Remreed Switching Networks for No. 1 and No. 1A ESS: Remreed Line Scanner

The No. 1 ESS line scanner is used to detect originations on subscriber lines. The original design, used in ferreed line link networks, is described in Ref. 1. The new scanner design takes advantage of the remreed network packaging and interconnection technologies to achieve a significant reduction in frame and unit wiring, manufacturing costs, and floor space by integrating the line supervisory element with the connectorized network fabric. Additional cost and space savings, reduced wiring, and improved reliability are achieved through the use of an integrated-circuit controller. The new scanner is referred to as the remreed line scanner because of its physical packaging with the remreed network fabric. 1.1 Scanner function Most of the No. 1 ESS scanning logic is built into the scan programs. A scan request is generated in the central control in small offices or in the signal processor in large offices and transmitted to the scanner control over the peripheral unit-address bus. Each scanner in an office monitors the state of 1024 scan points, organized in 64 rows of 16 scan points in a particular row specified by the order. The scanner interrogates the 16 points specified by the order received over the peripheral unit-address bus and responds with a 17-bit message on the scanner597