KR100833800B1 - Method for embodying bypass mode of multimedia chip - Google Patents

Abstract

The present invention relates to a method of implementing a bypass mode in a multimedia chip that can convert various types of data bits without special logic and more efficiently reduce power consumption when using the bypass mode in a multimedia chip. In a system consisting of a multimedia chip including a block and a host controlling the same, when the multimedia chip bypasses the LCD control signal of the host, the LCD is fixed at the host by fixing data bits to be extended for data bit expansion to fit the LCD. It is configured to allow only the data path of the direction.

Mobile, Multimedia Chip, LCD Controller, Bypass, Power Consumption, Expansion

Description

How to Implement Bypass Mode in Multimedia Chips {METHOD FOR EMBODYING BYPASS MODE OF MULTIMEDIA CHIP}

1 is a control structure diagram for performing an LCD display according to the prior art.

2A to 2E illustrate various types of data bit conversion methods applicable to LCDs according to the prior art.

3 is a diagram illustrating a data bus conversion logic when using a bypass mode in a multimedia chip according to the related art.

4A to 4E illustrate various types of data bit conversion methods applicable to LCDs according to the present invention.

5 is a diagram illustrating the data bus conversion logic when using the bypass mode in the multimedia chip according to the present invention.

※ Explanation of code about main part of drawing ※

100: host 200: multimedia chip

300: LCD 201: host interface

202: LCD interface 203 bit conversion logic

204: CPU

The present invention relates to a method of implementing a bypass mode in a multimedia chip that can convert various types of data bits without special logic and more efficiently reduce power consumption when using the bypass mode in a multimedia chip.

Multimedia chips, also known as backend chips, are being adopted for high-quality photo, music, and video functions that are too difficult to be implemented solely by the host of the mobile phone or the baseband chip.

In general, more than 90% of phones are used in bypass or standby mode, so how much power is consumed in bypass mode is the phone's main performance. Therefore, the core element of the multimedia chip is to operate at the minimum power in bypass mode. For this reason, multimedia chip manufacturers are exploring ways in which much of the logic can be powered down to reduce power loss when in bypass mode.

1 is a control structure diagram for performing an LCD display according to the related art, in which a host 10 controls a multimedia chip 20 or an LCD 30, and the multimedia chip 20 is connected to a host interface 21 and an LCD interface. And the host 10 controls the bypass on / off of the multimedia chip 20.

Referring to FIG. 1, the multimedia chip 20 has control of the LCD 30 when taking a picture or taking a video with a camera, or when viewing a downloaded video or viewing a picture. In other situations, that is, when the standby mode or a general menu operation is performed, the host 10 directly controls the LCD 30. Such an operation is referred to as a bypass mode. In other words, the signal from the host 10 reaches the LCD 30 by bypassing the multimedia chip 20. This bypass mode is used because the CPU interface method can be used without the need for complicated hardware to display simple menus.

On the other hand, the port used by the host 10 to control the multimedia chip 20 or the LCD 30 is an external I / O. In general, the data bus is 16 bits. On the other hand, the LCD 30 can be configured in various applications such as 16bit, 18bit, 24bit, etc. At this time, the method of extending 16bit to 18bit or 24bit varies for each LCD.

2A to 2E illustrate various types of data bit conversion methods applicable to LCDs according to the prior art, and FIGS. 2A to 2D show four methods of extending 16 bits to 18 bits. It shows how to extend 16bit to 24bit.

As such, since one method is selected from among various types of configuration methods and uses the bypass mode, the multimedia chip 20 converts the data bus transmitted from the host 10 as shown in FIG. 3. Bit conversion logic 23 is needed, and a register is also needed to help select this. In addition, the CPU 24 must set a register before entering bypass mode, and logic is required to automatically power down the CPU 24 and unnecessary blocks when the bypass mode is entered. As a result, this architecture requires very careful and complex control blocks, and system configuration is difficult because the LCD display can only be performed by setting a register for bypass by fast booting at startup.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to enable various types of data bit conversion without special logic when using the bypass mode in a multimedia chip, and to reduce power consumption more efficiently. It is to provide a bypass mode implementation method in.

In the bypass mode implementation method of the multimedia chip according to the present invention for achieving the above object, in the system consisting of an LCD, a multimedia chip including an LCD control block, and a host for controlling them, the LCD control signal of the host When the multimedia chip bypasses, the data bit to be extended is fixed to extend the data bit for the LCD so that only the data path in the LCD direction is possible in the host.

The data bits to be extended are data bits 16 to 23, and the data bits 16 to 23 are used as host interfaces.

In particular, when the bypass mode is off, the multimedia chip is characterized in that performing the data bit conversion in the LCD interface path.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

4A to 4E are diagrams illustrating various types of data bit conversion methods applicable to LCDs according to the present invention, and FIG. 5 is a diagram illustrating data bus conversion logic when using a bypass mode in a multimedia chip according to the present invention. to be.

The present invention has a technical feature to enable various types of data bit conversion as shown in FIGS. 2A to 2E without special logic, and the data bits to be extended 16 to 23 as shown in FIGS. 4A to 4E. By fixing the data bits and moving the bits according to the application, data bit conversion is not necessary for bypassing the multimedia chip.

However, as shown in FIG. 4E, when the expansion is performed in such a manner that two data bits are connected to one host bit, collision of different data values may occur in a path in which data of the LCD is read to the host. This problem can be solved by ensuring that data bits 16 to 23 used as HOST interfaces (I / F) in bypass mode always enable data paths from host to LCD.

Using data extension in this manner, bit conversion logic for the data path is unnecessary in the bypass mode of the multimedia chip as in the conventional FIG. Therefore, in the present invention, except that the host 100 selects the LCD control signal by bypass on / off, all the blocks can be turned off, so it is very efficient in terms of power consumption and easy to control power. .

However, when used as a normal display in which the bypass mode is off, the use method of FIGS. 4B to 4E has a problem that data bits are distorted. This can be solved by including the bit conversion logic 203 in the path of the LCD interface 202 as in FIG. That is, in the normal mode, since most of the logic including the CPU 204, the clock, and the like operate, power-down does not need to be greatly considered, and the bit conversion logic 203 is included here. For example, if the CPU 204 informs the register setting that it is in the form of FIG. 4B, the bit conversion logic 203 matches the output from the LCD interface 202 accordingly, i. The data is modified to be output and transferred to the LCD 300 side. This is also a way to shorten the time for the phone to register for display in bypass mode, which was a problem in the usual way above.

On the other hand, in the detailed description of the present invention has been described with respect to specific embodiments, various modifications are possible without departing from the scope of the invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims below, but also by the equivalents of the claims of the present invention.

As described above, according to the present invention, when the bypass mode is used in the multimedia chip, various kinds of data bits can be converted without special logic and power consumption can be easily reduced.

The present invention is also applicable to the chip embedded in the LCD controller including the host interface.

Claims (4)

In a system consisting of an LCD, a multimedia chip including an LCD control block, and a host controlling the LCD, when the multimedia chip bypasses the LCD control signal of the host, it is intended to expand for data bit expansion for the LCD. A method of implementing a bypass mode of a multimedia chip, in which data bits are fixed so that only a data path in the LCD direction is possible in the host. The method according to claim 1, A method of implementing a bypass mode of a multimedia chip, wherein the data direction of a host part among data bits to be extended is fixed in one direction, unlike a general data bus, thereby preventing collisions when data bits are expanded. The method according to claim 2, The data direction of the LCD portion of the data bits to be extended is the same as the general data bus, but the data content of the corresponding bit is not delivered to the host, the method of implementing the bypass mode of the multimedia chip, characterized in that it is used only in the chip. The method according to claim 1, And when the bypass mode is off, the multimedia chip performs data bit conversion in the LCD interface path.

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