Ubuntu Desktop
Khadas official
When trying to enable the available UART with this information UART | Khadas Documentation, no /dev/ttyS4 device file is being creating
After trying a couple of other possible obvious device files, I gave up.
Please can you provide me accurate information about what should work?
Thanks.
Manfred
Edit file /boot/dtb/amlogic/kvim4.dtb.overlay.env add uart_e to node fdt_overlays=, save and reboot.
You will find node /dev/ttyS4.
Thanks a lot Nick for the quick response. Works like a charm now.
I seem to be having the same issue, however, the solution did not work for me. I have a VIM4 running an ubuntu 20.04 server image.
$ cat /boot/dtb/amlogic/kvim4.dtb.overlay.env
fdt_overlays=uart_e
$ ls /dev/ttyS*
/dev/ttyS0 /dev/ttyS1
$ ls /boot/dtb/amlogic/
kvim4.dtb kvim4.dtb.overlay.env
$ cat /boot/env.txt
#############################DO NOT TOUCH THIS OPTION#############################
rootdev=UUID=f596e1cf-584c-4859-a026-91a919bda4b1
#############################DO NOT TOUCH THIS OPTION#############################
# Cooling FAN mode
# auto - auto schedule the FAN speed depend on the CPU temperature
# low - FAN low speed
# mid - FAN middle speed
# high - FAN high speed
fan_mode=auto
# DMA coherent_pool size
# Don't touch unless you know what you are doing
dma_size=2M
# HDMI resolution auto detection
# yes - auto detection
# no - set HDMI resolution via 'hdmi' node
hdmi_autodetect=yes
# HDMI mode
# Resolution Configuration
# Symbol | Resolution
# ----------------------+-------------
# "480x272p60hz" | 480x272 Progressive 60Hz
# "480x320p60hz" | 480x320 Progressive 60Hz
# "480p60hz" | 720x480 Progressive 60Hz
# "576p50hz" | 720x576 Progressive 50Hz
# "720p60hz" | 1280x720 Progressive 60Hz
# "720p50hz" | 1280x720 Progressive 50Hz
# "1080p60hz" | 1920x1080 Progressive 60Hz
# "1080p50hz" | 1920x1080 Progressive 50Hz
# "1080p30hz" | 1920x1080 Progressive 30Hz
# "1080p24hz" | 1920x1080 Progressive 24Hz
# "1080i60hz" | 1920x1080 Interlaced 60Hz
# "1080i50hz" | 1920x1080 Interlaced 50Hz
# "2160p60hz" | 3840x2160 Progressive 60Hz
# "2160p50hz" | 3840x2160 Progressive 50Hz
# "2160p30hz" | 3840x2160 Progressive 30Hz
# "2160p25hz" | 3840x2160 Progressive 25Hz
# "2160p24hz" | 3840x2160 Progressive 24Hz
# "smpte24hz" | 3840x2160 Progressive 24Hz SMPTE
# "2160p60hz420" | 3840x2160 Progressive 60Hz YCbCr 4:2:0
# "2160p50hz420" | 3840x2160 Progressive 50Hz YCbCr 4:2:0
# "640x480p60hz" | 640x480 Progressive 60Hz
# "800x480p60hz" | 800x480 Progressive 60Hz
# "800x600p60hz" | 800x600 Progressive 60Hz
# "1024x600p60hz" | 1024x600 Progressive 60Hz
# "1024x768p60hz" | 1024x768 Progressive 60Hz
# "1280x800p60hz" | 1280x800 Progressive 60Hz
# "1280x1024p60hz" | 1280x1024 Progressive 60Hz
# "1360x768p60hz" | 1360x768 Progressive 60Hz
# "1440x900p60hz" | 1440x900 Progressive 60Hz
# "1600x900p60hz" | 1600x900 Progressive 60Hz
# "1600x1200p60hz" | 1600x1200 Progressive 60Hz
# "1680x1050p60hz" | 1680x1050 Progressive 60Hz
# "1920x1200p60hz" | 1920x1200 Progressive 60Hz
# "2560x1080p60hz" | 2560x1080 Progressive 60Hz
# "2560x1440p60hz" | 2560x1440 Progressive 60Hz
# "2560x1600p60hz" | 2560x1600 Progressive 60Hz
# "3440x1440p60hz" | 3440x1440 Progressive 60Hz
hdmi=720p60hz
# Specify the log level
# 2 - default, output both kernel logs & system logs
# 1 - only output system logs
# 0 - disable all output logs
loglevel=2
# Setup splash
# true - enable splash
# false - disable splash
enable_splash=true
# User kernel args
# Add customer kernel args here
user_kernel_args=
# Framebuffer Rotate
# 0 - default
# 1 - clockwise, 90 degrees
# 2 - clockwise, 180 degrees
# 3 - clockwise, 270 degrees
fb_rotate=0
# Device Tree Overlays
# uart3 -- Enable UART3 (uart_C, GPIO Header PIN15 & PIN16)
# pwm_f -- Enable PWM_F (GPIO Header PIN35)
# i2c3 -- Enable i2c3 (GPIO Header PIN22 & PIN23)
# spi1 -- Enable SPI1 (GPIO Header PIN15 & PIN16 & PIN35 & PIN37), pwm_f need to be removed
# i2s -- Enable I2S (GPIO Header PIN29 & PIN30 & PIN31 & PIN32 & PIN33)
# os08a10 -- Enable OS08A10 Camera
# onewire -- Enable onewire bus (GPIO Header PIN15)
# disable-ts050 -- Disable TS050 LCD
# m2x-eth -- Enable M2X 100M ethernet. Note: 1G ethernet will be disabled.
# otg-device -- Enable USB OTG Device
# watchdog -- Enable watchdog
#overlays=uart3 pwm_f i2c3 i2s os08a10 watchdog
overlays=uart4 disable-ts050
@nkhedekar the overlay name is wrong, its uart_e.
Also it must be applied in overlays/kvim4.dtb.overlay.env, not in boot/env.txt, Kernel arguments in vim4 are only read from uEnv.txt file.
please retry and check.
Hi @Electr1 , maybe I am missing something. I have already added fdt_overlays=uart_e in the /boot/dtb/amlogic/kvim4.dtb.overlay.env but that does not seem to work. Is there another file that needs to be modified? Also, where can one find the uEnv.txt file?
I also tried changing the last line of the /boot/env.txt to overlays=uart_e disable-ts050, but that did not have any effect either.
We don’t maintain ubuntu 20.04, please use the ubuntu 22.04 images.
