PULSE TO DIGITAL CONVERSION SYSTEM

THE COMPLETE DESIGN IS PRESENTED WITHIN THIS PROPOSAL FOR A SYSTEM WHICH WILL PROVIDE A PRECISE, ONE-STEP CONVERSION DIRECTLY FROM A PULSE TRAIN INPUT TO A DIGITIZED PULSE RATE OUTPUT. IT IS A DISTRIBUTED PROCESSOR SYSTEM EMPLOYING A MASTER CONTROL PROCESSOR AND FROM 2 TO 30 IDENTICAL PULSE MODULES. THE PULSE MODULE IS A STANDALONE UNIT WHICH PERFORMS THE PULSE PERIOD MEASUREMENT. THE MICROPROCESSOR WITHIN EACH PULSE MODULE PERFORMS THE PULSE PERIOD TO PULSE RATE CONVERSION. THE RESULTANT PULSE RATE IS FORMATTED AND LOADED INTO THE MODULES 16-BIT OUTPUT BUFFER. THIS BUFFER IS ACTIVATED BY COMMAND FROM THE MASTER CONTROL PROCESSOR. THE MASTER CONTROL PROCESSOR PROVIDES FOR INTERNAL/EXTERNAL SYNCHRONIZATION AND AUTOCALIBRATION. THE INTERNAL SYNCHRONIZATION PERMITS THE MASTER CONTROL PROCESSORS TO DESIGNATE WHICH OF ITS 30 PULSE MODULES WILL PLACE ITS DATA ON THE COMMON 16-BIT EXTERNAL DATA BUS. EXTERNAL SYNCHRONIZATION SERVES AS THE TIMING INTERFACE BETWEEN THE MASTER CONTROL PROCESSOR AND THE EXTERNAL DATA RECORDER. AN INTERNAL REFERENCE FREQUENCY SOURCE IS USED TO PROVIDE A PRECISE TIME BASE FOR USE BY THE PULSE MODULE IN AN AUTOCALIBRATION MODE.