Design of intelligent blood parameter analysis system based on SPCE061A

With the development of intelligent control, the analysis of blood cell status and parameters has also been continuously using the latest electronic, optical, chemical and computer technologies to meet the requirements of clinical work for blood cell analysis. Intelligent instruments can reduce the intensity of manual labor, speed up the processing of specimens, and make many operations more standardized and reduce individual differences between operators.

1 Overall system design

The blood parameter analysis system was designed using the SPCE061A single-chip microcomputer of Lingyang Company. The liquid circuit is controlled by electromagnetic valves. The timing circuit is designed according to the actual requirements of the blood analyzer, which can realize intelligent voice prompts of the detection parameters. The overall structure of the system is shown in Figure 1.

The system controls the flow path of the entire instrument through 13 solenoid valves and 1 pressure pump. When the control system receives the command, it opens the corresponding blood sample path, and the various liquid paths are isolated and connected through solenoid valves. The control is implemented in the Lingyang SPCE061A microcontroller. The I/O port of the SPCE061A microcontroller is only 32 bits, and the I/O port of the system will not be enough, so EPM 7128 is used as the logic control unit. Communicate with SPCE061A through the universal asynchronous serial port UART to realize the processing and alarm of the detection results of the working status of each loop. The feedback comparison chip uses 339, and the output is transmitted to EPM7128 for processing, and finally fed back to the microcontroller. The audio amplifier circuit uses the SPY0030 integrated chip, which can achieve a good amplification effect.

2 System Hardware Design

The hardware circuit is mainly divided into SPCE061A minimum system, solenoid valve drive circuit and CPLD peripheral circuit.

2.1 Minimum System

Connect the crystal oscillator and the resonant capacitor, and connect the corresponding capacitor and resistor to the RC input VCP terminal of the phase-locked loop voltage-controlled oscillator to achieve the minimum system. Connect 0.1μF decoupling capacitors to the other unused power supply terminals and ground terminals to improve anti-interference ability.

2.2 Power supply

The core voltage of SPCE061A is required to be 3.3 V, while the voltage of I/O port can be 3.3 V or 5 V. Therefore, two power supply interfaces are designed: 5 V and 3.3 V. For I/O port, these two voltage levels are selected by jumper.

2.3 Audio Output

The MCU audio output signal is a current signal output by the internal D/A converter. It is first split externally, then converted from current to voltage signal, and finally passes through the SPY0030 audio amplifier and output to drive the speaker.

2.4 Solenoid valve drive

The output voltage of the I/O port of the Sunplus microcontroller is +5 V, and the maximum output current is about 10 mA. The system uses a two-stage amplifier drive. The first stage is a PNP type 9012 SMD transistor, and the second stage is an NPN type 8050 SMD transistor.

For the convenience of system debugging, RS 232 chip is used to realize the communication between SPCE061A and PC.

3 System Software Design

3.1 Delay module

In order to achieve accurate delay, the delay program uses timer interrupts to achieve a certain delay. Multiple interrupts are used to generate a certain delay. The flow of the interrupt subroutine is shown in Figure 2.

3.2 Serial port module

The communication between SPCE061A and LPC2210 is realized through the universal asynchronous serial port UART. The serial port receives and sends by multiplexing the IOB port. IOB10 is the data transmission pin Tx, and IOB7 is the data reception pin Rx. UART can receive data in a buffered manner, that is, it can read the data before the current data in the buffer. The serial port sending subroutine flow is shown in Figure 3.

4 Conclusion

An intelligently controlled blood parameter analysis system was designed, which can analyze various parameters of blood cells, realize intelligent operation, reduce manual operation errors and data errors, and achieve high-precision blood parameter measurement. The control principle of this system can also be applied to all related fields, such as power systems with solenoid valve control, industrial control systems, dam control systems, and traffic light control systems, etc., and has certain use value.