RESUMO
Objective: To design an ambulatory blood pressure measuring system based on control of single chip microcomputer AT89C51 so as to accurately measure the blood pressure of human body. Methods: In the design, single chip computer AT89C51 was used as main controller, and pressure transducer MPX5050GP was used to collect signal of blood pressure of human body, and then through calculated and processed of single chip microcomputer to measure the blood pressure value. The peripheral design adopted on-off circuit and liquid crystal display (LCD) to monitor the start control and blood pressure value of system. Results: This system could convert the blood pressure signal of human body into electrical signal through pressure transducer. And after these weak electrical signals were amplified and filtrated, they were further convert into digital signal so as to be inputed in single chip microcomputer. And then, these measurement value were finally displayed on LCD through calculating and processing of main program for these signals. The results of this system has well stability, and its largest indication error was 3 mmHg, which was in the permissible error range, and the detection was qualified. Conclusion: The system can accurately measure the blood pressure of human body, and it has the advantages of small size, convenient using, clear display and so on.