Screen Parameter Configuration

1. Configuration File Introduction¶

The path of the config files in alkaid is project/board/ini/misc/config.ini

When the system starts, it will parse the config files, and then save the different screen parameters to the system and provide them to the display module. Then, according to the parameter setting of the user calling API, obtain the required screen parameters from the system.

The config files are composed of section and variable name:

• section：

  Fields in "[]" in the file.

• variable name：

  The field on the left of "=", and the assignment of variable name on the right.

The section is unique, and the same name is not allowed, but the variable name is allowed. As shown above, there can only be one section DACOUT_576I, but m_pPanelName can be in a different section. The system distinguishes variable names according to different sections, and then adds different screen parameters.

The variable name field is predefined by the system. When adding a new screen parameter, you can only fill in the existing ones in the system. Please inform the owner when adding or modifying it, otherwise the system will not recognize it. If the system definition is m_pPanelName, you can only use m_pPanelName to define a new panel name when adding.

An example of variable name assignment is as follows:

![](media/screen2.png

2. Add New Parameter¶

1. The defined new screen parameter section name cannot be the same as the existing one.

2. Add the section name of the new screen to the m_pnlList of the ROOT section (there can only be one LCD section with different interfaces, for example, there is a TTL panel section name in m_pnlList. If you want to add a new one, you can only delete the previous one.)

3. Add the new screen parameters to the new section:

   [SAT070AT50H18BH]
   m_pPanelName = "SAT070AT50H18BH_1024x600";
   m_bPanelDither = 0;
   m_ePanelLinkType = 0; #0:ttl 1:lvds 11:mipi
   
   m_bPanelInvDCLK = 0;
   m_bPanelInvDE = 0;
   m_bPanelInvHSync = 0;
   m_bPanelInvVSync = 0;
   
   m_wPanelHSyncWidth = 48;
   m_wPanelHSyncBackPorch = 46;
   m_wPanelVSyncWidth = 4;
   m_wPanelVBackPorch = 23;
   m_wPanelHStart = 98;
   m_wPanelVStart = 27;
   m_wPanelWidth = 1024;
   m_wPanelHeight = 600;
   
   m_wPanelHTotal = 1344;
   m_wPanelVTotal = 635;
   m_wPanelDCLK = 51;
   
   m_wSpreadSpectrumStep = 0;
   m_wSpreadSpectrumSpan = 0;
   
   m_eOutputFormatBitMode = 2; #0:10bit 1:6bit 2:8bit 3:565bit
   
   m_ucPanelSwapChnR = 3;
   m_ucPanelSwapChnG = 2;
   m_ucPanelSwapChnB = 1;
   m_ucPanelSwapRgbML = 1;
   

3. Parameter Description¶

If it is a MIPI panel, you need to configure MIPI DSI.

MIPI DSI parameter description:

Fill in the screen parameters according to the screen specification:

Timing related definition:

Timing definition and screen parameter parameters:

If it is a MIPI panel, you need to configure the MIPI AC timing related parameters. First, find the MIPI timing specification part in the panel specification.

UI calculation:

For example: $40ns+4 \times UI < HS-PREPARE < 85ns+6\times UI$ , the corresponding parameters in MIPI AC timing are as follows.

The calculation of other parameters in MIPI AC timing is the same as above.

Note:

The current screen parameter settings need to be updated: config_tool/mi_disp/mhal, if uboot pannel is involved, uboot needs to be updated.