We present a transmitter for a scalable multiple-access inter-chip link that communicates binary activity between two-dimensional arrays fabricated in deep submicrometer CMOS. Transmission is initiated by active cells but cells are not read individually. An entire row is read in parallel; this increases communication capacity with integration density. Access is random but not inequitable. A row is not reread until all those waiting are serviced; this increases parallelism as more of its cells become active in the mean time. Row and column addresses identify active cells but they are not transmitted simultaneously. The row address is followed sequentially by a column address for each active cell; this cuts pad count in half without sacrificing capacity. We synthesized an asynchronous implementation by performing a series of program decompositions, starting from a high-level description. Links using this design have been implemented successfully in three generations of submicrometer CMOS technology.