CN106444552A - Multi-path quantitative weighing control instrument circuit and control method thereof - Google Patents

Abstract

The invention discloses a multi-channel quantitative weighing control instrument circuit, including a multi-channel output isolation type DC/DC conversion module, an ARM embedded system, a multi-channel AD sampling module, an 8-channel digital isolation input module, and a 20-channel digital isolation output module. Module, RS232/RS485 communication module, the ARM embedded system is respectively connected with multi-channel output isolated DC/DC conversion module, multi-channel AD sampling module, 8-way digital isolation input module, 20-way digital isolation output module and RS232/ RS485 communication module, multi-channel output isolation type DC/DC conversion module is also connected with multi-channel AD sampling module and RS232/RS485 communication module, a kind of multi-channel quantitative weighing control instrument circuit of the present invention can improve the integration of weighing control instrument , stability and system consistency, while reducing the cost of system composition. The invention also discloses a control method for the control instrument circuit.

Description

A multi-channel quantitative weighing control instrument circuit and its control method

technical field

The invention relates to a weighing control instrument, more specifically, to a multi-channel quantitative weighing control instrument circuit; the invention also relates to a control method of the control instrument circuit.

Background technique

At present, the control speed and precision of single-channel/dual-channel weighing control instruments on the market are very good, and they have become very popular. However, in some cases where the packaging tasks are heavy and the time is tight, multiple instruments and multiple machines need to work at the same time to complete. At this time, the parameters of each instrument are not uniform, the networking is complicated, there are disadvantages such as poor stability, cumbersome operation, and low system integration. high. Therefore, it is urgent to invent a control device capable of simultaneously controlling multiple instruments.

Contents of the invention

The purpose of the present invention is to provide a multi-channel quantitative weighing control instrument circuit, the weighing control instrument circuit can improve the integration, stability and system consistency of the weighing control instrument, while reducing the cost of system composition.

Another object of the present invention is to provide a control method for a circuit of a multi-channel quantitative weighing control instrument, which can realize the functions of a traditional weighing control instrument.

The preceding technical scheme that the present invention adopts is as follows:

A multi-channel quantitative weighing control instrument circuit, which includes a multi-channel output isolated DC/DC conversion module, an ARM embedded system, a multi-channel AD sampling module, an 8-channel digital isolation input module, a 20-channel digital isolation output module, RS232/RS485 communication module, the ARM embedded system is respectively connected with multi-channel output isolated DC/DC conversion module, multi-channel AD sampling module, 8-channel digital isolation input module, 20-channel digital isolation output module and RS232/RS485 communication module, the multi-channel output isolated DC/DC conversion module is also connected to a multi-channel AD sampling module and an RS232/RS485 communication module, and the signal input terminal of the multi-channel AD sampling module is connected to the signal output of a plurality of external load cells end.

The latter technical scheme that the present invention adopts is as follows:

A control method for a multi-channel quantitative weighing control instrument circuit, comprising the following control steps:

(1) The multi-channel output isolation type DC/DC conversion module converts the input voltage to each module, and the ARM processor of the ARM embedded system is powered on and resets;

(2) described ARM processor initializes the chip port, then configures the multi-channel AD sampling module after reading the saved parameters from the power-down memory module, and then configures the external interrupt detection ADC conversion of the ARM processor to complete;

(3) the ADC data reading interrupt of the ARM processor is placed in the highest priority, and the serial port reception interrupt of the ARM processor is placed in the secondary priority, waiting to receive ADC data or serial port data;

(4) When the ARM processor received the ADC interrupt, the ARM processor read the AD data of 6 slices of CS5532 in the multi-channel AD sampling module in order, and separated the 8-way digital isolation input module and the 20-way The data of the digital isolation output module is updated; the ARM processor analyzes the weight signal to determine whether the sensor is in a stable state. When the weighing weight of the external load cell is equal to the tare weight and is stable, it is changed to the start output output flag. When the external load cell When the weighed weight is greater than or equal to the set weight, it will be changed to stop the discharge output flag, and the interrupt will return;

(5) When the ARM processor received the serial port data interrupt, the RS232/RS485 communication module converted the level on the RS232 or RS485 bus into the level received by the ARM processor, and the ARM processor Transform the received data according to the received level, switch to the corresponding level through the RS232/RS485 communication module (8) to the corresponding data line, and interrupt the return;

(6) Scan the matrix keyboard module, update the LCD display module, and jump to step (3).

Compared with prior art, the beneficial effect that the present invention has is:

1. A multi-channel quantitative weighing control instrument circuit of the present invention includes a multi-channel output isolation type DC/DC conversion module, an ARM embedded system, a multi-channel AD sampling module, an 8-channel digital isolation input module, and a 20-channel digital isolation Output module, RS232/RS485 communication module, the ARM embedded system is respectively connected with multi-channel output isolated DC/DC conversion module, multi-channel AD sampling module, 8-channel digital isolation input module, 20-channel digital isolation output module and RS232 /RS485 communication module, the multi-channel output isolated DC/DC conversion module is also connected to the multi-channel AD sampling module and RS232/RS485 communication module, and the signal input terminal of the multi-channel AD sampling module is connected to the signal output terminals of multiple external weighing sensors. Through modular program design, it is equivalent to one weighing control instrument instead of six weighing control instruments on the market. The weighing control instrument circuit can improve the integration, stability and system consistency of the weighing control instrument. , while reducing the cost of system composition.

2. The control method of a kind of multi-channel quantitative weighing control instrument circuit of the present invention, multi-channel output isolation type DC/DC conversion module converts input voltage to each module, and the ARM processor of described ARM embedded system is powered on and resets; The ARM processor initializes the chip port, then configures the multi-channel AD sampling module after reading the saved parameters from the power-down memory module, and then configures the external interrupt detection ADC conversion of the ARM processor to complete; the ARM processor's ADC data reading interrupt is placed in the highest priority, the serial port receiving interrupt of the ARM processor is placed in the secondary priority, waiting to receive ADC data or serial port data, and then perform corresponding operations according to the obtained ADC data or serial port data, and scan all The matrix keyboard module described above jumps to wait for the interrupt signal cycle after updating the LCD display module. Using this control method, the functions realized by six weighing control instruments on the market can be realized.

Description of drawings

Fig. 1 is a schematic diagram of the present invention;

Fig. 2 is a schematic circuit diagram of a multi-channel output isolated DC/DC conversion module of the present invention;

Fig. 3 is the circuit schematic diagram of ARM embedded system of the present invention;

Fig. 4 is the circuit schematic diagram of 8-way digital isolation input module and RS232/RS485 communication module of the present invention;

Fig. 5 is the circuit schematic diagram of multi-channel AD sampling module of the present invention;

Fig. 6 is the circuit principle diagram of single AD sampling module of the present invention;

Fig. 7 is the schematic circuit diagram of the 20-way digital isolation output module of the present invention;

Fig. 8 is the connection diagram of ARM embedded system of the present invention;

Fig. 9 is a control flowchart of the control instrument circuit of the present invention.

detailed description

The technical solutions of the present invention will be further described in detail below in conjunction with specific embodiments, but this does not constitute any limitation to the present invention.

As shown in Figures 1 to 8, a multi-channel quantitative weighing control instrument circuit of the present invention includes a multi-channel output isolated DC/DC conversion module 1, an ARM embedded system 2, a multi-channel AD sampling module 3, 8-way digital isolation input module 4, 20-way digital isolation output module 5, RS232/RS485 communication module 8, the ARM embedded system 2 is respectively connected to the multi-channel output isolated DC/DC conversion module 1, and the multi-channel AD sampling module 3. 8-way digital isolation input module 4, 20-way digital isolation output module 5 and RS232/RS485 communication module 8. The multi-channel output isolation type DC/DC conversion module 1 is also connected to multi-channel AD sampling module 3 and RS232/RS485 communication module 8. RS485 communication module 8, the signal input end of the multi-channel AD sampling module 3 is connected to the signal output ends of a plurality of external weighing sensors. Realize equivalent to a kind of multi-channel quantitative weighing control instrument circuit of the present invention to replace the function realized by using 6 weighing control instruments on the market through modularized program design, this weighing control instrument circuit can improve the weighing control instrument Integration, stability and system consistency, while reducing the cost of system composition.

The input end of the multi-channel output isolation type DC/DC conversion module 1 is connected to an input voltage, and the output end of the multi-channel output isolation type DC/DC conversion module 1 is respectively connected to the ARM embedded system 2, the multi-channel AD sampling Module 3 and RS232/RS485 communication module 8, the output end of the multi-output isolated DC/DC conversion module 1 is also connected to a plurality of external load cells. Among them, the input terminal of the multi-channel output isolated DC/DC conversion module 1 is connected to the 24V DC input voltage, and the multi-channel output isolated DC/DC conversion module 1 simultaneously supplies the ARM embedded system 2, the multi-channel AD sampling module 3 and the RS232 /RS485 communication module 8 and multiple external load cells are powered.

Described ARM embedded system 2 comprises ARM processor 6, matrix keyboard module 7, power down memory module 9 and LCD display module 10, and described ARM processor 6 connects matrix keyboard module 7, power down memory module 9, LCD display module 10.

Described multi-channel AD sampling module 3 comprises 6 CS5532 analog-to-digital conversion chips, the SCLK pins of each CS5532 analog-to-digital conversion chip are connected in parallel, and the SDI pins of each CS5532 analog-to-digital conversion chip are connected in parallel, The SDO pins of each CS5532 analog-to-digital conversion chip are connected in parallel, and the OCS2 pins of each CS5532 analog-to-digital conversion chip are connected in parallel and connected with a 4.9152MHz active crystal oscillator. The SCLK pin, SDI pin, and SDO pin of the CS5532 analog-to-digital conversion chip are connected to the pin of the SPI3 of the ARM processor 6 through a magnetic coupling isolator, and the CS pins of each CS5532 analog-to-digital conversion chip are respectively Connect with PG10 pin to PG15 pin of ARM processor 6. Synchronous sampling of multiple channels is realized by integrating 6 pieces of CS5532 analog-to-digital converters, and the sampling accuracy and speed of each channel are the same as those of single-channel weighing instruments.

Described 8-way digital isolation input module 4 comprises 2 slices of TLP281-4 optocouplers, and the collector output pins of 2 slices of TLP281-4 optocouplers are connected with PA7 pins, PB0 pins, PB1 pins of ARM processor 6 respectively. Pin, PB2 pin, PC4 pin, PC5 pin, PF11 pin, PF12 pin connection. Two TLP281-4 optocouplers described above isolate the signal of the ARM processor 6 from the external input signal.

The 20-way digital isolation output module 5 includes an isolated external coil drive circuit composed of 5 TLP281-4 optocouplers and 3 ULN2803 Darlington tube arrays, and the cathode input leads of the 5 TLP281-4 optocouplers The pins are respectively connected with the PD8 pins, PD9 pins, PD10 pins, PD11 pins, PD12 pins, PD13 pins, PD14 pins, PD15 pins, PE7 pins, PE8 pins, and PE9 pins of the ARM processor 6. Pin, PE10 pin, PE11 pin, PE12 pin, PE13 pin, PF13 pin, PF14 pin, PF15 pin, PG0 pin, PG1 pin connection.

Described RS232/RS485 communication module 8 comprises RS232 communication circuit and RS485 communication circuit, and described RS232 communication circuit is connected with USART1 pin of ARM processor 6 by a magnetic coupler ADuM1402, and described RS485 communication circuit is connected with by a magnetic coupler ADuM1402 USART2 pin connection of ARM processor 6.

Described ARM processor 6 comprises STM32F103ZET6 chip; Described matrix keyboard module 7 is connected with PC10 pin, PC11 pin, PC12 pin, PD0 pin, PD1 pin, PD2 pin of ARM processor 6 respectively , PD3 pin, PD4 pin, PD5 pin connection.

The power-down memory module 9 includes an FM25CL64 chip, and the FM25CL64 chip is connected to the SPI2 pin of the ARM processor 6 .

Described LCD display module 10 comprises the LCD12864 liquid crystal display that adopts ST7290 drive, and the SID pin of described LCD12864 liquid crystal display is connected with the TX pin of USART3 of ARM processor 6, and the SCK pin of described LCD12864 liquid crystal display is connected with ARM processing connected to the CK pin of USART3 of device 6.

As shown in Figure 9, a control method for a multi-channel quantitative weighing control instrument circuit according to the present invention includes the following control steps:

(1) The multiple output isolated DC/DC conversion module 1 converts the input voltage to each module, and the ARM processor 6 of the ARM embedded system 2 is powered on and reset.

(2) The ARM processor 6 initializes the chip port, then configures the multi-channel AD sampling module 3 after reading the saved parameters from the power-down memory module 9, and then configures the external interrupt detection ADC conversion of the ARM processor 6 to complete.

(3) Place the ADC data reading interrupt of the ARM processor 6 at the highest priority, place the serial port receiving interrupt of the ARM processor 6 at the secondary priority, and wait for receiving ADC data or serial port data.

(4) When the ARM processor 6 received the ADC interrupt, the ARM processor 6 had read the AD data of 6 slices of CS5532 in the multi-channel AD sampling module 3 in order, and the 8-way digital isolation input module 4 and 20-channel digital isolation output module 5 data update, to ensure that the port update time intervals of 8-channel digital isolation input module 4 and 20-channel digital isolation output module 5 are consistent and not affected by other interruptions. Because there is no conditional jump statement when reading AD data, the time from interrupt to completion of reading data is fixed. Carry out sliding average digital filtering on the AD data, and then perform engineering unit conversion. The ARM processor 6 analyzes the weight signal to determine whether the sensor is in a stable state, and improves the control signal for subsequent weighing process control. When the weighing weight of the external load cell is equal to the tare weight and is stable, it will be changed to start the output output flag, and when the external load cell is greater than or equal to the set weight, it will be changed to the stop output output flag, which is the next time Prepare for port update, after which interrupt returns.

(5) When the ARM processor 6 received the serial port data interrupt, the RS232/RS485 communication module 8 converted the level on the RS232 or RS485 bus into the level received by the ARM processor 6, and the The ARM processor 6 transforms the received data according to the received level, and switches to the corresponding level through the RS232/RS485 communication module 8 to the corresponding data line, and then interrupts and returns.

(6) Scan the matrix keyboard module 7, update the LCD display module 10, and jump to step 3.

The above descriptions are only preferred embodiments of the present invention, and any modifications, equivalent replacements and improvements made within the spirit and scope of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. a kind of Multi-path proportional Weighing control appliance circuit is it is characterised in that include multiple-channel output isolated form DC/DC conversion module (1), ARM embedded system (2), multi-channel A/D sampling module (3), 8 railway digitals isolation input module (4), 20 railway digital isolation are defeated Go out module (5), RS232/RS485 communication module (8), described ARM embedded system (2) connects multiple-channel output isolated form respectively DC/DC conversion module (1), multi-channel A/D sampling module (3), 8 railway digitals isolation input module (4), 20 railway digital isolation and amplifier moulds Block (5) and RS232/RS485 communication module (8), described multiple-channel output isolated form DC/DC conversion module (1) is also connected with multichannel AD sampling module (3) and RS232/RS485 communication module (8), the signal input part connection of described multi-channel A/D sampling module (3) is many The signal output part of individual outside LOAD CELLS.

2. a kind of Multi-path proportional Weighing control appliance circuit according to right 1 is it is characterised in that described multiple-channel output is isolated The input of type DC/DC conversion module (1) is connected with an input voltage, described multiple-channel output isolated form DC/DC conversion module (1) Outfan connect ARM embedded system (2), multi-channel A/D sampling module (3) and RS232/RS485 communication module (8), institute respectively The outfan stating multiple-channel output isolated form DC/DC conversion module (1) is also connected with multiple outside LOAD CELLSs.

3. a kind of Multi-path proportional Weighing control appliance circuit according to claim 1 is it is characterised in that described ARM is embedding Embedded system (2) includes arm processor (6), matrix keyboard module (7), power down memory module (9) and LCD display module (10), described arm processor (6) connection matrix Keysheet module (7), power down memory module (9), LCD display module respectively (10).

4. a kind of Multi-path proportional Weighing control appliance circuit according to claim 2 is it is characterised in that described multi-channel A/D Sampling module (3) includes 6 CS5532 modulus conversion chips, the SCLK pins in parallel of every described CS5532 modulus conversion chip Connect, the SDI pins in parallel of every described CS5532 modulus conversion chip connects, every described CS5532 modulus conversion chip SDO pins in parallel connects, and the OCS2 pins in parallel of every described CS5532 modulus conversion chip connects and with a 4.9152MHz's Active crystal agitator connects, every the SCLK pin of described CS5532 modulus conversion chip being connected in parallel, SDI pin, SDO Pin is connected with the pin of the SPI3 of arm processor (6) by a magnetic coupled isolator, every described CS5532 analog digital conversion core The CS pin of piece is connected to PG15 pin with the PG10 pin of arm processor (6) respectively.

5. a kind of Multi-path proportional Weighing control appliance circuit according to claim 1 is it is characterised in that described 8 ways Word isolation input module (4) includes 2 TLP281-4 optocouplers, and the colelctor electrode output pin of 2 described TLP281-4 optocouplers is respectively With the PA7 pin of arm processor (6), PB0 pin, PB1 pin, PB2 pin, PC4 pin, PC5 pin, PF11 pin, PF12 Pin connects.

6. a kind of Multi-path proportional Weighing control appliance circuit according to claim 1 is it is characterised in that described 20 ways Word isolation and amplifier module (5) is included outside the isolated form that is made up of 5 TLP281-4 optocouplers and 3 ULN2803 Darlington transistor arrays Portion's coil driver, the negative electrode input pin of 5 described TLP281-4 optocouplers respectively with the PD8 pin of arm processor (6), PD9 pin, PD10 pin, PD11 pin, PD12 pin, PD13 pin, PD14 pin, PD15 pin, PE7 pin, PE8 draw Foot, PE9 pin, PE10 pin, PE11 pin, PE12 pin, PE13 pin, PF13 pin, PF14 pin, PF15 pin, PG0 Pin, PG1 pin connect.

7. a kind of Multi-path proportional Weighing control appliance circuit according to claim 1 is it is characterised in that described RS232/ RS485 communication module (8) includes RS232 telecommunication circuit and RS485 telecommunication circuit, and described RS232 telecommunication circuit passes through a magnetic coupling ADuM1402 is connected with the USART1 pin of arm processor (6), described RS485 telecommunication circuit pass through a magnetic coupling ADuM1402 with The USART2 pin of arm processor (6) connects.

8. a kind of Multi-path proportional Weighing control appliance circuit according to claim 3 is it is characterised in that at described ARM Reason device (6) includes STM32F103ZET6 chip；Described matrix keyboard module (7) is drawn with the PC10 of arm processor (6) respectively Foot, PC11 pin, PC12 pin, PD0 pin, PD1 pin, PD2 pin, PD3 pin, PD4 pin, PD5 pin connect； Described power down memory module (9) includes FM25CL64 chip, described FM25CL64 chip and arm processor (6) SPI2 pin connects.

9. a kind of Multi-path proportional Weighing control appliance circuit according to claim 3 is it is characterised in that described LCD shows Show that module (10) includes the LCD12864 liquid crystal display driving using ST7290, the SID of described LCD12864 liquid crystal display Pin is connected with the TX pin of the USART3 of arm processor (6), at the SCK pin of described LCD12864 liquid crystal display and ARM The CK pin of the USART3 of reason device (6) is connected.

10. a kind of control method of the Multi-path proportional Weighing control appliance circuit described in claim 3 is it is characterised in that include Following rate-determining steps：

(1) to modules, described ARM embeds multiple-channel output isolated form DC/DC conversion module (1) the conversion input voltage described in The arm processor (6) of formula system (2) obtains reset；

(2) arm processor (6) the initialization chip port described in, then from the parameter of power down memory module (9) reading and saving Configuration multi-channel A/D sampling module (3) afterwards, the outer interruption detecting ADC being reconfigured at arm processor (6) converts；

(3) adc data of described arm processor (6) is read interruption and be placed in limit priority, by described arm processor (6) Serial ports receives and interrupts being located at sub-priority, waits adc data to be received or serial data；

(4) when described arm processor (6) receives ADC interruption, described arm processor (6) has read multichannel in order The AD data of 6 CS5532 in AD sampling module (3), by 8 railway digitals isolation input module (4) and 20 railway digital isolation and amplifier moulds Block (5) data updates；To weight signal analysis, arm processor (6) judges whether sensor is in steady statue, when weighing in outside Scales heavy amount changes into beginning discharging output identification position when being equal to tare weight weight and stablizing, when outside LOAD CELLS Weight of weighing changes into stopping discharging output identification position when being more than or equal to setting weight, interrupt returning；

(5) when described arm processor (6) receives serial data and interrupts, described RS232/RS485 communication module (8) Level conversion in RS232 or RS485 bus is become the level that arm processor (6) receives, described arm processor (6) basis The level translation receiving data receiving, is transformed into corresponding level to respective data lines by RS232/RS485 communication module (8) On, interrupt returning；

(6) scan described matrix keyboard module (7), update LCD display module (10), jump to step (3).