VIM1S HDMI display blank screen issue

Technical Support
1

Hi
we are working on khadas VIM1S board with android 11 we are able to get HDMI display in normal 1080p display with resolution 1920x1080
but when we connected the 10.1 inch waveshare display to HDMI port display is in blank screen
please provide me the solution how to change the resolution

regards
vijay

2

Please provide the specifications for this screen. thanks！

3

Display specification
Size 10.1"
Resolution 1280×800.
Display Interface HDMI.
Display Panel IPS.
Viewing Angle 170°
Touch Type Capacitive.
Touch Points 10-point.
Touch Port USB.

4

@xiong.zhang Please follow up on this issue.

5

Hello,
Use the following adb command to send me the EDID of the monitor

cat /sys/class/amhdmitx/amhdmitx0/rawedid
6

Hi @xiong.zhang
after executing the command in shell output is

00ffffffffffff00048104000100000001110103800f0a000a00000000000000000000000000010101010101010101010101010101014c1d008050202d302830d3006c440000001800000010000000000000000000000000000000000010000000000000000000000000000000000010000000000000000000000000000000da

this is the EDID we are getting

7

Hello, you can try to compile the firmware after making the following modifications under bootloader/uboot and common.

xiong@server:/users/xiong/work/amlogic/vim1s/bootloader/uboot$ git diff
diff --git a/drivers/amlogic/media/vout/hdmitx/hdmitx20/hdmi_parameters.c b/drivers/amlogic/media/vout/hdmitx/hdmitx20/hdmi_parameters.c
index 8d411d149d..fba91b8efe 100644
--- a/drivers/amlogic/media/vout/hdmitx/hdmitx20/hdmi_parameters.c
+++ b/drivers/amlogic/media/vout/hdmitx/hdmitx20/hdmi_parameters.c
@@ -1604,22 +1604,22 @@ static struct hdmi_format_para fmt_para_vesa_1280x800p60_8x5 = {
        .tmds_clk = 83500,
        .timing = {
                .pixel_freq = 83500,
-               .h_freq = 49380,
-               .v_freq = 59910,
+               .h_freq = 49702,
+               .v_freq = 59810,
                .vsync_polarity = 1,
                .hsync_polarity = 1,
                .h_active = 1280,
-               .h_total = 1440,
-               .h_blank = 160,
-               .h_front = 48,
-               .h_sync = 32,
-               .h_back = 80,
+               .h_total = 1680,
+               .h_blank = 400,
+               .h_front = 72,
+               .h_sync = 128,
+               .h_back = 200,
                .v_active = 800,
-               .v_total = 823,
-               .v_blank = 23,
+               .v_total = 831,
+               .v_blank = 31,
                .v_front = 3,
                .v_sync = 6,
-               .v_back = 14,
+               .v_back = 22,
                .v_sync_ln = 1,
        },
 };

xiong@server:/users/xiong/work/amlogic/vim1s/common$ git diff
diff --git a/drivers/amlogic/media/vout/hdmitx/hdmi_common/hdmi_parameters.c b/drivers/amlogic/media/vout/hdmitx/hdmi_common/hdmi_parameters.c
index 7d1d151ad096..da2c746fc072 100644
--- a/drivers/amlogic/media/vout/hdmitx/hdmi_common/hdmi_parameters.c
+++ b/drivers/amlogic/media/vout/hdmitx/hdmi_common/hdmi_parameters.c
@@ -2272,23 +2272,23 @@ static struct hdmi_format_para fmt_para_vesa_1280x800p60_8x5 = {
        .tmds_clk = 83500,
        .timing = {
                .pixel_freq = 83500,
-               .h_freq = 49380,
-               .v_freq = 59910,
+               .h_freq = 49702,
+               .v_freq = 59810,
                .vsync = 60,
                .vsync_polarity = 1,
                .hsync_polarity = 1,
                .h_active = 1280,
-               .h_total = 1440,
-               .h_blank = 160,
-               .h_front = 48,
-               .h_sync = 32,
-               .h_back = 80,
+               .h_total = 1680,
+               .h_blank = 400,
+               .h_front = 72,
+               .h_sync = 128,
+               .h_back = 200,
                .v_active = 800,
-               .v_total = 823,
-               .v_blank = 23,
+               .v_total = 831,
+               .v_blank = 31,
                .v_front = 3,
                .v_sync = 6,
-               .v_back = 14,
+               .v_back = 22,
                .v_sync_ln = 1,
        },
        .hdmitx_vinfo = {
8

Try using this firmware

9

Hi @xiong.zhang

i have tried both changes in file and image you have given
but still the display is blank with 10.1 inch

10

Hello, because I see that there are very few EDID breaks, it may be a special screen. Could you please try it with Linux firmware to see if Linux firmware also has the same problem. We currently do not have this kind of resolution here. screen, you can try it first and then synchronize the information to me

11

Hi @xiong.zhang

with prebuilt Linux firmware image the display is working fine but with Android the display is blank

12

Okay, I’m going to modify it here.

13
14

@xiong.zhang Hi,
Still the Problem is same, the update.img is working normal monitor, but not working with 10
1" display ?

15

Hello, could you please grab the boot serial port log?

https://docs.khadas.com/products/sbc/vim1s/development/setup-serial-tool

16

@xiong.zhang please find the google link for log txt file

17

Sorry please find the link

18

Hello, because I don’t have a 1280x800 resolution monitor like yours, so I can only send you the modified firmware for you to try. I’m very sorry for causing you trouble. If it still doesn’t work, use the following firmware and download it again. Send me the boot log, thank you

19

Hi @xiong.zhang

Thank you so much for image now its working fine
can you share me the changes patch file so that i can adopt in my own android image

Regards
vijay

20

I uploaded the patch to the cloud. The directory inside is the corresponding path. Can you help me click to solve it and like it? Thank you. :grin:

https://drive.google.com/drive/folders/1YaGPVxuV7masLT5bp0TkLPq5xLZ_J6wX?usp=sharing

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