CN105620060A

CN105620060A - Printer control circuit

Info

Publication number: CN105620060A
Application number: CN201510955532.5A
Authority: CN
Inventors: 李登峰; 王刚; 张保威; 李诗然; 杨可标; 卢星星; 胡平; 杜浩维; 王玉波; 徐永立; 王雷鸣; 徐雪洁
Original assignee: Changan University
Current assignee: Changan University
Priority date: 2015-12-17
Filing date: 2015-12-17
Publication date: 2016-06-01

Abstract

The invention discloses a printer control circuit. The printer control circuit comprises a thermal printer core and a controller, wherein a power supply module, a single chip microcomputer, a character library memory and a step motor drive circuit are arranged in the controller. According to the printer control circuit, control characteristics of the printer control circuit are increased when some advantages of the conventional thermal printer are continued. The printer control circuit based on STM32 takes an STM32F103C8 single chip microcomputer as the controller, and takes the memory, a step motor and a thermal printing head as control objects; an upper computer and the single chip microcomputer carry out serial port communication, and a serial port testing software is used for sending orders and characters, so that the corresponding characters can be directly printed on thermal paper. According to the test, the printer control circuit is stable and reliable, and the printed handwriting is clear; and both English and Chinese characters can be printed, and bar codes and two-dimensional codes also can be printed.

Description

A kind of printer control circuit

Technical field

The invention belongs to industrial automation, relate to the coding code fetch of English, Chinese character, bar code and Quick Response Code, be specifically related to a kind of minitype thermal printer electric machine control system.

Background technology

At present, the most cost of thermal printer on market is all significantly high, and volume is also relatively big, can not meet the requirement that a lot of device requirement printer is small and exquisite and cost is low, and the printer control circuit therefore designing a kind of low cost necessitates. Simultaneously, on market, existing thermal printer is merely able to print English, Chinese character mostly, part can type slug shape code, development along with the epoch, Quick Response Code application in life is more and more higher, therefore design one can with ordinary symbol and printing bar code, and the thermal printer that can print in the way of Quick Response Code again necessitates.

Summary of the invention

It is an object of the invention to solve above-mentioned problem of the prior art, there is provided that a kind of cost is low, volume is little, print clear, stable minitype thermal printer electric machine control system, this thermal printer can print English, Chinese character, bar code and Quick Response Code, and line space can be set, select alignment pattern, the left side is set from, printable character overstriking selects and high power width selects again. For ease of the printer module of development and product support different vendor newly developed on market, instruction used by this set control system and each manufacturer is compatible, therefore without upgrading software and replaceable corresponding assembly keeps in repair.

To achieve the above object, the technical solution adopted in the present invention is:

A kind of printer control circuit, including thermal printer cassette and controller, is provided with power module, single-chip microcomputer, character library memorizer in controller; Single-chip microcomputer is also associated with telecommunication circuit and for providing the crystal oscillating circuit of clock to single-chip microcomputer; The control interface of single-chip microcomputer is connected to the stepper motor driving circuit for driving printhead paper feed; The external 12V voltage source of power module, single-chip microcomputer, character library memorizer and telecommunication circuit are all connected with the 3.3V voltage output end of power module; Stepper motor driving circuit, thermal printing power supply circuits are connected with the 7.6V of power module.

Being connected to the encryption chip circuit for protecting system program on the control interface of described single-chip microcomputer, encryption chip circuit is connected with the 3.3V voltage output end of power module.

Described encryption chip circuit adopts 12C bus mode to be driven.

Described power module adopts TD7580 blood pressure lowering and AMS1117-3.3 voltage stabilizing chip.

Described character library memorizer adopts GT32L32M0180 word-base chip, and itself and single-chip microcomputer adopt SPI mode to carry out data interaction.

Described telecommunication circuit adopts serial ports to turn usb communication circuit.

Described single-chip microcomputer adopts STM32F103C8 single-chip microcomputer.

Described stepper motor driving circuit adopts LB1838 driving chip, and printhead is connected to overheating protection circuit, it is prevented that temperature is too high burns printhead.

Compared with prior art, the method have the advantages that

The control characteristic of oneself is added while some advantages that the present invention has continued conventional thermal printer. Consider that thermal printer data input and output need a spi bus, character library memorizer needs a spi bus, step motor drive needs four road PWM, between printer and host computer, communication needs a road USART, and the STM32F103C8 single-chip microcomputer that native system is selected contains 64KBFlash, 20KBSRAM, 2 12 ADC, three general 16 bit timing devices, a PWM intervalometer, two SPI, two USART, function complies fully with the needs of this control system, and it is cheap, and this is the big advantage of one. Secondly, native system adopts standard Chinese character word-base chip GT32L32M0180. This word-base chip is a 12x12,16x16,24x24,32x32 dot matrix word library chip that has, and supports GB18030 GB Chinese character, ascii character and bar code picture library, and its character library is completely huge. 3rd, native system is added with printhead overheating protection circuit, it is prevented that temperature overheating burns printhead.

Accompanying drawing explanation

Fig. 1 is the hardware structure diagram that the present invention controls system;

Fig. 2-1 turns the circuit diagram of 7.6V printer power supply for system 12V;

Fig. 2-2 is the circuit diagram of system 3.3V power supply;

Fig. 3 is the circuit diagram that the present invention controls system STM32F103C8 single-chip microcomputer;

Fig. 4 is the serial communication interface circuit diagram that the present invention controls system;

Fig. 5 is the character library storage circuit diagram that the present invention controls system;

Fig. 6 is the encryption chip circuit diagram that the present invention controls system;

Fig. 7 is the stepper motor driving circuit figure that the present invention controls system;

Fig. 8-1 is printer core port circuit figure;

Fig. 8-2 is overheating protection circuit figure.

Detailed description of the invention:

Below in conjunction with accompanying drawing, the present invention is described in further detail:

Referring to Fig. 1 to Fig. 4, the present invention adopts STM32F103C8 single-chip microcomputer as controller, and the module mutual with single-chip microcomputer has character library storage circuit, serial communication circuit, stepper motor driving circuit and the encryption chip circuit to system program encryption. If Fig. 2-1 is to shown in 2-2, the input of power module is connected with outside 12V voltage source, and input voltage generates 7.6V voltage by blood pressure lowering chip TD7580 and provides power supply for printer core and motor; 7.6V voltage produces the output of 3.3V voltage through blood pressure lowering chip AMS1117-3.3, and is connected with single chip circuit, character library storage circuit, telecommunication circuit and encryption chip circuit.

As it is shown in figure 5, character library storage circuit adopts SPI mode and single-chip microcomputer to carry out data exchange; As shown in Figure 6, encryption chip circuit adopts I2C bus mode to be driven, and effect is in that protection system program is not easily cracked; As it is shown in fig. 7, printer stepper motor driving circuit uses LB1828 driving chip, often adding a pulse, paper feed motor just takes a step forward.

As shown in Figure 8, thermal printing head interface circuit is mainly made up of scarce paper signal detection, computer heating control and overheating protection circuit, stepper motor driving circuit etc. As shown in Fig. 8-1, the detection lacking paper signal is realized by the light-sensitive device being integrated within printhead, and CPU is undertaken lacking paper detection by the printhead port PHK low and high level signal sent; Measuring of printhead temperature is obtained by the partial pressure value TM of the internal negative tempperature coefficient thermistor of detection print machine with external resistance, and its magnitude of voltage raises with the temperature of critesistor and reduces; As Fig. 8-2 show overheating protection circuit, when print temperature rises to ultimate value, TM terminal voltage will be less than the reference voltage of comparator inverting input, now comparator output low level, after CPU receives signal, cuts off printer power supply, space suppression.

The present invention can turn USB circuit by serial ports and communicate with host computer, and what host computer adopted is COM Debug Assistant, and during printing, the corresponding order of input and the character to print can print on thermal printing paper.

The present invention relates to the coding of English, Chinese character, bar code and Quick Response Code and code fetch. What adopt due to thermal printer is that the form of character pattern prints, it is therefore desirable to obtain the dot array data of various character. In native system, the character pattern of Chinese character is obtained by standard Chinese character word-base chip GT32L32M0180, and English, bar code, Quick Response Code are all then the lattice informations being obtained respective symbols by program coding.

Above content is only the technological thought that the present invention is described; protection scope of the present invention can not be limited with this; every technological thought proposed according to the present invention, any change done on technical scheme basis, each fall within the protection domain of claims of the present invention.

Claims

1. a printer control circuit, it is characterised in that: include thermal printer cassette and controller, in controller, be provided with power module and single-chip microcomputer, and the character library interacted with single-chip microcomputer stores circuit; Single-chip microcomputer is also associated with telecommunication circuit and for providing the crystal oscillating circuit of clock to single-chip microcomputer; The control interface of single-chip microcomputer is connected to the stepper motor driving circuit for driving printhead paper feed; The external 12V voltage source of power module, stepper motor driving circuit is connected with the 7.6V voltage output end of power module with thermal printer cassette; Single-chip microcomputer, character library storage circuit and telecommunication circuit are connected with the 3.3V voltage output end of power module.

2. printer control circuit according to claim 1, it is characterised in that: being connected to the encryption chip circuit for protecting system program on the control interface of described single-chip microcomputer, encryption chip circuit is connected with the 3.3V voltage output end of power module.

3. printer control circuit according to claim 2, it is characterised in that: described encryption chip circuit adopts 12C bus mode to be driven.

4. the printer control circuit according to claim 1 or 2 or 3, it is characterised in that: described power module adopts TD7580 and AMS117-3.3 blood pressure lowering chip.

5. the printer control circuit according to claim 1 or 2 or 3, it is characterised in that: described stepper motor driving circuit adopts LB1838 to drive.

6. the printer control circuit according to claim 1 or 2 or 3, it is characterised in that: described telecommunication circuit adopts serial ports to turn usb communication circuit.

7. the printer control circuit according to claim 1 or 2 or 3, it is characterised in that: described single-chip microcomputer adopts STM32F103C8 single-chip microcomputer.

8. the printer control circuit according to claim 1 or 2 or 3, it is characterised in that: described thermal printer cassette adopts JX-700-48, carries the critesistor of paper-out detection device and negative temperature coefficient, and be integrated with a bipolar two-phase motor inside it.