Control method of a printing system and printing system
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING BOYUAN HENGXIN TECH CO LTD
- Filing Date
- 2026-03-16
- Publication Date
- 2026-06-16
Smart Images
Figure CN122211080A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of printer data processing and printhead control technology, and more particularly to a control method for a printing system and a printing system. Background Technology
[0002] In the field of printhead control in printing systems, traditional technologies generally adopt a direct control scheme in which each printhead is individually connected to the pin of a microcontroller unit (MCU) to realize operations such as reading and writing information, voltage configuration, and status monitoring of each printhead.
[0003] Traditional solutions require each printhead to be configured with an independent MCU I / O pin for signal transmission and control. This results in the system's MCU I / O pin resource usage increasing exponentially with the number of printheads. This not only significantly limits the range of MCUs that can be selected and increases hardware costs, but also causes many inconveniences for the hardware design, integration, and future expansion of the printing system due to the complex pin layout. It is difficult to meet the industrial printing requirements for hardware miniaturization, low cost, and flexible expansion.
[0004] To address the aforementioned technical problem of excessive IO pin resource consumption, there is an urgent need in this field for a technical solution that can achieve efficient control of multiple nozzles without increasing the number of MCU pins. Summary of the Invention
[0005] The purpose of this invention is to provide a control method and a printing system for a printing system, which solves the technical problem that the existing printing system configures multiple printheads with independent IO pins, resulting in excessive IO pin resource consumption of the MCU.
[0006] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a control method for a printing system, comprising: The microcontroller receives the print data packets sent by the host computer and parses the print data packets to obtain the parsing results; the parsing results include at least the printhead operation instructions, printhead operation type, and target printhead information; Determine the target multiplexer based on the nozzle operation type; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation instructions.
[0007] Optionally, the printed data packet must at least contain a command code; Parsing the printed data packets includes: The command code is extracted from the printed data packet, and the command type is obtained by identifying the command code; the command type includes one of the following: nozzle operation instruction, FPGA register operation instruction, and file system operation instruction.
[0008] Optionally, the target multiplexer is determined based on the nozzle operation type, including: If the nozzle operation type is a control operation, the control multiplexer is identified as the target multiplexer; control operations include at least setting the correction voltage; If the nozzle operation type is a monitoring operation, the monitoring multiplexer is identified as the target multiplexer; monitoring operations include at least temperature reading; the control multiplexer and the monitoring multiplexer share the same set of control pins of the microcontroller unit.
[0009] Optionally, the printed data packet also includes a data payload; Parsing the print data packet also includes: extracting target nozzle information from the data payload; the target nozzle information is either a single-point nozzle number or full-volume nozzle control parameters. Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation commands, including: If the target nozzle information is a single-point nozzle number, the target multiplexer is controlled in fixed-point mode to connect the communication link corresponding to the single-point nozzle number, and the nozzle operation command is sent to the target nozzle so that the target nozzle performs the corresponding action. If the target nozzle information is the full range of nozzle control parameters, the target multiplexer is controlled in polling mode to sequentially activate the communication links corresponding to each nozzle according to a preset timing sequence, and the nozzle operation commands are sent to each nozzle one by one, so that each nozzle executes the corresponding action in sequence.
[0010] Optionally, when the nozzle operation command is to set the correction voltage and the target nozzle information is the full range of nozzle control parameters, based on the target nozzle information, the target multiplexer controls the target nozzle to execute the action corresponding to the nozzle operation command, including: The control multiplexer is controlled in polling mode to sequentially activate the communication link corresponding to each nozzle according to a preset timing sequence and read the operating voltage of each nozzle. The actual correction voltage of each nozzle is calculated by comparing its operating voltage with the corresponding reference correction voltage in the voltage correction table; the voltage correction table is a pre-stored correction table retrieved from the Flash storage medium. The control multiplexer is controlled in polling mode to sequentially activate the communication link corresponding to each nozzle according to a preset timing sequence and set the actual correction voltage of each nozzle.
[0011] Optionally, when the printhead operation instruction is to set the printhead DO output operation, parsing the print data packet also includes: extracting the enable bit, the first status bit, and the GPIO port number from the data payload; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation commands, including: The target multiplexer is controlled to conduct the communication link according to the target nozzle information. If the enable bit is in an active state, the target GPIO port corresponding to the target nozzle is located according to the GPIO port number, and the target GPIO port is set to high or low level according to the instruction of the first state bit. If the enable bit is invalid, the target GPIO port will maintain its original level and no output adjustment operation will be performed.
[0012] Optionally, the printed data packet also includes a response flag; the response flag is used to indicate whether the result needs to be fed back to the host computer. The control method also includes: after controlling the target nozzle to execute the action corresponding to the nozzle operation command through the target multiplexer based on the target nozzle information, feeding back the operation execution result to the host computer based on the response flag; The operation execution result is fed back to the host computer based on the response flag, including: If a response flag indicates that feedback is required, a response data packet is generated and sent to the host computer. The response data packet includes at least the original command code, the response status code, and a timestamp. The original command code is the command code in the printed data packet. The response status code is used to identify the operation execution result. The timestamp records the operation completion time. The operation execution result includes operation success, parameter error, verification failure, board mismatch, and unknown error. If the response flag indicates that no feedback is required, neither a response data packet is generated nor sent.
[0013] Optionally, when the FPGA register operation instruction is to set the ignition direction, parsing the printed data packet also includes: extracting the board type flag and ignition direction parameters from the data payload; Control methods also include: The FPGA register address is determined based on the board type flag. The ignition direction parameter is written to the target register corresponding to the register address. The FPGA reads the ignition direction parameter in the target register and generates the corresponding ignition control signal. The ignition control signal is then sent to the corresponding nozzle to complete the ignition direction setting.
[0014] Compared with existing technologies, the control method of the printing system provided by this invention introduces a multiplexer as a control intermediary between the MCU and multiple printheads, transforming the traditional independent IO pin control mode that is positively correlated with the number of printheads into a fixed-pin multiplexer channel switching mode. By parsing the operation type to match the multiplexer and selecting the channel according to the printhead information, the control logic achieves precise control of multiple printheads, fundamentally solving the problem of excessive IO pin resource occupation in traditional solutions, and significantly improving the overall efficiency of multi-printhead control.
[0015] Specifically, traditional solutions require configuring an independent MCU I / O pin for each nozzle, with pin usage increasing exponentially with the number of nozzles. In contrast, this invention controls a multiplexer using a small number of fixed pins, and the multiplexer then selects the target nozzle channel. This eliminates the need to add I / O pins for new nozzles, freeing up MCU pin resources, expanding the range of MCU options, simplifying hardware layout, and reducing hardware costs and design integration complexity. Simultaneously, through precise matching of operation type and multiplexer, and rapid selection of nozzle information and channels, efficient switching and execution of multi-nozzle control are achieved, enabling precise and efficient control of multiple nozzles without increasing the number of MCU pins.
[0016] In a second aspect, the present invention also provides a printing system, comprising: a host computer, a headboard, and a printhead array; the headboard integrates at least a microcontroller and a multiplexer; The host computer is communicatively connected to the microcontroller unit, and the microcontroller unit is electrically connected to the multiplexer. The microcontroller unit is used to receive print data packets sent by the host computer and parse the print data packets to obtain the parsing results; the parsing results include at least the printhead operation instructions, printhead operation type and target printhead information; Determine the target multiplexer based on the nozzle operation type; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation instructions.
[0017] Optionally, the printing system also includes: a Flash storage medium; the Flash storage medium is electrically connected to the microcontroller unit; The headboard also integrates an FPGA; the FPGA is electrically connected to the microcontroller unit. The multiplexer includes a control multiplexer and a monitoring multiplexer; the control multiplexer and the monitoring multiplexer are connected to all the nozzles in the nozzle array via communication links; the control multiplexer and the monitoring multiplexer share the same set of control pins of the microcontroller unit. Attached Figure Description
[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 A flowchart illustrating a control method for a printing system according to an embodiment of the present invention; Figure 2 A schematic diagram of the structure of a printing system provided in one embodiment of the present invention; Figure 3 This is a partial flowchart illustrating a control method for a printing system provided in one embodiment of the present invention.
[0019] Figure labels: 1-Host computer; 2-Headboard; 3-Nozzle array; 20-Microcontroller unit; 21-FPGA; 22-Control multiplexer; 23-Monitoring multiplexer. Detailed Implementation
[0020] To facilitate a clear description of the technical solutions in the embodiments of the present invention, the terms "first" and "second" are used to distinguish identical or similar items with essentially the same function and effect. For example, the first threshold and the second threshold are merely used to distinguish different thresholds and do not limit their order. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that the terms "first" and "second" are not necessarily different.
[0021] It should be noted that in this invention, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.
[0022] In this invention, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between the associated objects, indicating that three relationships can exist.
[0023] like Figure 1 As shown, this embodiment of the invention provides a control method for a printing system. The printing system used in this method is described in [reference needed]. Figure 2 The system includes at least a host computer 1 and a printhead board 2. The printhead board 2 integrates at least a microcontroller unit 20, an FPGA (Field Programmable Gate Array) 21, a multiplexer, and a printhead array 3. The printhead array 3 is an array composed of multiple printheads. The printhead board 2 also integrates a Flash storage medium. The host computer 1 is communicatively connected to the microcontroller unit 20 and is used to send printing data packets to the microcontroller unit 20. The microcontroller unit 20 is electrically connected to the FPGA 21, the multiplexer, and the Flash storage medium to realize data interaction and hardware control.
[0024] See Figure 1 The control method of this invention may include: Step S1: The microcontroller receives the print data packet sent by the host computer and parses the print data packet to obtain the parsing result; the parsing result includes at least the printhead operation command, printhead operation type and target printhead information; Specifically, a micro control unit (MCU) integrates a central processing unit (CPU), a memory (random access memory, RAM / read only memory, ROM), a general-purpose input / output interface (GPIO), a timer / counter, an analog-to-digital converter (A / D), and other circuit components.
[0025] Step S2: Determine the target multiplexer based on the nozzle operation type; Step S3: Based on the target nozzle information, control the target nozzle to execute the actions corresponding to the nozzle operation instructions through the target multiplexer.
[0026] In existing technologies, configuring an independent MCU I / O pin for each nozzle leads to a doubling of pin resources with the number of nozzles, resulting in problems such as limited MCU selection, increased hardware costs, and poor system scalability. This invention addresses this by uniformly parsing host computer data packets to extract elements such as nozzle operation, operation type, and target nozzle information. This provides clear data for subsequent multiplexer selection and link activation, avoiding redundant hardware pin configurations from the outset. It abandons the traditional direct binding mode between nozzles and MCU pins, determining the target multiplexer based on the nozzle operation type, and then controlling the multiplexer to activate the corresponding link based on the target nozzle information, thus aggregating the control requirements of multiple nozzles onto a small number of multiplexers.
[0027] The multiplexer requires only a small number of MCU I / O pins for gating control, eliminating the need for separate pin configurations for each nozzle. This significantly reduces the number of MCU I / O pins used at the hardware level, enabling switching control of multiple nozzle communication links with a limited number of pins. The MCU can precisely connect and disconnect communication links between different nozzles and the MCU by controlling only a few control pins of the multiplexer, replacing the traditional method of directly controlling each nozzle link through the I / O pins of different MCUs. Furthermore, as the number of nozzles in the system increases, channel switching can be completed using only the existing pins of the multiplexer, without the need to add new MCU I / O pins, completely solving the technical problem of pin resources multiplying with the number of nozzles.
[0028] In summary, this invention, through a control link of "instruction parsing → multiplexer selection → link connection and action execution," uses a multiplexer as an intermediary to transform the IO pin requirements, which are directly related to the number of printheads in traditional solutions, into a fixed number of pin requirements that match the multiplexer. This achieves efficient and precise control of multiple printheads without increasing the number of MCU pins. At the same time, it solves the derivative problems caused by excessive pins, such as limited MCU selection, increased hardware costs, and inconvenient design expansion. It is adapted to the specific needs of industrial printing for hardware miniaturization, low cost, and flexible expansion.
[0029] The following section introduces the format and parsing rules for printing data packets.
[0030] The print data packets sent by the host computer adopt a unified format, which includes command code, data length, response flags, and data payload, specifically: [command code (cmd) + data length (len) + response flags (ret) + data payload (data)]. The definitions of each field are shown in Table 1. Table 1: Standard Format of Data Packets Field Name logo length illustrate command code cmd 1 byte Used to identify specific commands Data length len 2 bytes Indicate the length of subsequent load data Response flags ret 1 byte Indicate whether a response is required and the type of response. Data payload data Length Specific parameters and data content for each command As can be seen from the above, the command code is a unique numerical code corresponding to a specific operation. In practical implementation, the microcontroller unit integrates at least a command parsing module, which can be used to parse printed data packets. By parsing the command code, the command type of the major functional operation category can be obtained.
[0031] Parsing a printed data packet can include: extracting command codes from the printed data packet and identifying the command type by recognizing the command codes. Specifically, identifying the command type by recognizing the command codes involves matching the numerical encoding of the command codes with a preset command type encoding mapping table to identify the specific command type.
[0032] For example, see Figure 3 The command types parsed by the MCU include one of the following: nozzle operation instructions, FPGA register operation instructions, and file system operation instructions, and may also include other types of operation instructions; among them, nozzle operation instructions are used to control the target nozzle to perform corresponding actions or monitor the working status of the target nozzle, and are the core command type.
[0033] The numerical encoding of the command code is exemplified below: 0x01: Nozzle Operation → Voltage Configuration Processing (Control class, used to set the nozzle operating voltage or read the correction voltage); 0x02: Nozzle operation command → Read temperature (used to read nozzle or ambient temperature data); 0x03: Printhead operation command → Set waveform (used to set the printhead inkjet waveform); 0x04: Nozzle operation command → Read status data (used to read the working status of the nozzle, hardware fault status, etc.); 0x10: FPGA register operation instructions (used for FPGA register read / write and timing verification); 0x20: File system operation command → Read file (used to read configuration files from storage media); 0x21: File system operation command → Save configuration (used to write waveform files, voltage correction files, etc. to the Flash storage area); 0x22: File system operation command → Delete file (used to delete invalid configuration files); 0x30: Nozzle operation command (auxiliary hardware control operation command, i.e., DO output, used to control the on / off status of auxiliary hardware such as nozzle cleaning module and heating module); 0xFF: Other system function instructions (used for system-level operations such as system reset and log export).
[0034] This embodiment achieves precise classification of command types through command code parsing, dividing them into major functional categories such as nozzle operation, FPGA register operation, and file system operation. Different functional categories correspond to independent execution paths and hardware adaptation logic, bringing the following benefits: 1) It achieves precise instruction routing and layered processing. Instructions in different functional categories each have their own dedicated execution chain, avoiding system resource contention caused by mixed traffic, ensuring the execution priority and real-time performance of core nozzle operation instructions. Combined with dynamic channel switching technology, it can effectively reduce nozzle switching time from milliseconds to microseconds, significantly improving the overall system response speed; 2) It clarifies nozzle operation commands. With its special status among all command types, the MCU only controls the multiplexer to turn on the corresponding hardware channel when executing nozzle operation commands. During the execution of other instructions, it does not occupy the IO pins and hardware resources related to nozzle control, which greatly reduces the invalid occupation of IO pins and improves the utilization rate of hardware resources. 3) Adopting a standardized instruction architecture with major categories, when adding new function instructions or expanding the number of nozzles, only the corresponding command code and matching execution logic need to be added. The existing data packet parsing and hardware control framework can be directly reused without modifying the underlying hardware design. This supports the system to achieve up to 16 nozzles without hardware modification expansion, fundamentally solving the problem of poor scalability of existing technologies.
[0035] The response flag is used to indicate whether the result needs to be fed back to the host computer; the control method also includes: after controlling the target nozzle to perform the action corresponding to the nozzle operation command through the target multiplexer based on the target nozzle information, feeding back the operation execution result to the host computer based on the response flag.
[0036] The operation execution result is fed back to the host computer based on the response flag, including: if the response flag indicates that feedback is required, generating and sending a response data packet to the host computer. The response data packet includes at least the original command code, the response status code, and a timestamp; the original command code is the command code printed in the data packet, the response status code is used to identify the operation execution result, and the timestamp records the operation completion time; the operation execution result includes operation success, parameter error, verification failure, board mismatch, and unknown error; the response data packet may also include optional additional data, and the definitions of each field in the response data packet are shown in Table 2. Table 2: Response Data Packet Format Field Name illustrate Raw command code cmd, which corresponds to the command code issued, is used to match the response to the corresponding command. Response status code status indicates the command execution result. Additional data extra_data, optional, supplementary information returned based on the operation execution result. For an explanation of the response status codes, please refer to Table 3.
[0037] Table 3: Examples of Response Status Codes Next, the matching rules between nozzle operation types and multiplexers will be explained. Operation type refers to a sub-category of nozzle operation commands, specifically divided into control operations and monitoring operations; see [link to relevant documentation] for details. Figure 2 The target multiplexer includes at least a control multiplexer 22 and a monitoring multiplexer 23, wherein the control multiplexer adapts to all control operations and the monitoring multiplexer adapts to all monitoring operations.
[0038] It should be noted that both control and monitoring multiplexers are single-input, multi-output multi-channel signal gating circuits, and their hardware connections and control logic are as follows: (1) The input terminals of the multiplexer are all connected to the same set of control pins of the microcontroller (e.g., a total of 4 GPIO pins), and the multiple output terminals are all connected to all the nozzles in the nozzle array in a one-to-one correspondence (i.e., one output terminal of each multiplexer corresponds to one nozzle).
[0039] (2) The microcontroller outputs a binary gating code corresponding to the target nozzle through the shared GPIO control pin, and precisely controls the multiplexer's multiple outputs to only conduct one output corresponding to the target nozzle, thereby realizing the communication link with the target nozzle.
[0040] (3) The multiplexer corresponds to two mutually exclusive GPIO strobe pins to achieve unique activation and ensure that only one type of multiplexer works at the same time.
[0041] Regarding the rules for determining the multiplexer, the target multiplexer is determined based on the nozzle operation type. Specifically, if the nozzle operation type is a control operation, the control multiplexer is determined as the target multiplexer; for example, refer to... Figure 3Control operations include at least setting the correction voltage, and may also include setting waveforms, etc. Reading the correction voltage as a pre-calibration operation for setting the correction voltage also falls under the control operation category. If the nozzle operation type is a monitoring operation, the monitoring multiplexer is identified as the target multiplexer. For an example, see [link to example]. Figure 3 Monitoring operations include at least reading temperature, as well as reading status data, including but not limited to pure feedback status data such as nozzle working status, hardware fault status, and link connectivity status.
[0042] In practice, the unique activation of the multiplexer's gating is achieved through two mutually exclusive GPIO gating pins, as follows: (1) If it is a control operation, the microcontroller selects the control multiplexer through the first of the two mutually exclusive GPIO strobe pins; (2) If it is a monitoring operation, the microcontroller selects the monitoring multiplexer through the second of the two mutually exclusive GPIO selection pins; (3) After the gating operation is completed, the microcontroller delays for a preset time (e.g., 10 microseconds) before executing the subsequent link conduction action to avoid gating failure caused by signal jitter and ensure the stability of hardware operation; (4) After the two types of multiplexers are selected, they respectively enable the transmission of control and monitoring signals between the MCU and the nozzle, so as to realize the accurate execution of functional instructions.
[0043] The fault diagnosis process for status data reading is illustrated by example. For status data reading in monitoring operations, the control method also includes a fault diagnosis step. After the microcontroller unit collects the hardware fault status data of the target nozzle, it executes the following steps in sequence: (1) Compare the hardware fault status data with the preset threshold range; (2) If the hardware fault status data exceeds the preset threshold range, it is determined that the target nozzle has malfunctioned, and the target nozzle number is mapped to physical location information; (3) Generate and output a fault alarm signal carrying physical location information. The alarm signal is encapsulated in a format containing the original command code, response status code, timestamp and physical location information and fed back to the host computer, which will then provide an alarm prompt.
[0044] As can be seen from the above, the hardware structure of the multiplexer has the following advantages: 1) Multi-nozzle control can be achieved with only one set of shared control pins and two mutually exclusive gating pins, further solving the problem of limited IO resources in traditional solutions; 2) The mutually exclusive gating pins enable unique hardware-level activation for both types of multiplexers, effectively avoiding crosstalk and logic confusion between control signals and monitoring signals; 3) Binary gating encoding enables precise conduction of the target nozzle communication link, avoiding bandwidth waste and redundant signal interference; 4) Both types of multiplexers use unified address-driven logic, so when expanding the number of nozzles, only the output channels of the multiplexer need to be expanded, without the need to add new MCU control pins, reducing expansion costs and complexity. 4) Monitoring operations can cover pure feedback parameters such as nozzle temperature reading, nozzle voltage reading, operating status, hardware fault status, and link connectivity, solving the problems of difficult fault diagnosis and lack of independent status monitoring for each nozzle in existing technologies; 5) The two types of multiplexers perform their respective functions, adapting to active control operations and pure status monitoring operations respectively. This avoids mutual interference between monitoring and control signals at the hardware level, ensuring both the real-time and accurate acquisition of monitoring parameters and the stability and precision of control operation execution. See also Figure 2 It is known that the headboard also integrates an FPGA21. The FPGA is used to receive parameters sent by the MCU and send specific control commands to the nozzle. The Flash storage medium is used to store data such as voltage correction table and preset parameters, providing data support for MCU operation.
[0045] In an exemplary embodiment, when the FPGA register operation instruction is to set the firing direction, parsing the printed data packet further includes: extracting the board type flag bit and the firing direction parameter from the data payload; The control method also includes: determining the register address corresponding to the FPGA based on the board type flag bit, writing the ignition direction parameter into the target register corresponding to the register address; the FPGA reads the ignition direction parameter in the target register and generates the corresponding ignition control signal, and sends the ignition control signal to the corresponding nozzle to complete the setting of the ignition direction.
[0046] As can be seen from the above, by automatically matching the corresponding FPGA register address through the board type flag, it is possible to adapt to the nozzle control of different types of boards, realize the precise configuration and distribution of ignition direction parameters, and ensure the accuracy of nozzle ignition control and hardware compatibility.
[0047] In an exemplary embodiment, when the printhead operation instruction is to set the printhead DO output operation, parsing the print data packet further includes: extracting the enable bit, the first status bit, and the GPIO port number from the data payload of the print data packet; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation commands, including: The target multiplexer is controlled to conduct the communication link according to the target nozzle information. If the enable bit is in an active state, the target GPIO port corresponding to the target nozzle is located according to the GPIO port number, and the target GPIO port is set to high or low level according to the instruction of the first state bit. If the enable bit is invalid, the target GPIO port will maintain its original level and no output adjustment operation will be performed. The GPIO port number is a fixed general-purpose input / output port number pre-configured for the target nozzle, used to specify the specific GPIO port for which the DO output operation needs to be performed.
[0048] Specifically, DO output operation, or digital output operation, is a type of operation in the printing system of this invention that controls the hardware switch by controlling the level state of the GPIO port. Depending on the controlled object, it can be divided into two categories: setting printhead DO output operation and other hardware DO output operation. The difference between the two lies in whether or not a multiplexer is involved in the selection and use of the multiplexer.
[0049] Setting up printhead DO output operations controls the printhead's auxiliary hardware and is a printhead-specific control operation. It requires a multiplexer to establish the communication link with the target printhead and is a supportive operation ensuring normal printhead operation. Other hardware DO output operations control independent hardware within the printing system other than the printhead and do not rely on the printhead's communication link. Therefore, they do not involve the selection or use of a multiplexer. Examples include controlling the start / stop of the paper feed motor on the printing platform, the on / off switch of the cooling fan on the equipment casing, and the power supply to the consumable level detection module.
[0050] The purpose of setting the nozzle DO output is to provide supporting protection for the nozzle operation. This is different from operations such as voltage configuration and temperature reading, which directly affect the core functions of the nozzle. Specific application scenarios include: starting and stopping the nozzle cleaning module, switching the nozzle heating and insulation module on and off, triggering the nozzle anti-clogging spray device, and controlling the opening and closing of the nozzle dust cover.
[0051] To ensure precise and controllable operation, the following example illustrates the parameter definitions for setting the nozzle DO output operation: Enable bit: 1-byte digital instruction, which is the core parameter for operation start / stop control. It only contains two states: valid and invalid, with no intermediate states. When valid, it triggers a level adjustment operation. When invalid, it maintains the original state of the target GPIO port, which can avoid hardware abnormalities caused by invalid level adjustment. First status bit: 1 byte digital instruction, which is a level control parameter. It contains only two types of instructions: high level and low level, and is used to specify the output status of the target GPIO port. GPIO port number: A 1-byte numeric identifier, which can be a fixed port number pre-configured for the target printhead. It is uniquely bound to the printhead and used to accurately locate the specific GPIO port that needs to perform the DO output operation.
[0052] As can be seen from the above, the start / stop control of the enable bit can accurately trigger the setting of the nozzle DO output operation; combined with the pre-configuration of the GPIO port and the explicit instructions of the status bit, it not only avoids invalid operations, but also supports custom port configuration and automatic adaptation of the default port, taking into account the flexibility, ease of use and stability of GPIO control.
[0053] In an exemplary embodiment, when the command type is a file system operation instruction, parsing the print data packet further includes: extracting a file operation sub-command, a second status bit, and corresponding sub-parameters from the data payload; wherein, the file operation sub-command is a detailed instruction of the file system operation, used to identify the specific type of file operation, and the file operation sub-command includes at least a download file sub-command and a read file sub-command; the sub-parameters are auxiliary parameters required to perform the file system operation, and the sub-parameters include file type, board type, printhead type, file save location, and a 4-byte checksum.
[0054] The control method also includes: performing file download operations based on the file download sub-command, the second status bit, and the corresponding sub-parameters.
[0055] The file download operation is performed based on the download file subcommand, the second status bit, and the corresponding sub-parameters. Specifically, it may include: If the second status bit is the start status (e.g., the start status is 0x01), extract the file type and detailed parameters from the sub-parameters; If the file type is a waveform file, then parse the nozzle type and file save location in the sub-parameters, and determine the Flash storage area based on the nozzle type and file save location; If the file type is voltage correction file, then locate the storage address of the voltage correction table according to the board type in the sub-parameter; Erase the existing data in the target storage area identified above, and set a new programming address for subsequent file data writing; If the second status bit is a data transmission status (e.g., data transmission status is 0x02), the print data packet sent by the host computer is divided into an instruction data packet and a block file data packet. The file data block sent by the host computer received here is the data payload part of the block file data packet. It belongs to the file download operation associated data packet with the instruction data packet received in step S1 and is used to transmit the main file data. The MCU receives the file data block, calculates the checksum of each data block in real time, and writes the file data block to the specified address in the preset Flash storage area. Update the current write address pointer and accumulate the amount of data received to determine whether the file transfer is complete; If the second status bit is the end of transmission status (e.g., the end of transmission status is 0x03), extract 4 bytes of checksum from the sub-parameters. This checksum is the total file checksum pre-calculated by the host computer and is compared with the total file checksum accumulated by the MCU during the data transmission process. If the verification passes, the MCU sets the file data storage address to valid, updates the file system index, and generates an execution result indicating that the file download was successful. If the verification fails, the MCU generates an execution result indicating a file download error, erases the invalid data already written to the Flash storage area, and keeps the original files in that area unchanged, ensuring the integrity of the file system data.
[0056] The above content integrates file system operations into the printing system's command tree. 1) Through phased control from "start to end" and full-process verification and comparison, it solves the problems of packet loss and data corruption during the transmission of large configuration files (waveform, voltage correction files), ensuring complete file delivery; 2) The file storage address is bound to the printhead type and board type to avoid configuration file confusion in multi-printhead / multi-headboard scenarios, providing a reliable data foundation for subsequent precise control of printhead voltage and ignition direction; 3) When transmission verification fails, invalid data is automatically erased and the original file is retained, eliminating the need for manual repair and adapting to the continuous working requirements of industrial scenarios; 4) It shares a standardized parsing framework with printhead control operations, and adding new file types / hardware models only requires expanding sub-parameters, without refactoring the process, reducing system upgrade costs.
[0057] In an exemplary embodiment, parsing the print data packet further includes: extracting target nozzle information from the data payload; the target nozzle information is either a single-point nozzle number or full-volume nozzle control parameters.
[0058] Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation commands, including: If the target nozzle information is a single-point nozzle number, the target multiplexer is controlled in fixed-point mode to connect the communication link corresponding to the single-point nozzle number, and the nozzle operation command is sent to the target nozzle so that the target nozzle performs the corresponding action. If the target nozzle information is the full range of nozzle control parameters, the target multiplexer is controlled in polling mode to sequentially activate the communication links corresponding to each nozzle according to a preset timing sequence, and the nozzle operation commands are sent to each nozzle one by one, so that each nozzle executes the corresponding action in sequence.
[0059] Specifically, the single-point nozzle number is a unique identifier for a single nozzle (usually a numeric code from 0 to 15). This single-point nozzle number is the nozzle identifier for a single nozzle and is a single-value representation of the nozzle identifier. The single-point nozzle number contains only 1 byte of nozzle number in the data payload (e.g., 0x05 corresponds to nozzle number 5), and the data length is short (e.g., len=0x0001).
[0060] Single-point nozzle number triggers fixed-point mode, which only performs operations on the specified nozzle and does not affect the operation of other nozzles.
[0061] For example, when the host computer issues a nozzle operation command to "read the temperature of nozzle #8", the data payload contains the single-point nozzle number "0x08", and the data packet format can be [cmd=temperature reading code+len=0x0001+ret=0x01+data=0x08]. At this time, the MCU extracts the single-point nozzle number "0x08", triggers the fixed-point mode, and only connects the communication link of nozzle #8 to perform temperature reading.
[0062] The full-volume printhead control parameters are a set of batch operation parameters covering all printheads, including the execution parameters of each printhead (such as voltage values, waveform parameters, etc.) and corresponding to the batch operation range of all printheads. The full-volume printhead control parameters themselves do not directly carry discrete printhead identifiers, but the order of the parameter set corresponds one-to-one with the identifiers of printheads 1-16 (the first group of parameters corresponds to printhead identifier 1, the second group to printhead identifier 2, and so on, up to printhead identifier 16). The full-volume printhead control parameters include the operation parameters of all printheads (e.g., voltage values for 16 printheads) in the data payload, and the data length is long (e.g., len=0x0020, corresponding to 16 groups of parameters).
[0063] The full range of nozzle control parameters triggers a polling mode, performing operations on each nozzle sequentially according to a preset time sequence to achieve batch unified configuration.
[0064] For example, when the host computer issues a nozzle operation command to "set the operating voltage of all 16 nozzles to 3.3V", the data payload contains 16 sets of voltage parameters (each set of parameters corresponds to the 3.3V configuration of one nozzle), and the data packet format is as follows: [cmd=voltage setting code+len=0x0020+ret=0x01+data=3.3V|3.3V|...|3.3V (16 groups)]. At this time, the MCU extracts all the nozzle control parameters, triggers the polling mode, and configures the 3.3V voltage for nozzles 1-16 in sequence.
[0065] A multiplexer is a hardware device that selects and enables multiple signals, allowing switching control of multiple printhead channels through a small number of control pins. For example, a printing system with 16 printheads can be configured with 4 control pins. The microcontroller unit connects to the input of the multiplexer through these 4 control pins. The multiplexer has 16 output pins, each corresponding to printheads 1 through 16. The microcontroller unit also connects to the enable pin of the multiplexer through an enable pin, enabling precise control of the multiplexer's on / off state.
[0066] The four control pins can output a four-bit binary strobe signal, which can accurately match the channel selection of the 16 nozzles from 1 to 16 through 16 binary codes from 0000 to 1111. For example, the specific coding mapping relationship is as follows: binary signal 0000 corresponds to selecting nozzle 1, 0001 corresponds to selecting nozzle 2, 0010 corresponds to selecting nozzle 3, 0011 corresponds to selecting nozzle 4, 0100 corresponds to selecting nozzle 5, 0101 corresponds to selecting nozzle 6, 0110 corresponds to selecting nozzle 7, 0111 corresponds to selecting nozzle 8; and so on, 1000 corresponds to selecting nozzle 9, 1001 corresponds to selecting nozzle 10, 1010 corresponds to selecting nozzle 11, 1011 corresponds to selecting nozzle 12, 1100 corresponds to selecting nozzle 13, 1101 corresponds to selecting nozzle 14, 1110 corresponds to selecting nozzle 15, and so on, until 1111 corresponds to selecting nozzle 16.
[0067] Through the above encoding mapping, the microcontroller only needs to output a set of 4-bit signals to accurately connect the communication link of the target nozzle within a very short time (e.g., 5 microseconds), realizing the efficient multiplexing of 16 nozzle channels by a single set of control pins, which greatly reduces the occupation of hardware pin resources and system costs.
[0068] When the target multiplexer controls the target nozzle to execute the action corresponding to the nozzle operation command, the communication link connection process is as follows: In the process of controlling the target multiplexer to connect the corresponding communication link based on the target nozzle information, the microcontroller converts the nozzle identifier into a 4-bit binary code gating control signal through binary bit operation, and outputs the gating control signal to the selected target multiplexer through 4 control pins, controlling it to complete the channel connection with the target nozzle within a set time (e.g., 5 microseconds).
[0069] For example, when performing batch operations in polling mode, the microcontroller maintains the selected active state of the target multiplexer and obtains a parameter array containing the execution parameters of all nozzles; the microcontroller generates gating control signals sequentially from the 1st to the 16th nozzle, and outputs them cyclically through 4 control pins. After each switch, the target multiplexer is controlled to conduct the corresponding nozzle channel for a preset time (e.g., 5 microseconds); for each nozzle, after the channel is conducted, the corresponding control or monitoring operation is executed. After the operation is completed, a delay of a certain time (e.g., 50 microseconds) is performed to wait for the nozzle response, and then the system immediately switches to the next nozzle channel.
[0070] In this embodiment, the execution modes of printhead operation are divided into fixed-point mode and polling mode. The core reasons are as follows: 1) In industrial printing scenarios, there is a need for precise positioning of a single printhead for fault diagnosis and individual calibration (e.g., when the temperature of a certain printhead is abnormal, only the temperature of that printhead is read), and there is also a need for unified configuration and batch monitoring of all printheads (e.g., setting a unified working voltage for all printheads before printing). The two modes are adapted to these two core scenarios respectively. Single-point operation does not need to occupy all printhead channel resources, while batch operation needs to efficiently complete the configuration of all printheads. Separate design can avoid resource waste or inefficiency. 2) If only the polling mode is used to handle single-point operation, the MCU will traverse all printheads in turn. Even if only one printhead needs to be operated, it is necessary to wait for the other printhead channels to switch to complete, which greatly reduces the response speed. If only the fixed-point mode is used to handle batch operation, the host computer needs to issue single-point commands multiple times, which increases the amount of data transmission and communication latency, and it is impossible to achieve unified synchronous configuration of all printheads. 3) Monitoring operations often require quick location of a single abnormal nozzle, which can be accomplished accurately and efficiently in the fixed-point mode; control operations often require unified configuration of all nozzles, which can be accomplished in an orderly manner in the polling mode, avoiding signal conflicts caused by simultaneous operation of multiple nozzles.
[0071] In an exemplary embodiment, when the printhead operation command is a read correction voltage command, parsing the print data packet further includes: extracting board head parameters, voltage data type, and printhead parameters from the data payload; wherein the voltage data type includes a voltage unit identifier 0x01 and a percentage unit identifier 0x02, the voltage unit identifier 0x01 corresponds to a unit of 0.01V, and the percentage unit identifier 0x02 corresponds to a unit of 0.01%, and the printhead parameters include the number of printheads and the specific parameters of each printhead, including printhead ID, temperature information, calibration status, etc.
[0072] Based on the target nozzle information, the target multiplexer controls the target nozzle to execute actions corresponding to the nozzle operation commands, which may include: Verify the validity of the board header parameters and check their consistency with the system configuration; Extract the number of nozzles, and then analyze the parameter information of each nozzle one by one based on the number; If the target nozzle information is a single-point nozzle number, the monitoring multiplexer is controlled in fixed-point mode to connect the corresponding nozzle communication link; if the target nozzle information is full-number nozzle control parameters, the monitoring multiplexer is controlled in polling mode to connect the communication links of each nozzle in a preset sequence; address positioning, raw voltage data reading and data conversion compensation operations are performed for each nozzle, and channel switching is achieved through a multiplexer; Pack all the voltage data of the nozzles in order, add header information such as the number of nozzles and voltage type, and calculate the data packet verification information; The packaged voltage data is fed back to the host computer according to the response flag requirements, including complete metadata information and error status reports.
[0073] In an exemplary embodiment, when the command type is other system function instructions, parsing the print data packet further includes: extracting the system operation subtype and corresponding auxiliary parameters from the data payload. The system operation subtype is 1 byte, and the auxiliary parameters are variable length. The system operation subtype includes system-level operations such as system reset and log export.
[0074] The control method may also include: executing corresponding system-level actions based on the system operation subtype. Specifically, executing corresponding system-level actions based on the system operation subtype may include: If it is a system reset subtype, the MCU triggers the system soft reset process, resets all register states, multiplexer channel states and nozzle configuration parameters, and sends a reset success response to the host computer after the reset is completed. If it is a log export subtype: the MCU reads the system operation log from the storage medium. The system operation log includes fault records, operation records, etc., and is packaged according to the protocol format and sent to the host computer. After the export is completed, the log size and integrity verification results are returned. Other system-level operations: Execute according to the preset process of the corresponding subtype, and after the execution is completed, return the operation result according to the response flag requirements to ensure that the host computer knows the system status in real time.
[0075] For example, when the nozzle operation command is to set the correction voltage and the target nozzle information is the full range of nozzle control parameters, based on the target nozzle information, the target multiplexer controls the target nozzle to execute the action corresponding to the nozzle operation command, including: The control multiplexer is controlled in polling mode to sequentially activate the communication link corresponding to each nozzle according to a preset timing sequence and read the operating voltage of each nozzle. The actual correction voltage of each nozzle is calculated by comparing its operating voltage with the corresponding reference correction voltage in the voltage correction table; the voltage correction table is a pre-stored correction table retrieved from the Flash storage medium. The control multiplexer is controlled in polling mode to sequentially activate the communication link corresponding to each nozzle according to a preset timing sequence and set the actual correction voltage of each nozzle; after each nozzle receives and loads the actual correction voltage, the control multiplexer is controlled to disconnect the communication link.
[0076] For example, taking a 16-printer industrial printing system as an example, the specific control process is as follows: (1) The host computer sends a nozzle operation command to “batch set the correction voltage of all nozzles” (belonging to the control operation). The data packet format is: [cmd=correction voltage setting code+len=0x0020+ret=0x01+data=voltage data type (0x01, unit 0.01V)+correction threshold parameter (±0.1V)]. The data payload contains all nozzle control parameters (implying the calibration requirements of 16 nozzles). (2) The MCU parses the command code and determines that it is a control operation. It automatically calls the function SelectMuxType(MUX_TYPE_COMM) to activate the control multiplexer, disconnects the monitoring multiplexer, and performs a 10μs delay to ensure the stability of the multiplexer; (3) Perform operations in polling mode: Step 1: The MCU calls the function HAL_GpioMuxSwitchSet(0) to select the channel of nozzle 0 (e.g., binary code 0000), connects the communication link of nozzle 0, and reads the current operating voltage of nozzle 0 (e.g., 3.25V). Step 2: Retrieve the voltage correction table from the Flash storage medium, look up the reference correction voltage (e.g., 3.30V) corresponding to printhead 0, and calculate the actual correction voltage (3.30V + (3.30V - 3.25V) = 3.35V) by combining the correction threshold parameter (±0.1V). This is used to compensate for the deviation between the current voltage and the reference voltage. Step 3: Keep the control multiplexer active and send a 3.35V actual correction voltage to nozzle 0 through the same channel, and wait for the nozzle to finish loading; Step 4: Call the function HAL_GpioMuxSwitchSet(1) to switch to nozzle channel 1 (binary code 0001), repeat the above "read-calculate-set" process, and complete the correction voltage configuration of nozzles 0-15 in sequence; After all nozzles are loaded, the MCU calls the SelectMuxType function to disconnect the communication multiplexer, release the channel resources, and return a response data packet containing the configuration results of 16 nozzles to the host computer according to the response flag (e.g., ret=0x01).
[0077] The printing system provided by the present invention is described below. The control method of the printing system described below can be referred to in correspondence with the printing system described above.
[0078] like Figure 2 As shown, embodiments of the present invention also provide a printing system for implementing the control method of the printing system in any of the above embodiments. The printing system may include: The host computer 1, the headboard 2, and the nozzle array 3 are included. The headboard integrates at least a microcontroller 20 and a multiplexer. The host computer 1 is communicatively connected to the microcontroller 20, and the microcontroller 20 is electrically connected to the multiplexer. The microcontroller unit is used to receive print data packets sent by the host computer and parse the print data packets to obtain the parsing results; the parsing results include at least the printhead operation instructions, printhead operation type and target printhead information; Determine the target multiplexer based on the nozzle operation type; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation instructions.
[0079] Furthermore, the printing system also includes a Flash storage medium; the headboard 2 also integrates an FPGA 21; the multiplexer includes a control multiplexer 22 and a monitoring multiplexer 23; the control multiplexer and the monitoring multiplexer are respectively connected to all printheads in the printhead array through communication links; the FPGA 21 is electrically connected to the microcontroller unit 20, and the FPGA 21 is used to receive parameters issued by the microcontroller unit and send specific control commands to the corresponding printheads; Control multiplexer 22 and monitoring multiplexer 23 share the same set of control pins of the microcontroller unit and are connected to the microcontroller unit through two mutually exclusive GPIO strobe pins, enabling unique activation of a single multiplexer; the Flash storage medium is electrically connected to the microcontroller unit. The Flash storage medium is used to store voltage correction tables, file data, checksums, and preset parameters, providing hardware support for the MCU's parsing, calibration, and storage operations.
[0080] In summary, the printing system control method and printing system of the present invention have the following beneficial effects: 1) The binary-coded multiplexer control architecture simplifies the 4n IO pins required to control n nozzles in the traditional scheme into 4 general-purpose control pins and 2 mutually exclusive gating pins, realizing efficient pin multiplexing in multi-nozzle systems, simplifying hardware design and layout, reducing system hardware costs, and improving overall system stability.
[0081] 2) Based on dynamic channel switching and pseudo-concurrency processing mechanism, through flexible switching of fixed point / polling mode and fast selection of multiplexer, efficient scheduling and collaborative work of multiple nozzles are achieved. Compared with the traditional pure sequential processing scheme, the efficiency of multi-nozzle collaborative work is improved, and it supports the expansion requirements of up to 16 nozzles without modifying the MCU hardware pins and underlying drivers, thus significantly improving the system scalability.
[0082] 3) Based on a modular and configurable software architecture design, functions such as command parsing, multiplexer control, file operation, and FPGA register operation are modularly decomposed, abandoning the traditional hard-coded design method. It supports the adaptation of different nozzle models and board types through configuration parameters, which shortens the development cycle for adapting to different nozzle models and reduces the maintenance cost of the system in the later stage.
[0083] 4) By combining intelligent status monitoring and full-process data verification, independent real-time monitoring of printhead temperature, voltage, and fault status is achieved, solving the problem of difficult fault diagnosis in traditional solutions. At the same time, through phased verification of file transmission and error feedback of command execution, the reliability of system operation is further guaranteed. Ultimately, the system achieves the overall technical effect of efficient utilization of hardware resources, faster system response speed, improved scalability and adaptability, and reduced overall hardware and maintenance costs, which can perfectly adapt to the application requirements of industrial-grade high-speed multi-printhead printing.
[0084] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, the disclosure, and the appended claims in carrying out the claimed invention. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. Although the invention has been described in conjunction with specific features and embodiments, it is apparent that various modifications and combinations can be made thereto without departing from the spirit and scope of the invention. Accordingly, this specification and the accompanying drawings are merely exemplary descriptions of the invention as defined by the appended claims and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the invention. Obviously, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if such modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include such modifications and modifications.
Claims
1. A control method for a printing system, characterized in that, include: The microcontroller receives the print data packet sent by the host computer and parses the print data packet to obtain the parsing result; The analysis results include at least the nozzle operation command, the nozzle operation type, and the target nozzle information; The target multiplexer is determined based on the nozzle operation type; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation command.
2. The control method for the printing system according to claim 1, characterized in that, The printed data packet contains at least a command code; Parsing the printed data packet includes: Extract the command code from the printed data packet, and identify the command code to obtain the command type; The command type includes one of the following: nozzle operation instructions, FPGA register operation instructions, and file system operation instructions.
3. The control method for the printing system according to claim 2, characterized in that, Based on the nozzle operation type, the target multiplexer is determined, including: If the nozzle operation type is a control operation, the control multiplexer is identified as the target multiplexer; the control operation includes at least setting a correction voltage; If the nozzle operation type is a monitoring operation, the monitoring multiplexer is identified as the target multiplexer; the monitoring operation includes at least reading temperature; the control multiplexer and the monitoring multiplexer share the same set of control pins of the microcontroller unit.
4. The control method for the printing system according to claim 3, characterized in that, The printed data packet also contains a data payload; Parsing the printed data packet further includes: extracting the target nozzle information from the data payload; the target nozzle information is a single-point nozzle number or full-volume nozzle control parameters; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation command, including: If the target nozzle information is the single-point nozzle number, then the target multiplexer is controlled in fixed-point mode to connect the communication link corresponding to the single-point nozzle number, and the nozzle operation command is sent to the target nozzle so that the target nozzle performs the corresponding action. If the target nozzle information is the full range of nozzle control parameters, then the target multiplexer is controlled in polling mode to sequentially connect the communication links corresponding to each nozzle according to a preset timing sequence, and the nozzle operation command is sent to each nozzle one by one, so that each nozzle executes the corresponding action in sequence.
5. The control method for the printing system according to claim 4, characterized in that, When the nozzle operation command is to set the correction voltage and the target nozzle information is the full-volume nozzle control parameters, based on the target nozzle information, the target multiplexer controls the target nozzle to execute the action corresponding to the nozzle operation command, including: The polling mode controls the control multiplexer to sequentially activate the communication link corresponding to each nozzle according to the preset timing sequence and read the operating voltage of each nozzle. The actual correction voltage of each nozzle is calculated by comparing its operating voltage with the corresponding reference correction voltage in the voltage correction table; the voltage correction table is a pre-stored correction table retrieved from the Flash storage medium. The polling mode controls the control multiplexer to sequentially activate the communication links corresponding to each nozzle according to the preset timing and set the actual correction voltage of each nozzle.
6. The control method for the printing system according to claim 4, characterized in that, When the printhead operation instruction is to set the printhead DO output operation, parsing the print data packet also includes: extracting the enable bit, the first status bit and the GPIO port number from the data payload; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation command, including: The target multiplexer is controlled to activate the communication link according to the target nozzle information. If the enable bit is in an active state, the target GPIO port corresponding to the target nozzle is located according to the GPIO port number, and the target GPIO port is set to a high level or a low level according to the instruction of the first state bit. If the enable bit is invalid, the original level of the target GPIO port is maintained, and no output adjustment operation is performed.
7. The control method for the printing system according to claim 2, characterized in that, The printed data packet also includes a response flag; the response flag is used to indicate whether it is necessary to send the result back to the host computer. The control method further includes: after controlling the target nozzle to perform the action corresponding to the nozzle operation command through the target multiplexer based on the target nozzle information, feeding back the operation execution result to the host computer based on the response flag; The operation execution result is fed back to the host computer based on the response flag, including: If the response flag indicates that feedback is required, a response data packet is generated and sent to the host computer; wherein, the response data packet includes at least the original command code, the response status code, and the timestamp; the original command code is the command code in the printed data packet, the response status code is used to identify the operation execution result, and the timestamp records the operation completion time; the operation execution result includes operation success, parameter error, verification failure, board mismatch, and unknown error; If the response flag indicates that no feedback is required, neither the response data packet nor the response data packet will be generated or sent.
8. The control method for the printing system according to claim 4, characterized in that, When the FPGA register operation instruction is to set the firing direction, parsing the printed data packet also includes: extracting the board type flag and firing direction parameters from the data payload; The control method further includes: The FPGA register address is determined based on the board type flag, and the ignition direction parameter is written into the target register corresponding to the register address. The FPGA reads the ignition direction parameter in the target register and generates the corresponding ignition control signal, and sends the ignition control signal to the corresponding nozzle to complete the setting of the ignition direction.
9. A printing system, characterized in that, include: The host computer, the headboard, and the nozzle array; the headboard integrates at least a microcontroller and a multiplexer. The host computer is communicatively connected to the microcontroller unit, and the microcontroller unit is electrically connected to the multiplexer; The microcontroller unit is used to receive print data packets sent by the host computer and parse the print data packets to obtain parsing results; the parsing results include at least printhead operation instructions, printhead operation type and target printhead information; The target multiplexer is determined based on the nozzle operation type; Based on the target nozzle information, the target multiplexer controls the target nozzle to execute the actions corresponding to the nozzle operation command.
10. The printing system according to claim 9, characterized in that, Also includes: Flash storage medium; the Flash storage medium is electrically connected to the microcontroller unit; The headboard also integrates an FPGA; the FPGA is electrically connected to the microcontroller unit. The multiplexer includes a control multiplexer and a monitoring multiplexer; the control multiplexer and the monitoring multiplexer are respectively connected to all nozzles in the nozzle array via communication links; the control multiplexer and the monitoring multiplexer share the same set of control pins of the microcontroller unit.