KR20250034795A - Method And Apparatus for Performing Telecommunications Based On I2C - Google Patents

Abstract

A communication method and device based on I2C are disclosed.
According to one aspect of the present disclosure, a method for implementing I2C communication is provided, the method including a transmitting process in which a master microcontroller unit (hereinafter, “MMCU”) transmits an SCL signal; a monitoring process in which the MMCU monitors a voltage of a first SCL line; and a determining process in which, when the voltage of the first SCL line is greater than or equal to a threshold value, the MMCU determines that an ACK signal has been received.

Description

{Method And Apparatus for Performing Telecommunications Based On I2C}

The present disclosure relates to a communication method and device based on I2C. More specifically, it relates to a communication method and device based on I2C using GMSL SerDes.

The content described below merely provides background information related to the present embodiment and does not constitute prior art.

I2C (inter integrated circuit) is one of the communication methods used for communication between devices included in an embedded system, such as integrated circuits. I2C is used for communication between one master device and at least one slave device. I2C connects a master device and a slave device using a serial data (SDA) line and a clock (SCL) line, and performs communication between the master device and the slave device by applying signals to the SDA line and the SCL line.

This I2C can be performed using GMSL SerDes technology (gigabit multimedia serial link serializer and deserializer technology, hereinafter referred to as “GMSL”). GMSL is a technology that can quickly send and receive various signals using a multiplexer (mux) and a demultiplexer (demux). GMSL can send and receive signals in the forward direction and the reverse direction. For example, when I2C is performed using GMSL, the direction in which the master device sends a signal to the slave device is the forward direction.

When performing I2C communication using GMSL, if the time interval between the start signal and the stop signal is shorter than a specific time, GMSL disconnects the SCL and SDA connections after transmitting the 8th SCL signal. In addition, GMSL is grounded through a pull-down resistance. In other words, I2C communication between the master device and the slave device is disconnected. When the slave device sends an ACK signal to the deserializer, GMSL resumes the SCL and SDA connections and releases the ground state.

If the time interval between the start signal and the stop signal is shorter than a specific time, the SCL line connected to the master device may indicate an unknown state instead of low even though the slave device has not transmitted an ACK signal. In addition, there is a problem that the master device must wait in a high state before receiving an ACK, but waits in an unknown state. Due to the above-described problems, an error may occur in which the master device incorrectly recognizes that an ACK signal has been received even though it has not been received.

A communication method and device according to one embodiment of the present disclosure can eliminate an error that occurs when a time interval between a start signal and an end signal is shorter than a specific time.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to one aspect of the present disclosure, a method for implementing I2C communication is provided, the method including a transmitting process in which a master microcontroller unit (hereinafter, “MMCU”) transmits an SCL signal; a monitoring process in which the MMCU monitors a voltage of a first SCL line; and a determining process in which, when the voltage of the first SCL line is greater than or equal to a threshold value, the MMCU determines that an ACK signal has been received.

According to another aspect of the present disclosure, a communication device for I2C communication is provided, including: a master microcontroller unit (hereinafter, “MMCU”) for transmitting an SCL signal and monitoring a voltage of a first SCL line using an AD line; a slave microcontroller unit (hereinafter, “SMCU”) for receiving the SCL signal and transmitting an ACK signal; a serializer connected to the MMCU using the first SCL line; and a deserializer communicating with the serializer using GMSL technology and connected to the SMCU using a second SCL line, wherein the MMCU monitors the voltage of the first SCL line after transmitting 8 pulses to determine whether an ACK signal has been received.

According to one embodiment of the present disclosure, there is an effect that an error occurring when the time interval between a start signal and an end signal is shorter than a specific time can be eliminated by monitoring the voltage of the SCL line.

The effects of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

FIG. 1 is a block diagram schematically illustrating a GMSL device for I2C communication according to one embodiment of the present disclosure.
FIG. 2 is a diagram for explaining the configuration of MMCU and Ser according to one embodiment of the present disclosure.
FIG. 3 is a diagram for explaining the configuration of SMCU and Des according to one embodiment of the present disclosure.
FIG. 4 is a flowchart illustrating a process of performing 8-bit data transmission and reception using I2C according to one embodiment of the present disclosure.

Hereinafter, some embodiments of the present disclosure will be described in detail using exemplary drawings. When adding reference numerals to components in each drawing, it should be noted that the same components are given the same numerals as much as possible even if they are shown in different drawings. In addition, when describing the present disclosure, if it is determined that a specific description of a related known configuration or function may obscure the gist of the present disclosure, the detailed description thereof will be omitted.

In describing components of embodiments according to the present disclosure, symbols such as first, second, i), ii), a), b), etc. may be used. These symbols are only for distinguishing the components from other components, and the nature or order or sequence of the components is not limited by the symbols. When a part in the specification is said to "include" or "provide" a component, this does not mean that other components are excluded, but rather that other components can be further included, unless explicitly stated otherwise.

The detailed description set forth below, together with the accompanying drawings, is intended to explain exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure may be practiced.

I2C communication is a communication between a master device and a slave device using the SDA line and SCL line. Here, the SDA line and SCL line are open It is an open-drain line. That is, SDA and SCL use a wired-and connection. A wired-and connection means that if either of the two connected devices outputs 0 or low, the signal of the line connecting the two devices becomes 0 or low. In other words, it is a connection method in which the signal of the line connecting the two devices becomes 1 or high only when both connected devices output 1 or high.

A master device can use I2C to send, for example, an 8-bit signal to a slave device. The master device outputs 8 pulses to the SCL line, and then outputs a high signal. The master device waits for the slave device to output a high signal, and then outputs a pulse again when the slave device outputs a high signal. This high signal from the slave device is called an ACK (acknowledgement) signal.

According to one embodiment of the present disclosure, a communication device for I2C communication capable of preventing an ACK error is provided.

FIG. 1 is a block diagram schematically illustrating a GMSL device for I2C communication according to one embodiment of the present disclosure.

Referring to FIG. 1, a gigabit multimedia serial link device for inter integrated circuit telecommunication (GMSL) device for I2C communication (10) includes all or part of a master microcontroller unit (100), a serializer (110), a slave microcontroller unit (130), and a deserializer (120).

The GMSL device (10) for I2C communication according to the present disclosure may further include various components in addition to the components illustrated in FIG. 1. For example, the GMSL device (10) for I2C communication according to the present disclosure may further include a plurality of resistors, a plurality of power supplies, an SCL line, an SDA line, an AD line, and a GMSL line for connecting each component. In other words, the components of the GMSL device (10) for I2C communication according to the present disclosure are not limited to those illustrated in FIG. 1.

According to one embodiment of the present disclosure, components of a GMSL device (10) for I2C communication are connected to each other using various types of lines. Hereinafter, the term “line” does not mean only a physical line, but includes all means for transmitting or receiving electrical signals, etc. by connecting at least two terminals to each other.

According to one embodiment of the present disclosure, a master microcontroller unit (100, hereinafter, “MMCU”) can transmit an SCL signal and an SDA signal for I2C communication, and can receive an ACK signal. A slave microcontroller unit (130, hereinafter, “SMCU”) can receive an SCL signal and an SDA signal for I2C communication, and can transmit an ACK signal. According to one embodiment of the present disclosure, generation and transmission of the SDA signal are performed in the same manner as in the known I2C communication. Therefore, a description of the SDA signal is omitted below.

MMCU (100) is connected using Ser (110) and SCL lines.

Below, with reference to Fig. 2, the connection method and configuration of MMCU (100) and Ser (110) are described.

FIG. 2 is a diagram for explaining the configuration of MMCU and Ser according to one embodiment of the present disclosure.

Referring to Fig. 2, MMCU (100) is connected to Ser (110) using the first SCL line (200). MMCU (100) and Ser (110) receive and transmit SCL signals using the first SCL line (200). MMCU (100) transmits an SCL signal to Ser (110), and Ser (110) transmits an SCL signal to Des (120) using GMSL line (12).

The first SCL line (200) is connected to an AD line (analog to digital line, 210). The AD line (210) is a line connected to the MMCU (100), power, the first SCL line (200), and at least two resistors. At least one resistor connected to the AD line (210) is a pull-up resistor (220).

The other resistor (230) may have a predefined resistance value. The resistance value of the other resistor (230) may be defined by considering, for example, the internal pull-down resistance of the MMCU, the current limit of the AD terminal, and the sampling time due to passive components.

The power supply supplies power to the first SCL line (200) and the AD line (210). The power supply may have a voltage of, for example, 3.3 V.

Since pull-up resistors are a common and well-known element in I2C communication, a detailed description of them is omitted.

The MMCU (100) can monitor the SCL state of the first SCL line (200) using the AD line (210). The MMCU (100) can monitor the SCL state by monitoring the voltage using the AD line (210). Here, the SCL state includes whether the SCL signal is a high signal or a low signal.

The AD line (210) is a line for monitoring the voltage of the first SCL line (200). The AD line (210) can monitor the voltage by dividing it into 8 bits, 10 bits, or 12 bits depending on the input from outside the device. When monitoring the voltage using a GPIO (general purpose input and output) line, it is only possible to distinguish whether the voltage is greater than a specific value or less than a specific value. However, by using the AD line (210), the voltage value can be monitored in more detail. That is, by using the AD line (210), the SCL status can be monitored more accurately.

Des (120) is connected to a serializer (110, hereinafter, “Ser”) using a GMSL line (12). Ser (110) transmits an SCL signal to Des (120) using the GMSL line (12).

The SMCU (130) and the deserializer (120, hereinafter “Des”) are connected to each other using the second SCL line (300). The second SCL line (300) is a line for transmitting and receiving SCL signals.

Below, with reference to Fig. 3, the connection method and configuration of SMCU (130) and Des (120) are described.

FIG. 3 is a diagram for explaining the configuration of SMCU and Des according to one embodiment of the present disclosure.

Referring to Fig. 3, SMCU (130) is connected to Des (120) using a second SCL line (second SCL line, 300). SMCU (130) receives an SCL signal from Des (120) using the second SCL line (300) and transmits an SCL signal to Des (120).

At least one resistor connected to the second SCL line (300) is a pull-up resistor (310). A power source supplies power to the second SCL line (300). The power source may have a voltage of, for example, 3.3 V.

FIG. 4 is a flowchart illustrating a process of performing 8-bit data transmission and reception using I2C according to one embodiment of the present disclosure.

Referring to FIG. 4, the MMCU (100) transmits an SCL signal (S400). According to one embodiment of the present disclosure, the SCL signal may include eight pulses. In other words, the MMCU (100) may transmit eight high signals and eight low signals. The MMCU (100) may transmit the high signals and the low signals alternately.

After transmitting 8 pulses, the MMCU (100) waits in a high state (S410). That is, it continuously transmits a 'high' SCL signal. Here, the high state of the MMCU (100) is a state of waiting for an ACK signal from the SMCU (130), and continues until the first SCL line (200) indicates a high signal.

After transmitting eight pulses, the MMCU (100) monitors the voltage of the first SCL line (200) using the AD line (210) (S420).

The MMCU (100) compares the voltage of the first SCL line (200) with a predefined threshold value (S430).

If the voltage of the first SCL line (200) is greater than or equal to a predefined threshold value, the MMCU (100) determines that the first SCL line (200) is indicating a high signal (S430).

If the voltage of the first SCL line (200) is lower than a predefined threshold value, the MMCU (100) determines that the first SCL line (200) indicates a low signal (S440). If it is determined that the first SCL line (200) indicates a low signal, the MMCU (100) determines that it has not yet received an ACK signal. If it has not received an ACK signal, the MMCU (100) maintains a high state and waits. If it has not received an ACK signal, the MMCU (100) continuously monitors the voltage of the first SCL line (200) using the AD line (210).

If it is determined that the first SCL line (200) indicates a high signal, the MMCU (100) determines that an ACK signal has been received (S450).

When the MMCU (100) receives an ACK signal, the MMCU (100) determines that the transmission and reception of 8-bit data using I2C has been completed (S460).

The flowchart illustrated in Fig. 4 illustrates a process in which the MMCU (100) transmits 8-bit data in the I2C manner. The MMCU (100) can repeat the process illustrated in Fig. 4 to transmit data larger than 8 bits. When the MMCU (100) determines that the transmission and reception of 8-bit data is complete, it can transmit the next 8-bit data using I2C. That is, the processes S400 to S460 can be repeated.

According to one embodiment of the present disclosure, after the SMCU (130) receives eight SCL pulses, the MMCU (100) waits in a high state. That is, after the MMCU (100) transmits an 8-bit signal, it can receive an ACK signal from the SMCU (130). Therefore, the I2C topology can be satisfied even though the GMSL is used.

According to one embodiment of the present disclosure, the voltage can be monitored using the AD line (210), and a high signal or a low signal of the first SCL line (200) can be distinguished using a predefined threshold value. Accordingly, even when the time interval between the start signal and the stop signal is short, it is possible to prevent incorrect recognition of the ACK signal. That is, even though the SMCU (130) does not output the ACK signal, it is possible to prevent a situation in which the MMCU (100) recognizes a low-voltage SCL signal as an ACK signal due to the SCL connection between Ser (110) and Des (120) being disconnected.

Each component of the device or method according to the present invention may be implemented as hardware or software, or as a combination of hardware and software. In addition, the function of each component may be implemented as software, and the microprocessor may be implemented to execute the function of the software corresponding to each component.

Various implementations of the systems and techniques described herein can be implemented as digital electronic circuits, integrated circuits, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), computer hardware, firmware, software, and/or combinations thereof. These various implementations can include implementations of one or more computer programs executable on a programmable system. The programmable system includes at least one programmable processor (which may be a special purpose processor or a general purpose processor) coupled to receive data and instructions from, and transmit data and instructions to, a storage system, at least one input device, and at least one output device. Computer programs (also known as programs, software, software applications, or code) include instructions for the programmable processor and are stored on a "computer-readable medium."

A computer-readable recording medium includes any type of recording device that stores data that can be read by a computer system. Such a computer-readable recording medium can be a non-volatile or non-transitory medium, such as a ROM, a CD-ROM, a magnetic tape, a floppy disk, a memory card, a hard disk, a magneto-optical disk, a storage device, and may further include a transitory medium, such as a data transmission medium. In addition, the computer-readable recording medium can be distributed over a network-connected computer system, so that the computer-readable code can be stored and executed in a distributed manner.

Although the flowchart/timing diagram of this specification describes each process as being executed sequentially, this is only an illustrative description of the technical idea of one embodiment of the present disclosure. In other words, a person having ordinary skill in the art to which one embodiment of the present disclosure belongs may change and modify and apply various modifications and variations such as changing the order described in the flowchart/timing diagram and executing it or executing one or more of the processes in parallel without departing from the essential characteristics of one embodiment of the present disclosure. Therefore, the flowchart/timing diagram is not limited to a chronological order.

The above description is merely an illustrative description of the technical idea of the present embodiment, and those with ordinary skill in the art to which the present embodiment pertains may make various modifications and variations without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical idea of the present embodiment but to explain it, and the scope of the technical idea of the present embodiment is not limited by these embodiments. The protection scope of the present embodiment should be interpreted by the following claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of the rights of the present embodiment.

100: Master Microcontroller Unit
110: Serializer 120: Deserializer
130: Slave Microcontroller Unit

Claims (10)

In a method for implementing I2C communication,
A transmission process in which the master microcontroller unit (hereinafter “MMCU”) transmits an SCL signal;
A monitoring process in which the above MMCU monitors the voltage of the first SCL line; and
If the voltage of the first SCL line above is greater than or equal to the threshold value, the MMCU determines that it has received an ACK signal.
A method including: In the first paragraph,
The above MMCU completes the completion confirmation process by determining that transmission and reception of data of a preset size has been completed when the above ACK signal is received.
How to include more. In the first paragraph,
A method further comprising a waiting process of waiting in a high state when the MMCU transmits the SCL signal including 8 pulses. In the first paragraph,
The above monitoring process is,
A method comprising: the MMCU monitoring the voltage of the first SCL line using the AD line. In the first paragraph,
The above transmission process is,
A method comprising a process in which the MMCU transmits the SCL signal using a serializer. In the third paragraph,
The above waiting process is,
A process for determining that the MMCU has not received the ACK signal when the voltage of the first SCL line is less than the threshold value.
A method comprising: A master microcontroller unit (hereinafter, “MMCU”) for transmitting an SCL signal and monitoring the voltage of the first SCL line using an AD line;
A slave microcontroller unit (hereinafter, “SMCU”) for receiving the above SCL signal and transmitting an ACK signal;
A serializer connected using the above MMCU and the first SCL line; and
A deserializer that communicates with the serializer using GMSL technology and is connected to the SMCU using a second SCL line.
Including, but not limited to,
The above MMCU is a communication device for I2C communication, which checks whether the ACK signal has been received by monitoring the voltage of the first SCL line after transmitting eight pulses. In Article 7,
The above MMCU is a communication device for I2C communication, which determines that the ACK signal has been received if the voltage of the first SCL line is greater than or equal to a predefined threshold value. In Article 7,
Including multiple resistors,
A communication device for I2C communication, wherein at least one of the plurality of resistors is a resistor connected to the AD line, and at least two of the resistors excluding the resistor connected to the AD line are pull-up resistors. In Article 8,
The above MMCU,
A communication device for I2C communication, which determines that the ACK signal has not been received and waits in a high state if the voltage of the first SCL line is less than a predefined threshold value.

Images