I/o module for a serial multiple data system with a data bus integrity

Abstract

A programmable data link module is used on a time division multiplex data bus. The module receives data from the data bus during a selected time slot for a selected number of frames. The data link module includes an input circuit for generating a data output signal data to the data bus in response to input signals from an input device coupled to the module. The input circuit includes a data bus integrity checker for determining whether the data bus is intact. A test signal is sent by a master clock source to the data link module and if it is properly received, the integrity checker will permit the data link module to received data signals from the data bus.