Changes
/* Compile custom kernel */
* For example, on Linux Mint 19 with kernel 4.15+ serial port initially detected as /dev/ttyS6, but then device node is absent in the /dev/ directory
=== Temporary solution ===
* Ensure latest BIOS is installed: [[Fitlet2:_BIOS_Files]]
* Install development Ubuntu kernel provided by Canonical Kernel Team
</pre>
* Missing device node /dev/ttyS6 will appear now as /dev/ttyHS1
<pre>
# Test with serial loopback cable:
$ sudo -i
$ echo "12345678" > /dev/ttyHS1
</pre>
=== Compile custom kernel ===* The above temporary solution works for Ubuntu based distributions like Linux Mint, for other distributions, see below.
* Another way is to get serial port working is to recompile your kernel manually and unset CONFIG_SERIAL_DEV_BUS in menuconfig
* The configuration path: Device Drivers > Character devices > Serial device bus
* We've build example .deb kernel packages for Debian 10, missing device node will appear as /dev/ttyS2:
<pre>
# Download and install the kernel packages:$ wget https://pathfit-iot.com/tofiles/download/fitlet2/sw/images/Linux/Kernel-packages/linux-headers-4.19.67-compulab.2019.09.11_4.19.67-compulab.2019.09.11-1_amd64.deb$ wget https://pathfit-iot.com/tofiles/download/fitlet2/sw/images/Linux/Kernel-packages/linux-image-4.19.67-compulab.2019.09.11_4.19.67-compulab.2019.09.11-1_amd64.deb
$ sudo dpkg -i linux-headers-* linux-image-*
$ sudo reboot
$ cat /boot/config-4.19.67-compulab.2019.09.11 | grep CONFIG_SERIAL_DEV_BUS
# CONFIG_SERIAL_DEV_BUS is not set
$ sudo -i
$ echo "12345678" > /dev/ttyS2
