VIM1S driving Waveshare 7.9" touchscreen

VIM1S
1

Which system do you use? Android, Ubuntu, OOWOW or others?

VOLUMIO_VERSION=“3.757”
VOLUMIO_HARDWARE=“vim1s”
VOLUMIO_DEVICENAME=“Khadas VIM1S”

Please describe your issue below:

Can’t get the display to work.
touch_input plugin is installed succesfuly, X is running.

Post a console log of your issue below:

I configured XRANDR according to the specifications found @ https://www.waveshare.com/wiki/7.9inch_HDMI_LCD

Pixel Clock H Adressable H Blanking V Adressable V Blanking H Front Porch H Sync Width V Front Porch V Sync Width H Image Size V Image Size H Border V Border
43.00 400 140 1280 42 70 10 20 10 60 191 0 0

Here’s the xrandr output

xrandr --verbose
Screen 0: minimum 320 x 200, current 1280 x 720, maximum 4096 x 4096
HDMI-1 connected primary (normal left inverted right x axis y axis)
	Identifier: 0x40
	Timestamp:  99150
	Subpixel:   unknown
	Clones:    
	CRTCs:      0
	Transform:  1.000000 0.000000 0.000000
	            0.000000 1.000000 0.000000
	            0.000000 0.000000 1.000000
	           filter: 
	EDID: 
		00ffffffffffff005e68333401000000
		14210103800000780a0dc9a057479827
		12484c00000001010101010101010101
		0101010101013417906a11001e50dc20
		aa003cbf000000183417906a11001e50
		dc20aa003cbf00000018000000fc0057
		61766573686172652d303739000000fd
		00147801ff1d000a202020202020013a
		02031a7147c646464646464623090701
		8301000065030c0010003417906a1100
		1e50dc20ca0c3cbf000000183417906a
		11001e50dc20aa003cbf000000183417
		906a11001e50dc20aa003cbf00000018
		3417906a11001e50dc20aa003cbf0000
		00180000000000000000000000000000
		00000000000000000000000000000063
	max bpc: 12 
		range: (8, 12)
	ready: 1 
		range: (0, 1)
	hdr_priority: 0 
		range: (0, -1)
	allm: 0 
		range: (0, 3)
	contenttype_cap: 1 
		range: (0, 1023)
	hdcp_mode: 0 
		range: (0, 36)
	hdcp_ver: 14 
		range: (0, 36)
	dv_cap: 0 
		range: (0, 1023)
	hdr_cap: 0 
		range: (0, 1023)
	hdmi_hdr_status: SDR 
		supported: HDR10Plus-VSIF, DolbyVision-Std, DolbyVision-Lowlatency, HDR10-GAMMA_ST2084, HDR10-others, HDR10-GAMMA_HLG, SDR
	MESON_DRM_HDMITX_PROP_AVMUTE: 0 
		range: (0, 1)
	color_space: RGB 
		supported: RGB, 422, 444, 420, HDMI_COLORSPACE_RESERVED6
	color_depth: 8 
		range: (0, 16)
	UPDATE: 0 
		range: (0, 1)
	vrr_capable: 0 
		range: (0, 1)
	content type: No Data 
		supported: No Data, Graphics, Photo, Cinema, Game
	HDCP Content Type: HDCP Type0 
		supported: HDCP Type0, HDCP Type1
	Content Protection: Desired 
		supported: Undesired, Desired, Enabled
	link-status: Good 
		supported: Good, Bad
	CONNECTOR_ID: 75 
		supported: 75
	non-desktop: 0 
		range: (0, 1)
  1280x720p100hz (0x42) 148.500MHz +HSync +VSync +preferred
        h: width  1280 start 1720 end 1760 total 1980 skew    0 clock  75.00KHz
        v: height  720 start  725 end  730 total  750           clock 100.00Hz
  dummy_l (0x43) 25.000MHz -HSync -VSync
        h: width   720 start  736 end  798 total  858 skew    0 clock  29.14KHz
        v: height  480 start  489 end  495 total  525           clock  55.50Hz
  400x1280 (0x3aa) 43.000MHz -HSync +VSync
        h: width   400 start  470 end  480 total  540 skew    0 clock  79.63KHz
        v: height 1280 start 1300 end 1310 total 1322           clock  60.23Hz

still, can’t get it to run.
When running

xrandr --output HDMI-1 --mode 400x1280

I get the following error :

xrandr: Configure crtc 0 failed

is there a way to configure hdmi timings at boot, like on a Pi ?

Thanks :wink:

2

Hello @jaostar

Looks like this resolution 400x1280 is not supported , and need to update kernel to support it.

3

If I can help you test, don’t hesitate to ask :wink:

4

Is there no EDID support ?

5

Amlogic kernels has this thing where it tries to filter out any HDMI modes that is not hard coded in the kernel. So even though your display is detected, all of its supported resolutions were being marked incompatible and hence the display doesn’t work. I have tried adding the display resolution information to the kernel based on the edid information you have posted above.

Could you please check the image here - 2024-12-26 - Google Drive. See if your display works with the same.

1 Like
6

Hello @numbqq

Are there any updates on this topic ?
Is there an updated kernel on the way ?

:wink:

7

@Jaostar, the above image that I shared via google drive contains the updated kernel. Did you got a chance to try it out? We were awaiting your feedback on the same

You can flash the image to a sdcard using balena etcher or raspberry pi imager. You can also try to flash it to emmc over lan using oowow

8

Hello,

Sorry, I work in a secured environment where downloading images from an unknown source google drive is a red flag :wink:
Your profile is quite new and you are not marked as trustworthy or as a Khadas dev… so I skipped your reply.

Nevertheless, I gave the image a try and I can see something that looks like the Khadas logo at boot… I think there are timing issues.

I made errors configuring the timings 2 weeks ago.
Here are the values with proper decoding of the EDID
( EDID Decode )

Preferred Video Timing if only Block 0 is parsed:
DTD 1: 400x1280 59.505921 Hz 5:16 77.953 kHz 59.400000 MHz (60 mm x 191 mm)
Hfront 220 Hsync 32 Hback 110 Hpol N
Vfront 10 Vsync 10 Vback 10 Vpol N

9

@jaostar

No problem, I would have probably done the same as well.

Yes, I have used the same. However I have only added changes to the kernel. Let me try adding changes to u-boot as well. Will share a new image in couple of days. Meanwhile can you share the output of following

cat /sys/class/drm/card*HDMI*/modes

You can enable ssh by visiting http://volumio.local/dev. Username and password is volumio