CN103743493A - MSP430-based low-power dissipation wireless temperature monitoring system and process - Google Patents

Abstract

The invention discloses an MSP430-based low-power wireless temperature monitoring system and a monitoring process, which includes a host system, the host system includes a central processing unit, a wireless module, a host computer, a power supply circuit and a keyboard circuit; a slave system, The slave system includes a central processing unit, a wireless module, a sensor, a power supply circuit and a keyboard circuit; wherein, the slave system transmits the collected data to the host system through the wireless module, and the host system central processor then The data is transferred to the host computer through the USB to serial port. The invention has a simpler structure and strong anti-interference ability, is suitable for on-site temperature measurement in harsh environments, and can be applied to the fields of warehouse temperature measurement, building air-conditioning control, production process monitoring and the like.

Description

A low-power wireless temperature monitoring system and process based on MSP430

technical field

The invention relates to a temperature monitoring system and a monitoring process, in particular to a temperature monitoring system and a monitoring method using a wireless transmission network.

the

Background technique

Temperature measurement and control are widely used in grain storage warehouses, intelligent building air conditioning control and other industrial and agricultural production and scientific research. The traditional method of temperature monitoring is to use analog sensors such as thermocouples, thermal resistors, and semiconductor PN junctions to obtain digital signals representing temperature values through signal sampling circuits, amplifying circuits, and AD conversion circuits, and then use microprocessors or DSPs to obtain digital signals that represent temperature values. deal with. The measured temperature signal starts from the non-electrical analog quantity received by the sensitive element and converts it into a digital signal that can be processed by the microprocessor. Designers have to consider many circuit links, and the number of components in the corresponding temperature measuring device is difficult to reduce. Consequently, the reliability and volume miniaturization of the product are affected. As a result, the entire detection system will have a large deviation, and the stability and anti-interference performance are poor. It is very meaningful to design a wireless temperature monitoring system with simple system structure, strong anti-interference ability, and suitable for on-site temperature measurement in harsh environments.

the

Contents of the invention

The purpose of the present invention is to provide a temperature monitoring system and monitoring method, which makes it simpler in structure and stronger in anti-interference ability than the existing temperature monitoring system, and is suitable for on-site temperature measurement in harsh environments, and can be applied to warehouse temperature measurement, Building air conditioning control and production process monitoring and other fields. The present invention can monitor 48 channels and display them friendly on the host computer. Practicality and ease of use have been considered in the design from the very beginning, which is of great practical significance.

In order to achieve the above object, the present invention provides a temperature monitoring system, which includes: a host system

system, the host system includes a central processing unit, a wireless module, an upper computer, a power supply circuit and a keyboard circuit; a slave system, and the slave system includes a central processing unit, a wireless module, a sensor, a power supply circuit and a keyboard circuit; wherein, The slave system transmits the collected data to the host system through the wireless module, and the central processor of the host system transmits the data to the host computer through the USB-to-serial port.

Further, in the above temperature monitoring system, the central processing unit is an MSP430 single-chip microcomputer, and the single-chip microcomputer is a 16-bit mixed-signal processor with ultra-low power consumption and a reduced instruction set.

Further, in the above temperature monitoring system, the sensor includes a digital temperature sensor DS18B20 and a photoresistor. Those skilled in the art can select appropriate sensors to read data and monitor according to actual needs.

Further, in the above temperature monitoring system, the wireless module includes an nRF24L01 single-chip radio frequency transceiver device, the nRF24L01 single-chip radio frequency transceiver device has a built-in frequency synthesizer, power amplifier, crystal oscillator, and modulator functional modules, and the nRF24L01 The single-chip RF transceiver device works in the 2.4 GHz to 2.5 GHz ISM frequency band, and incorporates enhanced ShockBurst technology, in which the output power and communication channel can be configured through the program.

Further, in the above temperature monitoring system, the USB-to-serial port circuit adopts TUSB3410, which is a bridge of USB-TO-UART port.

Further, in the above temperature monitoring system, the host system keyboard circuit includes an interrupt button.

Further, in the above temperature monitoring system, the slave system keyboard circuit includes four normal buttons and one reset button.

In addition, according to another aspect of the present invention, a temperature monitoring process of a temperature monitoring system is provided. The temperature monitoring system includes: a host system, the host system includes a central processing unit, a wireless module, a host computer, a power supply circuit and a keyboard circuit; a slave system, the slave system includes a central processing unit, a wireless module, sensor, power supply circuit and keyboard circuit; wherein, the slave system transmits the collected data to the host system through the wireless module, and the host system central processor transmits the data to the host through the USB to serial port machine. The temperature monitoring process includes a slave system program and a host system program; wherein, the slave system program includes initializing the host computer, initializing the central processing unit, and initializing the wireless module, the sensor reads data, and the sensor reads The data taken is sent to the wireless module for transmission, and the key value of the keyboard circuit is scanned; the host system program includes, initializing the USB to serial port, initializing the wireless module, and initializing the external interrupt, and the wireless module reads the data, Judge the legitimacy of the data, and send the data to the host computer through the USB-to-serial port. The host computer program completes the reading and writing of USB-to-serial port data, and the analysis and display of the data.

Further, in the above temperature monitoring process, the external interruption includes pressing a key to cause an interruption of the central processing unit, thereby interrupting the host system program.

The system of the invention is simple in design, stable and reliable, and convenient in operation, and can be applied in industrial production. Designed with an ultra-low-power single-chip microcomputer, it has lower power consumption. Compared with the traditional design, this design will be able to work for a longer time under the same battery power supply conditions. Data transmission is performed using wireless communication. The temperature monitoring system has the following advantages: 1. Low cost. 2. The construction period is short. 3. Good adaptability, almost not restricted by geographical environment, better and wider adaptability than wired communication. 4. Good scalability, if you need to expand, you only need to add nodes to achieve it.

the

Description of drawings

Figure 1 is a schematic diagram of the structure of the host system.

Figure 2 is a schematic diagram of the structure of the slave system.

Figure 3 is a schematic diagram of the host keyboard circuit.

Figure 4 is a schematic diagram of the slave keyboard circuit.

Figure 5 is a flow chart of the host system program.

Figure 6 is a flowchart of the external interrupt.

Figure 7 is a flow chart of the slave system program

Detailed ways

In the following, the present invention will be further explained and described in conjunction with the accompanying drawings and specific implementation methods, but the explanation and description do not constitute an improper limitation on the technical solution of the present invention.

Temperature Monitoring System

As shown in Fig. 1 and Fig. 2, the present invention provides a kind of temperature monitoring system, and it comprises: host system, and host system comprises CPU 1, wireless module 2, power supply circuit 3, host computer 4 and keyboard circuit 51; Machine system, the slave system includes a central processing unit 1, a wireless module 2, a power supply circuit 3, a sensor 4, and a keyboard circuit 52; wherein, the slave system transmits the collected data to the host system through the wireless module 2, and the host system central processor Then the data is transferred to the host computer 4 through the USB to serial port.

The central processor of the present invention selects a low-power consumption MSP430 single-chip microcomputer, which is a 16-bit single-chip microcomputer, adopts a reduced instruction set (RISC) structure, has 7 kinds of source operand addressing, 4 kinds of destination operand addressing, and concise 27 A large number of core instructions and a large number of simulation instructions; a large number of registers and on-chip data memory can participate in various operations; there are also efficient look-up table processing instructions, these characteristics ensure that high-efficiency source programs can be compiled. In addition, it also has the characteristics of fast computing speed, ultra-low power consumption, and rich on-chip resources. The temperature sensor 41 adopts a digital temperature sensor DS18B20, which has the characteristics of simple peripheral circuit, relatively fast response speed, high sensitivity, good stability, easy installation, and low cost. In addition, the temperature sensor 41 uses a single-bus protocol and only occupies one IO port of the MSP430 microcontroller 1 . The light intensity detection circuit is an extended function of this system. The light intensity detection circuit uses a photoresistor 42 as a sensor. The intensity of light will cause its resistance to change, thereby causing the voltage of the node to change. The node is connected to a converter to realize the detection of light intensity. The wireless module 2 transmits data, adopts a new single-chip radio frequency transceiver device, and works in the 2.4 GHz to 2.5 GHz ISM frequency band. Built-in frequency synthesizer, power amplifier, crystal oscillator, modulator and other functional modules, and incorporates enhanced ShockBurst technology, in which the output power and communication channel can be configured through the program. The USB-to-Serial bridge includes a USB-TO-UART port.

As shown in Fig. 3, the host system keyboard circuit 51 uses an interrupt mode, and each key uses an interruptible IO port of an MSP430 single-chip microcomputer, and a total of 4 keys 511, 512, 513, 514 are used. Due to the use of the interrupt button, the programming of the program is smoother, and the structure of the program is clearer.

As shown in FIG. 4 , the slave system keyboard circuit 52 is provided with 5 keys in total, including 4 conventional keys 522 , 523 , 524 , 525 and a reset key 521 . Programming is easy with a separate keypad.

The temperature monitoring system provided by the invention has the characteristics of simple peripheral circuit, relatively fast response speed, high sensitivity, good stability, easy installation and low cost.

Temperature Monitoring Process

The temperature monitoring process of the present invention will be discussed below with reference to FIG. 5 , FIG. 6 and FIG. 7 .

The invention provides a monitoring method for a temperature monitoring system, which includes: a host system, a host

The system includes a central processing unit 1, a wireless module 2, a power supply circuit 3, a host computer 4 and a keyboard circuit 51; a slave system, the slave system includes a central processing unit 1, a wireless module 2, a power supply circuit 3, a sensor 4, and a keyboard circuit 52 ; Wherein, the slave system transmits the collected data to the host system through the wireless module 2, and the central processor of the host system transmits the data to the host computer 4 through the USB to serial port.

The temperature monitoring process includes the slave system program and the host system program.

As shown in Figure 5, after the host system program starts S11, it first initializes S12, which is for the initialization of USB to serial port, wireless module, external interrupt, etc. Then enter the big loop and continuously execute the functions in the big loop. The main work to be done in the large loop is: first read the register microcontroller data S13, and then wait for the arrival of the data S14. Once the data is received, the program first judges the legality of the data S15, and if it is legal, sends the data to the host computer S16 through the USB to serial port. As shown in Figure 6, the key work of the host system program is set to interrupt mode. When someone presses a key, an external interrupt will generate S18, identify the key S19, and execute the key processing function S20, which will cause an interruption of the central processing unit, and then go to Execute interrupt service routine S21.

As shown in Figure 7, the slave system program includes temperature detection, light intensity detection, wireless data transmission, key scanning and so on. After the program starts S22, the slave machine first initializes S23, initializes the host computer, initializes the central processing unit and initializes the wireless module. Then enter the big loop and continuously execute the functions in the big loop. The main work done in the large cycle is: first read the temperature S25, read the light intensity S26, then send the temperature and light intensity data to the wireless module to emit S27, then scan the button S24 and execute the button processing function S28.

The system of the invention is simple in design, stable and reliable, and convenient in operation, and can be applied in industrial production. The ultra-low power consumption single-chip microcomputer has lower power consumption. Compared with the traditional monitoring technology, the invention can work for a longer time under the same power supply conditions. Using wireless communication for data transmission, the digital temperature sensor is connected to the microcontroller through a single bus. The system has a simple structure and strong anti-interference ability. It is suitable for on-site temperature measurement in harsh environments and can be applied to warehouse temperature measurement, building air conditioning control and production processes. monitoring and other fields. The present invention can monitor 48 paths.

It should be noted that the above description of the disclosed embodiment enables those skilled in the art to make various similar changes and modifications to the present embodiment. All deformations obtained or easily associative shall belong to the protection scope of the present invention. Therefore the present invention is not limited by this embodiment.

Claims (9)

1. A low-power consumption wireless temperature monitoring system based on MSP430, characterized in that, comprising: A host system, the host system includes a central processing unit, a wireless module, a host computer, a power supply circuit and a keyboard circuit; A slave system, which includes a central processing unit, a wireless module, a sensor, a power supply circuit and a keyboard circuit; Wherein, the slave system transmits the collected data to the host system through the wireless module, and the central processor of the host system transmits the data to the host computer through the USB-to-serial port. 2. The temperature monitoring system according to claim 1, wherein the central processing unit is an MSP430 single-chip microcomputer, and the single-chip microcomputer is a 16-bit mixed-signal processor with a reduced instruction set. 3. The temperature monitoring system according to claim 1, characterized in that: said sensor adopts DS18B20 digital temperature sensor and photoresistor. 4. temperature monitoring system as claimed in claim 1, is characterized in that: described wireless module comprises nRF24L01 single-chip radio frequency transceiver device, and described nRF24L01 single-chip radio frequency transceiver device built-in frequency synthesizer, power amplifier, crystal oscillator, modulation The nRF24L01 single-chip radio frequency transceiver device works in the 2.4 GHz to 2.5 GHz ISM frequency band, and incorporates the enhanced ShockBurst technology, in which the output power and communication channel can be configured through the program. 5. The temperature monitoring system according to claim 1, characterized in that: said USB-to-serial port circuit adopts TUSB3410, and the chip is a bridge of USB-TO-UART port, including a device for communicating with the host through the USB bus. All logic circuits necessary. 6. The temperature monitoring system according to claim 1, wherein the host system keyboard circuit includes an interrupt button. 7. The temperature monitoring system according to claim 1, wherein the slave system keyboard circuit includes four normal buttons and one reset button. 8. The temperature monitoring process of the temperature monitoring system according to claim 1, characterized in that: the temperature monitoring process includes a slave system program and a host system program; wherein, the slave system program includes, initializing the host computer, Initializing the central processing unit and initializing the wireless module, the sensor reads data, sends the data read by the sensor to the wireless module for emission, and scans the key value of the keyboard circuit; the host system program includes, initializing the USB The serial port is transferred, the wireless module is initialized, and the external interrupt is initialized. The wireless module reads the data, judges the legality of the data, and sends the data to the host computer through the USB to serial port. 9 . The temperature monitoring process according to claim 1 , wherein the external interruption includes pressing a key to cause an interruption of the central processing unit, thereby interrupting the host system program. 10 .

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