National Semiconductor Corp’s Datachecker Systems Inc, based in Santa Clara, California, has signed a marketing and service agreement with Telepanel Inc, producer of point of purchase price and information display systems for the retail industry; the agreement gives Datachecker exclusive North American distribution and service rights for Telepanel’s computer-controlled, electronic shelf-based Price and Information Network over the next five years, and distribution rights on a non-exclusive basis in Europe and the Pacific Basin.