BASH Script to Monitor the CPU Frequency and Temperature on Raspberry PI

We can write a BASH Script to print out the current CPU frequency and temperature on Raspberry PI.

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#pi@raspberrypi:~ $ cat ./cpu_freq.sh 
#!/bin/bash
 
temp=`head -n 1 /sys/class/thermal/thermal_zone0/temp | xargs -I{} awk "BEGIN {printf \"%.2f\n\", {}/1000}"`
 
echo $((`cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq`/1000)) MHz, $temp degrees

#pi@raspberrypi:~ $ cat ./cpu_freq.sh 
#!/bin/bash

temp=`head -n 1 /sys/class/thermal/thermal_zone0/temp | xargs -I{} awk "BEGIN {printf \"%.2f\n\", {}/1000}"`

echo $((`cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq`/1000)) MHz, $temp degrees

Then, we can simpily run the following BASH command to monitor the CPU frequency and Temperature for Raspberry PI every few seconds:

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# monitor interval: every 3 seconds
while : ; do ./cpu_freq.sh; sleep 3; done

# monitor interval: every 3 seconds
while : ; do ./cpu_freq.sh; sleep 3; done

This is super useful if you are overclocking your raspberry PI e.g. 4B model you can tweak/overclock the ARM CPU to 2147 MHz and GPU to 750 MHz. You can modify the /boot/config.txt. Latest Raspberry PI models will automatically throttle the CPU if temperature gets too hot.

#uncomment to overclock the arm. 700 MHz is the default.
over_voltage=6
arm_freq=2147
force_turbo=1
gpu_freq=750

The `force_turbo` will enable CPU to run at maxium frequency even it is idle. After overclocking, you may also need to reduce the CPU temperature by plugin a heatsink or external Fan.

Most Raspberry PI External Fans are on 5V power – which you can see which two pins are for this by using the Raspberry PI utility pinout.

Overclocking Raspberry PI 4 to 2147MHz

Just make sure you have a good cooling for CPU before you overclock the Raspberry PI ARM CPU.

Raspberry Pi

• Visiting The Raspberry Shop in Cambridge UK
• Overclocking ARM CPU of Raspberry PI 4 and 400 with Temperature Cooling Measures
• BASH Script to Monitor the CPU Frequency and Temperature on Raspberry PI
• All-In-One Raspberry PI 400 Kit - Personal Computer Kit with Raspbian OS
• How to Monitor the CPU Temperature of Raspberry PI using Python Script?
• Use PHP Script to Monitor Temperature and Uptime for Raspberry PI in the Browser
• Review: Raspberry PI B Plus Model
• Different Approaches to Reduce the CPU Temperature of Raspberry PI
• Test SD Card Speed on Raspberry PI
• Remote Desktop Connection for Raspberry PI (xrdp)
• Using a external USB cooler fan to drop temperature of Raspberry PI (Model B) from 51 degrees downto 40 degrees for just ten minutes
• How to Get the CPU Temperature on Raspberry PI using BASH Script?
• Apache Server (PHP + MySQL) on Raspberry PI

–EOF (The Ultimate Computing & Technology Blog) —