Study On Opto-electronic Digital Intelligent Detection System Of Blood Coagulation Time

Detecting technique of blood coagulation time is mainly used in diagnosing the cruor disease and testing the medicine effect for preventing concreting and so on. The research on intelligent blood coagulation instrument which can reliably detect blood coagulation time in real-time has the widespread application and the vital scientific significance. Combined with the domestic and international status quo of blood coagulation instrument, a dual-CPU system structure is put forward, taking MCS-51 MCU as the core, dual-port RAM as the deliver hinge and opto-electronic conversion circuit as the sensor. At the same time, an optic-electronic digital intelligent detection system of blood coagulation time is set up and designed.In the paper, the former single CPU system structure is replaced with dual-CPU system structure for raising the credibility and the speed of the whole detection system; in order to reduce the cost, the low-cost MCU is used as core for setting up the detection system of blood coagulation time. At the same time, the serial communication is replaced with dual-port RAM communication to make it possible that the dual-CPU system achieves high-speed and reliable detection.The main work completed is summarized as follows:1. The structure of the detection system of blood coagulation time is designed based on detailed analyzing and discussing the characteristics of blood coagulating process.2. AT89C51, low-cost MCU, is used for main and subordinate CPU of the system. The main CPU divides the work with subordinate CPU and then cooperates with it. The subordinate CPU mainly completes the high-speed data sampling with the help of AD574A, and the main CPU mainly completes data processing of the detecting system.3. A dual-port RAM interface circuit is designed to realize the fast communications between main CPU and subordinate CPU, at the same time ,the RS-232 interface circuit is designed so that the system can communicate with PC.4. A LCD interface circuit is designed to display the blood coagulation time and describe the blood coagulation curve.5. An opto-electronic conversion circuit with good capability is designed to catch the scatter light. 6. All programs of the detecting system are programmed with assembly language.7. A test device for detection system of blood coagulation time is set up, and an experiment of PT detection on alive chicken's blood is conducted with the detecting system whose hardware and software are debugged.