Method for realizing grouped dormancy and awakening of hydrostatic level gauge in time slice polling mode

Abstract

The invention relates to a method for realizing grouped dormancy and awakening of static force level gauges in a time slice polling mode, which comprises the following steps of: grouping all static force level gauges mounted on an RS485 bus, and assuming that the static force level gauges are divided into N groups; the system divides an acquisition period into N time slices according to a sequence, each time slice only activates the static force level gauges of one group, so that the static force level gauges of other groups are in a sleep standby mode, and after measurement data acquisition of all the static force level gauges in the group is completed in the time slice, the static force level gauges in the group are stored in the sleep standby mode. And the system automatically sets all static levels in the group to enter a sleep standby mode. And integrally activating the static force level gauges of the next group in the next time slice to complete data acquisition of the next group. And repeating the steps, and completing data acquisition of all the static force level gauges in the N groups in sequence according to the time slices in the whole acquisition period. And the total peak power consumption of the system is reduced to 1 / N of the original power consumption, so that the purposes of greatly increasing the number of connectable static level gauges and expanding the communication distance are achieved.

Description

Technical Field

[0001] The invention belongs to the field of communication technology, and in particular relates to a method for realizing group dormancy and awakening of a static level instrument in a time slice polling manner. Background Art

[0002] The automated static leveling system, which has been developed since the 1990s, is a high-precision measurement system used to measure relative elevation changes. The static level uses the principle of connecting liquid. The liquid levels of the liquid storage tanks connected by multiple universal connecting pipes are always at the same level. By measuring the liquid level heights of different liquid storage tanks, the relative differential settlement of each static level can be calculated. The entire system consists of multiple static levels and mounting brackets, liquid pipes, gas pipes, and collectors. It is mainly suitable for vertical displacement monitoring between multiple points for long-term and high-frequency monitoring of geotechnical and structural safety engineering.

[0003] The topology of the system transmission is one master with multiple slaves. The data collector is connected to the static level of all measuring points through the RS485 bus. That is, one data collector is connected to multiple static levels. The system topology is shown in Figure 1 .

[0004] Taking the tunnel, a typical installation application scenario of the static level measurement system, as an example, the characteristics of the target engineering environment, which has a narrow and long physical space and a large number of measuring points, make the number of static level measurement points that the measurement system can connect and the length of the communication distance become important technical competitive advantages.

[0005] Normally, in order to reduce the complexity of system networking and reduce costs, the power supply of the hydrostatic level and the RS485 differential data signal line are integrated into a four-core cable. The four cores are DC power supply VIN, ground GND, and RS485A, B differential signal lines. The power supply VIN of the hydrostatic level at each measuring point is output from the data collector, and the hydrostatic level at all measuring points is supplied through the entire cable. The data collector acts as a communication host and communicates with all the hydrostatic level slaves through the RS485 A, B differential signal lines in the cable to obtain measurement data. See Figure 2 .

[0006] Theoretically, the maximum number of devices that can be mounted on the RS485 bus is 256, and the longest transmission distance can reach 1200 meters. In actual applications, the number of connected devices and transmission of the RS485 bus is affected by many factors, far from reaching this value. Usually, only about 30 devices can be connected, and the distance is about 200 meters. These factors include cable shielding performance, cable current capacity, transmission baud rate, cable impedance matching, and the influence of the step-by-step attenuation of the power supply.

[0007] In the process of research and practice of the prior art, the inventor found that among the above factors, the gradual attenuation of the power supply often becomes the biggest bottleneck for the number of connected static levels and the transmission distance. Generally speaking, the power consumption of a single static level in normal working mode is close to 1 watt, so the total power consumption of one hundred static levels will reach 80~100 watts. The system usually uses 24V DC power supply. As the power supply voltage on the cable gradually decays, the power supply voltage of the static level at a certain node will decay to about 9V. Since the power supply range of the static level is 9V~24V, all static levels after this node will not work. We use the average value method to easily deduce that the average voltage of the static level that can work in the entire system is about 16.5 volts. Assuming that the power consumption of each static level is 1 watt, and a total of 100 static levels are mounted, the calculation can be obtained: 1W÷16.5V×100≈6A, that is, the equivalent average current of the entire bus is about 6 amps. Such a large average current will cause a significant voltage attenuation on cables of several hundred meters to thousands of meters in actual engineering application scenarios, causing the voltage of all subsequent nodes on cables longer than several hundred meters to decay to far below 9V, which is lower than the minimum operating voltage of the hydrostatic level. Summary of the invention

[0008] The invention aims to solve the problem that in the existing static leveling measurement system, the power supply voltage of the entire RS485 cable is gradually attenuated, resulting in a small number of connected measuring points and limited communication distance.

[0009] The present invention proposes a method for realizing grouped sleep and wake-up of static levels in a time slice polling manner, and groups all static levels mounted on an RS485 bus. The number of static levels in each group is the same, and it is assumed here that there are N groups in total.

[0010] The system divides the acquisition cycle into N time slices in order. In each time slice, only one group of static levels is activated, so that the static levels in other groups are in sleep standby mode. After completing the measurement data acquisition of all static levels in the group within this time slice, the system automatically sets all static levels in this group to sleep standby mode. In the next time slice, the static levels in the next group are activated as a whole to complete the data acquisition of the next group. This cycle repeats itself, and the data acquisition of the static levels in all N groups is completed in sequence according to the time slices during the entire acquisition cycle. In this way, the peak total power consumption of the system will be reduced to 1 / N of the original, thereby achieving the purpose of greatly increasing the number of connectable static levels and greatly expanding the communication distance.

[0011] To solve the above technical problems, the embodiments of the present invention are implemented through the following technical solutions: After the static level is powered on, it automatically enters the dormant state. The data collector sends a wake-up address through the RS485 bus. The static level that matches the wake-up address will be awakened and start working to provide measurement data collection. After completing the business, it will re-enter the dormant state through the control command sent by the data collector.

[0012] For easy understanding and management, we can regard the wake-up address as a "group address" and group some static levels into a group. The group uses a unified wake-up address, and static levels in different groups are set with different wake-up addresses. The static levels in the group are woken up together, and static levels in different groups are woken up in turn by time slice polling.

[0013] Usually, a 7-bit wake-up address can be set, and the 7-bit wake-up address can support a total of 128 groups. Assuming that each group is mounted with 30 static level gauges, and the system is mounted with a total of 128×30=3840 static level gauges, the system peak power consumption is the same as 30 static levels.

[0014] The following is a detailed description of the sleep standby method of the static level: Usually, a static level is divided into three parts: a power supply unit, a central processing unit, and a sensor measurement unit.

[0015] The method for waking up the central processing unit from sleep mode: The invention completes the waking up of the central processing unit from sleep mode by selecting a single-chip microcomputer with the function of waking up from sleep mode and address. In the sleep mode, the UART port of the single-chip microcomputer can still receive the wake-up address, and the wake-up address is compared with the preset address. If they are equal, the single-chip microcomputer will recover from the sleep mode to the working mode.

[0016] The sleep wake-up method of the sensor measurement unit: the IO pin of the central processing unit is driven by a transistor, and the G level of the PMOS field effect tube is controlled to control the output of the IO pin to be high or low, thereby controlling the opening and closing of the power supply of the sensor measurement unit, turning off the power supply before the central processing unit enters sleep mode, and turning on the power supply after the central processing unit is activated. In this way, the sensor measurement unit does not consume any current when it is in a sleep state at a static level.

[0017] Through the above method, most of the circuits of the static level enter a sleep or power-off state, so that the power consumption level of the static level is reduced from nearly 1 watt to the milliwatt level. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a system topology diagram of the present invention.

[0019] Figure 2 This is a schematic diagram of group sleep and wake-up according to the present invention.

[0020] Figure 3 It is a schematic diagram of the sleep mode and the working mode of the static level of the present invention.

[0021] Figure 4 This is a flow chart of the method provided in Example 1 of the present invention.

[0022] Figure 5 This is a flow chart of the method provided in Example 2 of the present invention.

[0023] Figure 6 This is a flow chart of the method provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0024] In order to make the technical solution of the present invention more clear, the following embodiment 1 is listed for detailed description: Example 1 introduces an implementation step of making the static level meter sleep and wake up in groups by time slice polling, so as to achieve the purpose of greatly increasing the number of connectable static level meters and greatly extending the communication distance. Figure 4 , which is a flow chart of a method provided in Example 1 of the present invention, comprising: S101: The data collector is powered on and starts, supplying power to all subordinate static level instruments through RS485 cables; S102: The static level is powered on and starts up. After starting up, it enters the sleep mode by default; S103: When the sampling period arrives, the collector divides the sampling period into N segments, where N is the same as the number of groups of the static level; S104: the data collector sends a first group wake-up address through the RS485 bus in the first time slice, and all the static level instruments in the first group are awakened; S105: The data collector completes data collection of all the static level instruments in this group through the RS485 bus; S106: After the acquisition is completed, the acquisition instrument sends a sleep command to set all the static levels of this group to enter the sleep standby mode; S107: the data collector completes the awakening and data collection of all the static levels in the next group in the next time slice, and resets all the static levels in this group to enter the sleep standby mode; S108: Repeat the above steps until the data collector obtains the measurement data of all grouped static levels.

[0025] Example 2 introduces a method for implementing the dormancy of a static level instrument, see Figure 5 , which is a flow chart of a method provided in Embodiment 2 of the present invention, comprising: When the static level is powered on, or when the central processing unit of the static level receives a sleep command from the data collector, the process of the static level going into sleep mode is as follows: S201: The central processing unit turns off the PMOS tube through the IO pin control, and turns off the power supply of the sensor measurement unit; S202: The central processing unit closes all I / O ports through software control to minimize power consumption; S203: The central processing unit is instructed to enter a sleep mode.

[0026] Example 3 introduces the method for realizing the awakening of the static level, see Figure 6 , which is a flow chart of a method provided in Embodiment 3 of the present invention, comprising: S301: The UART port of the central processing unit receives a wake-up address from the RS485 bus; S302: If the wake-up address is equal to the self-wake-up address, the central processing unit is activated and enters the working mode; S303: The central processing unit turns on the PMOS tube through the IO pin control, and turns on the power supply of the sensor measurement unit; S304: The central processing unit opens the required I / O port through software control.

Claims

1. A method for realizing group sleep and wake-up of a static level instrument by time slice polling, characterized in that The following steps are involved: S1. After the static level is powered on and started, it automatically enters the sleep state; S2. Group all the static level gauges mounted on the RS485 bus. Here, it is assumed that there are N groups in total. S3, the collector divides the sampling period into N segments, where N is the same as the number of groups of the static level; S4. In the first time slice, the data collector sends the first group wake-up address through the RS485 bus, and all the static levels in the first group are awakened. The static levels in other groups remain in sleep mode. S5, the data acquisition instrument completes the data acquisition of all the static level instruments in the first group through the RS485 bus; S6. After the data collection of this group is completed, the data collector sends a sleep command to set all the static levels of this group to enter the sleep standby mode; S7, the collector completes the wake-up and data collection of all the static levels in the next group in the next time slice, and resets all the static levels in this group to enter the sleep standby mode; S8. This cycle is repeated over and over again, and the data collection of the static level instruments in all N groups is completed in turn according to the time slice polling in the entire collection cycle.

2. The method for realizing group sleep and wake-up of a static level instrument by a time slice polling method according to claim 1, characterized in that: In step S1, the sleep and wake-up of the central processing unit are completed by selecting a single-chip microcomputer with sleep and address wake-up functions.

3. The method for realizing group sleep and wake-up of a static level instrument by a time slice polling method according to claim 1, characterized in that: In step S1, in the sleep state, the central processing unit only keeps the UART port in the activated state, the central processing unit enters the sleep state, and closes all I / O ports. At this time, the energy consumption of the central processing unit is reduced to the minimum. At this time, the central processing unit can still receive the wake-up address sent by the detection and acquisition instrument through the RS485 bus in real time.

4. The method for realizing group sleep and wake-up of a static level instrument by a time slice polling method according to claim 1, characterized in that: In step S1, the I / O pin of the central processing unit is driven by a transistor to control the G level of the PMOS field effect tube, and the I / O pin is controlled to output a low level, thereby turning off the power supply of the sensor measurement unit. In this way, when the static level is in a dormant state, the sensor measurement unit does not consume any current.

5. The method for realizing group sleep and wake-up of a static level instrument by a time slice polling method according to claim 1, characterized in that: In step S4, the static level is in sleep mode, and the UART port of the central processing unit receives and detects the wake-up address on the RS485 bus, and compares the wake-up address with the preset address. If they are equal, the central processing unit will recover from the sleep mode to the working mode; if they are not equal, the central processing unit remains in sleep mode.

6. The method for realizing group sleep and wake-up of a static level instrument by a time slice polling method according to claim 1, characterized in that: In step S4, the static level uses the I / O pin of the central processing unit to control the G level of the PMOS field effect tube after being driven by a transistor, and controls this I / O pin to output a high level, thereby turning on the power supply of the sensor measurement unit, so that the sensor measurement unit of this static level can work normally.

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