Control method and system of display device

Abstract

The invention relates to the technical field of display, in particular to a control method and system of a display device, and the display device configures entity COM ports in a one-to-one correspondence manner according to the number of display devices, and configures at least one virtual COM port according to the information storage duration; the display device averagely distributes time to each entity COM port and each virtual COM port according to the total scanning duration of a single cycle to obtain a scanning interval duration Anum; the display device scans and drives all the entity COM ports and all the virtual COM ports in turn according to the scanning interval duration Anum, and the scanning driving sequence is that all the entity COM ports are sequentially driven firstly, and then all the virtual COM ports are sequentially driven; the display device synchronously carries out power failure detection, and when power failure is confirmed and a first virtual COM port is scanned and driven, the display device carries out information storage; the problem of display flicker caused by intervention of an information storage event during power failure is solved.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a control method and system for a display device. Background Technology

[0002] In display devices, taking digital tubes as an example, using a common anode connection, the display control is achieved through the I / O ports of a microcontroller (such as an MCU) to perform chip select scanning on n digital tubes (i.e., scanning the COM ports of each digital tube in turn). One COM port is turned on in turn for each time period, and then the LED segment of that digital tube is turned on as needed. Taking four digital tubes as an example, assuming a refresh rate of 125Hz (based on the human eye's perception threshold for flicker during dynamic scanning, it is usually set above 75Hz, i.e., flicker is imperceptible), for four COM ports, it takes 2ms to go from one COM port to the next, and the total time for one complete scan is 8ms.

[0003] However, the internal EEPROM based on the microprocessor requires at least 3ms to write. For display devices with power-off memory function, the execution time for saving information triggered by power failure is at least 3ms, which exceeds the 2ms scanning time between the two COM ports. This will disrupt the normal scanning and display work, resulting in a flickering display during the information saving process, which makes the user experience poor. Summary of the Invention

[0004] To address the aforementioned shortcomings, the present invention aims to provide a control method and system for a display device, which solves the display flickering problem caused by the intervention of information saving events during power failure.

[0005] To achieve this objective, the present invention adopts the following technical solution: A control method for a display device, wherein the display device configures physical COM ports one-to-one according to the number of display devices, and configures at least one virtual COM port according to the information storage duration; the display device distributes the time equally to each physical COM port and each virtual COM port according to the total scan duration of a single cycle, to obtain a scan interval duration Anum; The display device scans and drives all the physical COM ports and all the virtual COM ports in turn according to the scanning interval duration Anum, and the scanning and driving order is: first drive all the physical COM ports in sequence, and then drive all the virtual COM ports in sequence. The display device performs power failure detection synchronously. When a power failure is confirmed and the device scans and drives to the first virtual COM port, the display device saves the information.

[0006] Furthermore, when the display device scans and drives the physical COM port, it drives the corresponding display device to work; When the display device scans and drives to the virtual COM port, a no-operation occurs.

[0007] Furthermore, the execution program of the display device includes the following steps: A1: Convert the scan interval duration Annum into a scan count value An, and count it using a scan counter. When the scan counter counts to the scan count value An, execute step A3. A2: Perform power failure detection. The power failure flag is set to 1 only when a power failure is confirmed; otherwise, the power failure flag is set to 0. A3: A drive counter is configured. Based on the current count value of the drive counter, the corresponding physical COM port or the virtual COM port is selected for driving. After the driving is completed, the drive counter is incremented by 1, and the process returns to step A1. When the first virtual COM port is driven, step A4 is executed synchronously; A4: Determine the power failure flag (Flag); when the power failure flag (Flag) is 1, save the information.

[0008] Furthermore, step A3 also includes: configuring the total number of the physical COM ports and the virtual COM ports as a sequence count value Bnum; After the drive counter increments by 1, determine whether the current count value of the drive counter is equal to the sequence count value Bnum; if yes, clear the drive counter and return to step A1; otherwise, return to step A1.

[0009] Furthermore, in step A1: the scan count value An is: An=[1000000 / F / (sCOM+xCOM) / T]; Where F is the refresh frequency selected according to the scan interval duration Anum, sCOM is the number of physical COM ports, xCOM is the number of virtual COM ports, and T is the timer interrupt response time built into the display device; The calculated value of the scan count An needs to be rounded to the nearest integer.

[0010] Furthermore, step A4 includes the following sub-steps: A41: Determine the power-down flag (Flag); when the power-down flag (Flag) is 1, execute sub-step A42; A42: Compare the information to be saved with the information stored in the power-down memory; if the information is the same, end this step; if the information is different, update the information stored in the power-down memory to the information to be saved, and then set the count value of the drive counter to Bnum-1.

[0011] Furthermore, sub-step A41 also includes: when the power-down flag is 1, setting the power-down flag to 0.

[0012] Furthermore, in step A2: power failure detection includes: detecting whether the power supply voltage VDD is lower than a preset low voltage threshold; if so, then confirming power failure.

[0013] Furthermore, before performing step A3, all entity COM ports are closed.

[0014] A control system for a display device, characterized in that: executing the above-described control method for a display device includes: Scan interval module: Configures a scan counter to ensure the scan interval duration Anum; Power failure detection module: used for power failure detection; Port module: used to configure the physical COM port and the virtual COM port in sequence; and to receive port output data, which corresponds one-to-one with the physical COM port; Port driver module: Configures a driver counter to cyclically obtain the scan interval duration Anum from the scan interval module, and scans the physical COM port and the virtual COM port that drive the port module in turn; Information storage module: When the port driver module scans and drives the first virtual COM port, it interacts with the power failure detection module to determine whether information needs to be stored; and configures a power failure memory for information storage.

[0015] The technical solution provided by this invention can include the following beneficial effects: By adding virtual COM ports to match the information storage duration, taking four physical COM ports and one virtual COM port as an example, the total scan duration of a single cycle is evenly distributed, then the scan interval duration Anum = 1.142ms, and the total duration of the virtual COM ports is 3.426ms, which is approximately the information storage duration (i.e., equivalent to the refresh time of 3~3.5ms required by EEPROM). Thus, the information storage event intervenes when the first virtual COM port is scanned, thereby solving the display flickering problem caused by the intervention of the information storage event when power is off. Attached Figure Description

[0016] Figure 1This is a schematic diagram of a display device control method according to one embodiment of the present invention.

[0017] Figure 2 Is it like this? Figure 1 The diagram shows a flowchart of a control method for a display device.

[0018] Figure 3 Is it like this? Figure 1 The flowchart for step A3 is shown below.

[0019] Figure 4 Is it like this? Figure 1 The flowchart for step A4 is shown below.

[0020] Figure 5 This is a schematic diagram of a control system for a display device according to one embodiment of the present invention.

[0021] The components include: display device 1, physical COM port 2, virtual COM port 3, scanning interval module 10, power failure detection module 20, port module 30, port driver module 40, and information storage module 50. Detailed Implementation

[0022] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0023] In the description of embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.

[0025] The following is combined Figures 1 to 5This invention describes a control method and system for a display device according to an embodiment of the present invention.

[0026] Example 1 A control method for a display device, wherein the display device configures physical COM ports 2 in a one-to-one correspondence with the number of display devices 1, and configures at least one virtual COM port 3 according to the information storage duration; the display device distributes the time equally to each physical COM port 2 and each virtual COM port 3 according to the total scan duration of a single cycle, to obtain the scan interval duration Anum; The display device scans and drives all physical COM ports 2 and all virtual COM ports 3 in turn according to the scan interval time Anum, and the scanning and driving order is: first drive all physical COM ports 2 in sequence, and then drive all virtual COM ports 3 in sequence. The display device performs power failure detection simultaneously. When a power failure is confirmed and the driver is scanned to the first virtual COM port 3, the display device saves the information.

[0027] The traditional sequential scanning of physical COM ports 2 (taking four physical COM ports 2 as an example) involves a 2ms interval between COM1 and COM2, 2ms between COM2 and COM3, 2ms between COM3 and COM4, ​​and 2ms between COM4 and COM1, resulting in a total scan time of 8ms for a single cycle. When power is lost, regardless of when the information event is initiated, the saving time requires at least 3ms (generally, the refresh time for an EEPROM is 3ms to 3.5ms), exceeding the interval of a single cycle and causing a flickering display. Therefore, this invention proposes a preferred embodiment of a control method for a display device, such as... Figure 1 As shown, by adding a virtual COM port 3 to match the information storage duration, taking four physical COM ports 2 and three virtual COM ports 3 as an example, the total scan duration of a single cycle is evenly distributed, so the scan interval duration Anum = 1.142ms. At this time, the total duration of the three virtual COM ports 3 is 3.426ms, which is approximately the information storage duration (i.e., equivalent to the refresh time required by EEPROM, which is 3~3.5ms). Thus, the information storage event intervenes when the first virtual COM port 3 is scanned, thereby solving the display flickering problem caused by the intervention of the information storage event when power is off.

[0028] Furthermore, when the display device scans and drives to the physical COM port 2, it drives the corresponding display device 1 to work; When the display device scans the driver to virtual COM port 3, no operation occurs.

[0029] In this embodiment, the virtual COM port 3 is used to match the information storage duration and has no port signal output, so the program performs a no-operation to avoid affecting the actual display effect; while the physical COM port 2 is driven by the display device (the microprocessor therein) to work as needed (such as lighting up the LED segments of the digital tube as needed) according to the display requirements.

[0030] Furthermore, the execution program of the display device includes the following steps: A1: Convert the scan interval duration Annum into a scan count value An, and count it using the scan counter. When the scan counter counts to the scan count value An, execute step A3. A2: Perform power failure detection. The power failure flag is set to 1 only when a power failure is confirmed; otherwise, the power failure flag is set to 0. A3: A drive counter is configured. Based on the current count value of the drive counter, select the corresponding physical COM port 2 or virtual COM port 3 for driving. After the driving is completed, the drive counter is incremented by 1, and the process returns to step A1. When the first virtual COM port 3 is driven, step A4 is executed synchronously; A4: Determine the power failure flag (Flag); when the power failure flag (Flag) is 1, save the information.

[0031] In this embodiment, the execution program logic of the display device (including the microcontroller) is as follows: Figure 2 As shown, step A1 converts the scan interval duration Anum into a scan count value An, and controls the timing through the scan counter to precisely control the time interval of port scanning, avoiding display flickering due to timing disorder. Step A2, on the other hand, executes the program in parallel, performing real-time power failure detection independently, without occupying the main scan timing and without affecting normal display driving.

[0032] Each execution of step A3 is equivalent to a drive event for one port. By looping with step A1 and accumulating the drive counter, the port is scanned in turn. At the moment of the first virtual COM port 3 drive, the power-down flag is triggered to determine whether to start the information saving event in step A4, so as to synchronize the total time of the subsequent virtual COM port 3 scan with the time of the information saving event.

[0033] It is important to note that the correspondence between the accumulated count value of the drive counter and the port is arranged in sequence; for example, after the end of the previous loop, the count value corresponding to the last port reaches n+m+1, then the count value corresponding to the first port in the next loop reaches n+m+2, and so on.

[0034] Furthermore, step A3 also includes: configuring the total number of physical COM port 2 and virtual COM port 3 as the sequence count value Bnum; After the drive counter increments by 1, determine whether the current count value of the drive counter is equal to the sequence count value Bnum; if yes, clear the drive counter and return to step A1; otherwise, return to step A1.

[0035] In this embodiment, based on the driving counter used for port switching in step A3, each increment of 1 represents switching to the next port. Considering that if the count value continues to cycle in this way, it will lead to a very large count value and increasingly larger memory resource consumption; therefore, as Figure 3 As shown, the drive counter is reset to zero when all ports complete one cycle. The preferred reset criterion is the total number of physical COM ports 2 and virtual COM ports 3.

[0036] It should be noted that the drive counter starts counting from 0, so it will be decremented by 1 compared to the corresponding port, and then it will be cleared when it is just accumulated to Bnum.

[0037] Furthermore, in step A1: the scan count value An is: An=[1000000 / F / (sCOM+xCOM) / T]; Where F is the refresh frequency selected according to the scan interval duration Anum, sCOM is the number of physical COM ports 2, xCOM is the number of virtual COM ports 3, and T is the interrupt response time of the timer built into the display device; The calculated value of the scan count An needs to be rounded to the nearest integer.

[0038] In this embodiment, the display device typically executes programs using a microcontroller. Therefore, according to the microcontroller's conversion rules, the scan interval duration Anum is converted into a scan count value An. This requires considering the timer interrupt response time T built into the microcontroller in the display device, and the refresh frequency F selected based on the scan interval duration Anum. Thus, the formula An = [1000000 / F / (sCOM+xCOM) / T] is used, where 1000000 / F / (sCOM+xCOM) calculates the scan interval duration Anum (e.g., if F = 125Hz, sCOM+xCOM = 7, and 1000000 is a unit conversion of 1 second, then Anum = 1.142ms). Dividing this by the timer interrupt response time T (e.g., T = 125us) yields the scan count value An (e.g., rounded to the nearest integer, An = 9).

[0039] Furthermore, step A4 includes the following sub-steps: A41: Determine the power-down flag (Flag); when the power-down flag (Flag) is 1, execute sub-step A42; A42: Compare the information to be saved with the information stored in the power-down memory; if the information is the same, end this step; if the information is different, update the information stored in the power-down memory to the information to be saved, and then set the count value of the drive counter to Bnum-1.

[0040] In this embodiment, the unfolding process of step A4 is as follows: Figure 4 As shown, in addition to setting sub-step A41 for judging the power-down flag, sub-step A42 is also set to force the closure of all virtual COM ports 3 after the information saving event is executed, since the information saving event has already taken 3~3.5ms, there is no need to perform virtual COM port 3 rotation again, and it directly points to the first physical COM port 2.

[0041] Furthermore, sub-step A41 also includes: when the power-down flag is 1, setting the power-down flag to 0.

[0042] In this embodiment, when the power-down flag is 1, while executing sub-step A42, the power-down flag is simultaneously set to 0 to avoid repeating step A4 and wait for the next power-down.

[0043] Furthermore, in step A2: power failure detection includes: detecting whether the power supply voltage VDD is lower than a preset low voltage threshold; if so, then confirming power failure.

[0044] In this embodiment, the display device can determine whether there is a power outage by detecting the power supply voltage VDD. For example, if the display device is programmed by a microcontroller, it can determine whether there is a power outage by checking whether the power supply voltage VDD supplied to the microcontroller is lower than the low voltage threshold (e.g., the microcontroller's VDD is usually 5V, and a voltage below 3.9V indicates a power outage).

[0045] Furthermore, before executing step A3, close all entity COM ports 2.

[0046] In this embodiment, as Figure 3 As shown, before executing step A3, it is preferable to first close all physical COM ports 2 to ensure the accuracy of each port driver operation.

[0047] Example 2 A control system for a display device, comprising executing the aforementioned control method for a display device, including: Scan interval module 10: Configures the scan counter to ensure the scan interval duration Anum; Power failure detection module 20: used for power failure detection; Port module 30: used to configure physical COM port 2 and virtual COM port 3 in sequence; and to receive port output data, which corresponds one-to-one with the physical COM port 2; Port driver module 40: Configures a driver counter to cyclically obtain the scan interval duration Anum from the scan interval module 10 and scan the physical COM port 2 and virtual COM port 3 of the driver port module 30 in turn; Information storage module 50: When the port driver module 40 scans and drives to the first virtual COM port 3, it interacts with the power failure detection module 20 to determine whether information needs to be saved; and configures a power failure memory for information storage.

[0048] In this embodiment, a preferred embodiment of a control system for a display device is also proposed, such as... Figure 5 As shown, the scanning interval module 10 is used to execute, for example, the program related to step A1; the power failure detection module 20 is used to execute, for example, the program related to step A2; the port module 30 and the port driver module 40 are used to execute, for example, the program related to step A3; and the information storage module 50 is used to execute, for example, the program related to step A4. Thus, the display device can realize all the contents of a control method for a display device through this system (such as a microcontroller applied to the display device).

[0049] The control method of a display device according to an embodiment of the present invention, as well as other components and operations of the system, are known to those skilled in the art and will not be described in detail here.

[0050] In the description of this specification, references to terms such as "embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0051] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A control method for a display device, characterized in that: The display device configures physical COM ports one-to-one with the number of display devices and configures at least one virtual COM port according to the information storage duration; the display device distributes the time equally to each physical COM port and each virtual COM port according to the total scan duration of a single cycle to obtain the scan interval duration Anum; The display device scans and drives all the physical COM ports and all the virtual COM ports in turn according to the scanning interval duration Anum, and the scanning and driving order is: first drive all the physical COM ports in sequence, and then drive all the virtual COM ports in sequence. The display device performs power failure detection synchronously. When a power failure is confirmed and the device scans and drives to the first virtual COM port, the display device saves the information.

2. The control method for a display device according to claim 1, characterized in that: When the display device scans and drives the physical COM port, it drives the corresponding display device to work; When the display device scans and drives to the virtual COM port, a no-operation occurs.

3. The control method for a display device according to claim 1, characterized in that: The execution program of the display device includes the following steps: A1: Convert the scan interval duration Annum into a scan count value An, and count it using a scan counter. When the scan counter counts to the scan count value An, execute step A3. A2: Perform power failure detection. The power failure flag is set to 1 only when a power failure is confirmed; otherwise, the power failure flag is set to 0. A3: A drive counter is configured. Based on the current count value of the drive counter, the corresponding physical COM port or the virtual COM port is selected for driving. After the driving is completed, the drive counter is incremented by 1, and the process returns to step A1. When the first virtual COM port is driven, step A4 is executed synchronously; A4: Determine the power failure flag (Flag); when the power failure flag (Flag) is 1, save the information.

4. The control method for a display device according to claim 3, characterized in that: Step A3 further includes: configuring the total number of the physical COM ports and the virtual COM ports as a sequence count value Bnum; After the drive counter increments by 1, determine whether the current count value of the drive counter is equal to the sequence count value Bnum; if yes, clear the drive counter and return to step A1; otherwise, return to step A1.

5. The control method for a display device according to claim 3, characterized in that: In step A1: the scan count value An is: An=[1000000 / F / (sCOM+xCOM) / T]; Where F is the refresh frequency selected according to the scan interval duration Anum, sCOM is the number of physical COM ports, xCOM is the number of virtual COM ports, and T is the timer interrupt response time built into the display device; The calculated value of the scan count An needs to be rounded to the nearest integer.

6. The control method for a display device according to claim 4, characterized in that: Step A4 includes the following sub-steps: A41: Determine the power-down flag (Flag); when the power-down flag (Flag) is 1, execute sub-step A42; A42: Compare the information to be saved with the information stored in the power-off memory; If the information is the same, end this step; if the information is different, update the stored information in the power-down memory to the information to be saved, and then set the count value of the drive counter to Bnum-1.

7. The control method for a display device according to claim 6, characterized in that: The sub-step A41 further includes: when the power-down flag is 1, setting the power-down flag to 0.

8. The control method for a display device according to claim 3, characterized in that: In step A2: power failure detection includes: detecting whether the power supply voltage VDD is lower than a preset low voltage threshold; if so, then power failure is confirmed.

9. The control method for a display device according to claim 3, characterized in that: Before performing step A3, close all COM ports of the entity.

10. A control system for a display device, characterized in that: A control method for a display device according to any one of claims 1 to 9, comprising: Scan interval module: Configures a scan counter to ensure the scan interval duration Anum; Power failure detection module: used for power failure detection; Port module: used to configure the physical COM port and the virtual COM port in sequence; and to receive port output data, which corresponds one-to-one with the physical COM port; Port driver module: Configures a driver counter to cyclically obtain the scan interval duration Anum from the scan interval module, and scans the physical COM port and the virtual COM port that drive the port module in turn; Information storage module: When the port driver module scans and drives the first virtual COM port, it interacts with the power failure detection module to determine whether information needs to be stored; and configures a power failure memory for information storage.

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