DS90UB949-Q1: When DS90UB949-Q1 is used in combination with DS90UB948-Q1, the display screen has no content display

Ds90ub949-q1 is used with DS90UB948-Q1,hdmi output to ds90ub949, 948 output to screen， the screen is not displayed but the backlight of the screen is bright, and i2c can communicate with Ds90ub949-q1 and S90UB948-Q1.
T he pattern test is performed, the screen is also not displayed.

Perform the configuration according to 4.4 Cases in the SNLA132G document. Use the Without FPD-link III scheme and configure 948 to enter Pattern test. The screen displays no information.
code show as below：
{
//1. Set Pixel Clock and Active Frame Size 1920
ds90ub948_single_write(ds90ub948, 0x66, 0x07);
ds90ub948_single_write(ds90ub948, 0x67, 0x80);
ds90ub948_single_write(ds90ub948, 0x66, 0x08);
ds90ub948_single_write(ds90ub948, 0x67, 0x87);
ds90ub948_single_write(ds90ub948, 0x66, 0x09);
ds90ub948_single_write(ds90ub948, 0x67, 0x43);
//2. Set Total Frame Size 2200 ds90ub948_single_write(ds90ub948, 0x66, 0x04);
ds90ub948_single_write(ds90ub948, 0x67, 0x98);
ds90ub948_single_write(ds90ub948, 0x66, 0x05);
ds90ub948_single_write(ds90ub948, 0x67, 0x58);
ds90ub948_single_write(ds90ub948, 0x66, 0x06);
ds90ub948_single_write(ds90ub948, 0x67, 0x46);
//3. Set Back Porch ds90ub948_single_write(ds90ub948, 0x66, 0x0C);
ds90ub948_single_write(ds90ub948, 0x67, 0x94);
ds90ub948_single_write(ds90ub948, 0x66, 0x0D);
ds90ub948_single_write(ds90ub948, 0x67, 0x24);
//4. Set Sync Width
ds90ub949_single_write(ds90ub948, 0x66, 0x0A);
ds90ub949_single_write(ds90ub948, 0x67, 0x2C);
ds90ub948_single_write(ds90ub948, 0x66, 0x0B);
ds90ub948_single_write(ds90ub948, 0x67, 0x05);
//5.Set Sync Polarities
ds90ub948_single_write(ds90ub948, 0x66, 0x0E);
ds90ub948_single_write(ds90ub948, 0x67, 0x00);
//6.Enable Pattern Generation
ds90ub948_single_write(ds90ub948, 0x65, 0x0C);
ds90ub948_single_write(ds90ub948, 0x64, 0x05);
}
How should I judge the problem?How to make patgen work only on deserializers before using patgen via FPD-Link?
Please give me a reply. Thank you very much

Kailyn Chen：

您好，这个问题我需要在看下资料 ，尽快给您答复。

,

ivan li：

这个是我屏的参数

,

Kailyn Chen：

抱歉，上周请假了现在才给您回复。

为了更好的解决您的问题，我刚已经上传到英文E2E了，请关注他们的回复：

https://e2e.ti.com/support/interface-group/interface/f/interface-forum/1229072/ds90ub948-q1-when-ds90ub949-q1-is-used-in-combination-with-ds90ub948-q1-the-display-screen-has-no-content-display

如有任何问题，可以直接在英文E2E上或者这里跟进都可以的。

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Kailyn Chen：

您好，您这边看到E2E给的回复了吗：

您配置的pattern 分辨率是1920x1080p，并且enable 外部clock模式。

Htotal: 2200

Vtotal: 1125

HActive: 1920

VActive: 1080

HBP: 148

VBP: 24

HSW: 44

VSW: 5

Positive polarity.

但是这个配置和屏幕的参数是不匹配的。

ivan li 说：How to make patgen work only on deserializers before using patgen via FPD-Link?

按照您当前的配置就是只在解串器端，这个配置是没有pattern从ser端输出来的。如果需要的话，可以配置SER端 使能pattern。

需要注意因为您已经enable 外部clock模式，那么948会期望来自于ser端的PCLK。所以如果949端没有HDMI输入的话，您需要更改为内部clock模式。

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ivan li：

如你说所，是因为分辨率配置错误导致

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Kailyn Chen：

感谢您的反馈。 那我就把这个帖子关闭了。