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问 市面上的lcd太多了，而且接口各异。仅仅是SHARP自己产的屏就有好几种。
1• SHARP HR-TFT LQ039Q2DS53 (Default on the EVB)
2• SHARP CSTN LM057QCTT03 QVGA
3• SHARP TFT LQ057Q3DC02 VGA/QVGA
4• SHARP TFT LQ121S1DG31 800 × 600
5• SHARP TFT LQ104V1DG11 640 × 480

其中1接口需要50pins
    2接口需要15pins
    3接口需要33pins
    4接口需要41pins
    5接口需要31pins
除了我以上列的还有AD-TFT接口等等。

这些接口的本质区别到底在什么地方？
不会仅仅是在PIN的多少上吧？

许多ARM内置的lcd控制器在介绍上只提供颜色和分辨率参数，为什么不涉及接口呢？同样的颜色和分辨率，难道所有接口的LCD，ARM都支持吗？

期待。。





答 1: 接口不同没关系接口不同没关系,可以在CPU和LCD之间加驱动芯片,如果没有合适的驱动芯片就只能通过CPLD等可编程芯片自己生成LCD需要的时序了,一句话,如果CPU提供了LCD必要的信号(时序也符合),直接连接即可,否则就要加驱动了! 答 2: 我所指的都是内置LCD控制器的ARM如果还要在ARM和LCD间添加新的控制器，那不让内置的LCD控制器浪费了吗？
从时序上考虑，当然CPLD可以完成任何驱动，不过自行设计一个LCD控制器，可不是那么容易的吧？起码要周期扫描行列线，还要管理好偌大的显存！

楼上的认为接口没有决定因素吗？表面看来，我觉得接口和颜色分辨率有关系。可不敢肯定，因为同样的颜色和分辨率接口还有区别的！


答 3: 可以选择双接口LCD的ARM我知道一款ARM是双接口LCD的，也许对你有帮助。不防看一下，www.abcARM.com. 答 4: 我说的就是内置LCD控制器的ARM我说的就是内置LCD控制器的ARM,内置的控制器决定了能提供的LCD的类型、最大分辨率和颜色数，内置的控制器一般提供的都是行同步、帧同步，时钟信号和RGB数据总线等基本数据接口，而各个厂家的LCD接口五花八门，需要的信号也是各不一样，只好通过专用的芯片把内置控制器的输出变成它所需要的。 答 5: re其实无外VSYNC、HSYNC、PIXEL CLOCK和RGB数据线，然后就是驱动电压，虽然接口没有标准，但大同小异。RGB线的多少决定了颜色的深度。分辨率大小则是由处理器的处理能力决定的，和接口无关。 答 6: 请教楼上的如果接口没有标准，那vga和qvga又指的是什么？ 答 7: 终于在sharp的网站上找到了介绍http://www.sharpsma.com/lcd/lcdguide/Integration/TFT_LCD_interface.php


LCD panels unfortunately follow no uniform signal naming convention nor pin arrangement, so different LCD panels from different manufacturers will frequently have different pin arrangements and naming conventions. Pairing a Controller with an LCD will become much easier once the required types of signals CAN be known and understood. The table shows a TFT LCD signal and pin description from a tyPICal LCD manual. The example used here is the SHARP LQ057Q3DC02.
The interface signals follow three categories: control signals, data signals, and power connections.

• Control Signals: The example in the table shows control signals common to all LCD panels; again, they may differ by type and manufacturer.
• Clock signals (CK): for shifting RGB data into the LCD panel.
• Horizontal Synchronization signals (Hsync): There are ‘N’ number of CK periods per Hsync period where ‘N’ is the number of RGB pixels in a line. This signal marks the point at which the current line ends, and the new line begins.
• Vertical Synchronization signals (Vsync): There are ‘M’ number of Hsync periods per Vsync period where ‘M’ is the number of vertical lines in the display. This signal marks the point at which the current frame ends, and the new frame begins.

CK is the LCD’s clock source, a continuous squarewave. The frequency must be correct and within the panel’s specification to avoid flickering. The Horizontal Synchronization signal is a pulse that is activated when one line of data has been transmitted to the LCD. The Vertical Synchronization signal is a pulse that is activated when one page (or frame) of data has been transmitted to the LCD. The clock frequency must be correct and the Synchronization signal polarities must be correct, otherwise the image on the LCD will exhibit twisting or flickering.
Other control signals for this TFT LCD are:

• ENAB: Enable signal
• R/L: Right or Left sCAN direction select
• U/D: Up or Down sCAN direction select
• V/Q: VGA or QVGA select

The Enable signal enables the LCD; and so must be HIGH to enable the LCD display. Some control signals are specific to certain LCDs. In the sample above, R/L, U/D, V/Q signals must be tied to VCC or GND. They affect the image presentation (such as mirror imaging) and may not be available on all LCD panels.  
Data Signals The data signals are:

• Blue[5:0]
• Green[5:0]
• Red[5:0]

There are 18 data signals in total. They correspond to the LCD controller or LH79520 SoC output LCDVD[17] to LCDVD[0]. These signals are the LCD image data; they are active between the Horizontal Synchronization (Hsync) and Vertical Synchronization (VSync) pulses. Power Connections The LCD panel in this example requires VCC (3.3 V or 5 V) and GND.

LH79520's LCD Interface Pin Assignments

PIN NO. SYMBOL I/O FUNCTION 1 GND Ground 2 CK I Data Sampling Clock 3 HSync I Horizontal Synchronizing signal (negative-going) 4 VSync I Vertical Synchronizing signal (negative-going) 5 GND Ground 6 R0 I Red Data Signal (LSB) 7 R1 I Red Data Signal 8 R2 I Red Data Signal 9 R3 I Red Data Signal 10 R4 I Red Data Signal 11 R5 I Red Data Signal (MSB) 12 GND Ground 13 G0 I Green Data Signal (LSB) 14 G1 I Green Data Signal 15 G2 I Green Data Signal 16 G3 I Green Data Signal 17 G4 I Green Data Signal 18 G5 I Green Data Signal (MSB) 19 GND Ground 20 B0 I Blue Data Signal (LSB) 21 B1 I Blue Data Signal 22 B2 I Blue Data Signal 23 B3 I Blue Data Signal 24 B4 I Blue Data Signal 25 B5 I Blue Data Signal (MSB) 26 GND Ground 27 ENAB I Horizontal Display Position Set Signal 28 - 29 VCC +3.3 V Horizontal Display Direction Select Signal 30 R/L I L = Normal H = Reverse Vertical Display Direction Select Signal 31 U/D I L = Normal H = Reverse 32 V/Q I VGA/QVGA Mode Select Signal 33 GND Ground

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答 8: 各厂家都不同的,太多了,建议大家关注元太的LCD,性价比更高 答 9: reQVGA,VGA指分辨率，QVGA是320x240, VGA是640x480  答 10: 三星的怎么和你的不一样？

Resolution		Column		Row
VGA		640		480
SVGA		800		600
XGA		1024		768
SXGA		1280		1024
SXGA Plus		1400		1050
UXGA		1600		1200
WUXGA		1920		1200

答 11: 你说的VGA等接口...你说的VGA等接口，和LCD的接口不是一个接口。VGA接口差不错等于做了一个显示驱动模块，或者说显卡也可以，这个模块已经把MCU的信号处理了。如果你要做显示驱动模块的话，需要这个资料，如果是把MCU和LCD直接连接的话，没有必要。参考MCU关于LCD控制器的说明，和LCD的资料，连接就可以了。

MCU的资料上对于LCD的说明还是比较详细的。一般就R,B,G，位数，按照连接方式构成色数