Test access system for a digital loop carrier system

A test access system in a digital loop carrier communication system having at least first and second terminals connected by a digital transmission line, each of said first and second terminals having a plurality of analog ports for analog signals and each of said first and second terminals having at least one digital port connected to said digital transmission line for digital signals, each of said first and second terminals having a plurality of channel units having first ports and a second port, said first ports connected to said analog ports, respectively, and at least one digital interface unit having a first port connected to said second port of said channel units and a second port connected to said digital port, comprising:

• a channel diagnostic unit connected via a first bus to each of said analog ports and said first ports of said channel units and connected via a second bus to said first port of said digital interface unit;
• a system access unit connected via said first bus to each of said analog ports and said first ports of said channel units and connected via said second bus to said first port of said digital interface unit;
• said channel diagnostic unit at least selecting a signal test path and said system access unit at least provides for monitoring and/or insertion of test signals on said signal test path;
• and
• said channel diagnostic unit and said system access unit having means for switching signal lines in said first and second buses to establish said signal test path.

A test access system in a digital loop carrier communication system having at least first and second terminals connected by a digital transmission line, each of said first and second terminals having a plurality of analog ports for analog signals each of said first and second terminals having and at least one digital port connected to said digital transmission line for digital signals, each of said first and second terminals having a plurality of channel units having first ports and a second port, said first ports connected to said analog ports, respectively, and at least one digital interface unit having a first port connected to said second port of said channel units and a second port connected to said digital port, comprising:

• means for establishing at least a signal test path connected via a first bus to each of said analog ports and said first ports of said channel units and connected via a second bus to said first port of said digital interface unit;
• means for monitoring connected via said first bus to each of said analog ports and said first ports of said channel units and connected via said second bus to said first port of said digital interface unit;
• and
• said means for monitoring also having means for insertion of test signals on said signal test path.