KR100466328B1 - Method for securing reliablity of Inter-Integrated Circuit communication - Google Patents

Abstract

In order to secure reliability in all fields using the I2C communication method, the present invention adds a stop condition (P) before the start condition (S) indicating the start of operation in the chip-to-chip communication using the I2C. The stop condition (P) restarts the MCU and other ICs to start operation under the same conditions each time, regardless of the state of the chips, to improve the IC-to-IC communication reliability of the I2C communication. It features.

Description

Method for securing reliablity of Inter-Integrated Circuit communication}

The present invention relates to inter-integrated circuit (I2C) communication, and more particularly, to a method for securing reliability of I2C communication for securing reliability in all electronic devices using I2C communication.

I2C is a method of chip-to-chip communication. It is a data line used for data transfer between devices, and can be communicated with two lines that transmit data and clock, respectively. Multiple masters can exist on the same bus at the same time.

Here, the two lines include a data line for transmitting serial data (SDA) and a clock line for transmitting a serial clock (SCL). Therefore, when the master transmits the clock through the clock line and the data and the address through the data line, the slave device (slave) synchronizes the clock and the data transmitted through the data line with the clock transmitted through the clock line. Will be received.

Referring to Figure 1 I2C having the above characteristics, as follows.

Fig. 1A is an operation timing diagram of I2C. When the clock signal SCL is high and the data signal CDA falls from a high state to a low state, the operation starts. The condition S is indicated and, on the contrary, when the data signal SDA goes from the low state to the high state while the clock signal SCL is high, it indicates the stop condition P which is the end of the operation. Fig. 1B is an operation timing diagram showing data transfer between a master device and a slave device (slave), wherein the clock signal SCL is mainly controlled by the master device, and the data signal SDA is a situation. According to the data transmission side, one transmission frame includes one or more address bytes or data bytes, a start condition (S), a stop condition (P), an operation (Ack), and a slave interrupt ( Slave interrupt). Start condition (S) and stop condition (P) conditions are controlled by the master device, and the operation condition (Ack) condition is controlled by the data receiving end, and it informs the transmitting end whether the normal data is received, and the slave interrupt is sent from the slave device to the master device. Used to send a wait signal.

Recently, the I2C communication method is widely used for communication between chips in digital parts of all other home appliances such as monitors, audio, computers, and the like. As one example, a monitor is a product in which an analog part and a digital part coexist. It has a variable that may cause a malfunction.

In general, the schematic flow using the I2C communication method will be briefly described as shown in FIG. When the power is turned on (200), the MCU, the X-TAL oscillator and other ICs are operated (210), and the chip address is set by the start condition (S) 220 indicating the start of operation in the chip-to-chip communication using I2C. Transmission 230 and receive data are transmitted 240, and the signal is terminated by the stop condition.

In the general flow as described above, there is a problem that a noise on the analog, for example, noise generated at power-on malfunctions the MCU and other ICs and causes an unpredictable defect.

As described above, noise is generated in the analog unit at power-on, and the digital unit may be in an unstable state where no one can predict, and may cause defects of various symptoms that cannot be predicted by anyone and can not be reproduced.

Accordingly, an object of the present invention is to solve the above problems, and an object thereof is to secure reliability of I2C communication so that a variable on an analog does not affect other ICs including the MCU of the digital unit.

The above and other objects and novel features of the present invention will become apparent from the description and the accompanying drawings.

1A is an operation timing diagram of I2C, (b) is an operation timing diagram between a master device and a slave device (slave),

2 is a schematic flow diagram using a conventional I2C communication method;

3 is a schematic flow diagram using an I2C communication method according to the present invention.

In order to achieve the above object, the present invention adds a stop condition (P) before the start condition (S) indicating the start of operation in the chip-to-chip communication using I2C in all the electronic device field using the I2C communication method, all chips The stop condition (P) restarts the MCU and other ICs to start operation under the same conditions each time, regardless of their previous state, thereby improving the reliability of IC-to-IC communication in I2C communication. It features.

The chip-to-chip communication method using I2C can be used in digital parts of monitors, audio, computers, and all other home appliances, but one embodiment of the present invention describes a monitor.

Hereinafter, with reference to the accompanying drawings the present invention will be described in detail. In addition, in all the drawings for demonstrating an Example, the same code | symbol is attached | subjected to the member which has the same function, and the description of the repetition is abbreviate | omitted.

For example, a monitor generally includes a digital unit such as an MCU, a deflection IC, a video preamp, and an EEPROM, and an analog unit such as a power, a deflection coil, a high voltage generator, and a CDT.

When the power is turned on or off in the analog unit, the noise is always generated. The noise also affects the digital unit including the MCU, which may cause a malfunction in the digital unit.

In the digital unit, data transmission in the communication between the chips implemented by the I2C communication method may occur in an unstable state unlike the normal state due to various noises generated during power on / off when the power is turned on / off. The state of the various ICs, such as and other devices, may be irregular, such that the clock signal (SCL) or data signal (SDA) of the I2C line configured as logic-and is not desired, for example, the data signal (SDA) is low. The monitor does not operate normally due to various malfunctions, such as changing from the high state to the high state but maintaining the low state. Therefore, add a stop command before I2C communication, that is, before transmitting the start condition (S). Restarts ICs that do not know what state the I2C line and MCU are in after power up but may be in an unstable state that can occur occasionally by stopping all commands. Sikimeuro can ensure the reliability of I2C communications.

As shown in Fig. 3, the flow is as follows.

When powered on (200), the MCU, X-TAL oscillator and other ICs will operate (210) and add a stop condition (P) 250 before the I2C communication so that the I2C line and MCU are not in what state. The ICs including the MCU in an unstable state due to the stop condition (P) 250 are restarted, and the chip address transmission 230 and the data are transmitted 240 by the start condition S 220 each time under a predetermined condition. In addition, since the signal is terminated by the stop condition, the reliability of the I2C communication can be secured.

In the above description, the invention mainly made by the present inventors described a monitor which is one of the background applications, but the present invention is not limited to this, but is implemented by the I2C communication method, for example, audio, computer, etc. Applicable to electronic devices.

As described above, the present invention adds the stop condition before the start condition (S) indicating the start of operation in the chip-to-chip communication using the I2C, due to the stop condition (P) regardless of the state of the previous state of all chips By restarting the MCU and other ICs to start the operation under the same conditions every time, the IC-to-IC communication reliability can be secured.

Claims (1)

In order to ensure reliability in all fields using I2C communication method, In the chip-to-chip communication using I2C, a stop condition (P) is added before the start condition (S) indicating the start of operation, due to the stop condition (P) regardless of what state the previous state of all chips is in. A method of securing reliability of I2C communication, characterized by improving the reliability of communication between IC chips of I2C communication by restarting the MCU and other ICs to start operation under the same conditions every time.