Abstract: Real time measurement and dynamic display of body surface potential maps play a important role in solving the inverse problem of electrocardiograph.In this paper a Z-80 microcomputer based system is presented,it enables simultaneous observation of ECG data of 60 lead points in a potential pattern.The instrument is composed of 4 components:a lead electrode system contained 64 electrodes;a analogue signal processing system;a data processing system;a data output,display system.By means of instruction of Z-80 the instrument can store sample data in RAM with out DMA methodand data processing system bas own complete function.