Difference between revisions of "Rockpi4/dev/use-uart-with-kernel-5.10"

Revision as of 09:05, 16 May 2022

    ROCK Pi 4 >  Development >  Use Uart with Kernel 5.10

If you want to use uart with Kernel 5.10 in ROCK Pi 4. You'd better follow these steps.

 sudo apt-get install -y rockpi4-dtbo

Modify file /boot/hw_intfc.conf. Set "on" to enable the optional hardware interfaces while set "off" to disable.

 intfc:uart2=on
 intfc:uart4=on

And add "#" to line "intfc:dtoverlay=console-on-ttyS2"

 #intfc:dtoverlay=console-on-ttyS2
 #intfc:dtoverlay=console-on-ttyS4

but now, the uart2 can still be used as a debug port with system log. If you don't want to output kernel messages, you can disable it as follow.

Modify file /boot/extlinux/extlinux.conf.

 append earlyprintk rw init=/sbin/init rootfstype=ext4 rootwait  root=UUID=8650cdca-49b0-4431-9667-5c639f6bab89

@@ Line 7: / Line 7: @@
 ===Description===
-ADB is enabled in ROCK Pi 4 all Android version and official Linux distributions. To access ADB, you need a USB male A to A cable(Upper USB3 port) and turn the USB OTG switch to Device mode.
+If you want to use uart with Kernel 5.10 in ROCK Pi 4. You'd better follow these steps.
-You'd better follow the installation steps.
+==== Install essential package ====
+  sudo apt-get install -y rockpi4-dtbo
+==== UART ====
+Modify file /boot/hw_intfc.conf. Set "on" to enable the optional hardware interfaces while set "off" to disable.
+  intfc:uart2=on
+  intfc:uart4=on
+And add "#" to line "intfc:dtoverlay=console-on-ttyS2"
+  #intfc:dtoverlay=console-on-ttyS2
+  #intfc:dtoverlay=console-on-ttyS4
+but now, the uart2 can still be used as a debug port with system log. If you don't want to output kernel messages, you can disable it as follow.
+Modify file /boot/extlinux/extlinux.conf.
+  append earlyprintk rw init=/sbin/init rootfstype=ext4 rootwait  root=UUID=8650cdca-49b0-4431-9667-5c639f6bab89