information from the T-1/E-1 device is sent to the SCbus over the digital transmit channel. The response to this call is sent from the SCbus to the T-1/E-1 device over the digital receive (listen) channel.

A transmission channel that carries signals in digital form.

a logical grouping of digital bits