Measuring CPU temperature

[otalado]

Today, I set up SSH public key authentication on my RPI5B running Armbian-unofficial 24.8.0-trunk Bookworm. During the test, I noticed that the initial SSH session message displayed the CPU temperature and other details. Unfortunately, the vcgencmd utility provided by the Raspberry Pi Foundation doesn't work on Armbian. I'm looking to understand how the temperature, CPU clock, and GPU clock are measured, and if possible, I'd like to receive some code to do so.

[otalado]

I searched the github.com looking for possible answers to my problem. WendySanarwanto published a few scripts under the title arm-cpu-temp.  I just looked for the one dedicated to Banana Pi M3 and it turned out that the folders are about the same as for the RPI5B. For anyone interested, I have included a sample bash script below:

#!/bin/bash
echo 'Temperature: '$((`cat /sys/class/thermal/thermal_zone0/temp` /1000)) ' °C'
echo "CPU-0 Frequency: "$((`sudo cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq` /1000)) ' Mhz'
echo "CPU-1 Frequency: "$((`sudo cat /sys/devices/system/cpu/cpu1/cpufreq/cpuinfo_cur_freq` /1000)) ' Mhz'
echo "CPU-2 Frequency: "$((`sudo cat /sys/devices/system/cpu/cpu2/cpufreq/cpuinfo_cur_freq` /1000)) ' Mhz'
echo "CPU-3 Frequency: "$((`sudo cat /sys/devices/system/cpu/cpu3/cpufreq/cpuinfo_cur_freq` /1000)) ' Mhz'