MicroPython Forum (Archive)

Posted: **Mon May 07, 2018 10:46 am**

Hi there,
I have a little problem with changing the CPU frequency on ESP32.

On ESP8266, you can do this:

>>> import machine
>>> machine.freq()
80000000
>>> machine.freq(160000000)
>>> machine.freq()
160000000

See here.

But on my ESP32, I will get this result:

Code: Select all

>>> import machine
>>> machine.freq()
240000000
>>> machine.freq(160000000) 
>>> machine.freq()
240000000

80MHz, 160MHz and 240MHz should be possible (right?) - but why I can not change it via machine.freq([frequence]) on ESP32

On ESP32 MicroPython v1.9.3-548-gcd12483d9-2018-04-19 is installed.

Posted: **Mon May 07, 2018 10:52 am**

not sure but my understanding is that it has to be a divider of the full spped of the clock, 240MHz for ESP32 and a divider of 160MHz for the ESP8266.

Speeds used on ESP8266 is 80Mhz and 160Mhz
Speeds used on ESP32 is 120MHz and 240Mhz

Posted: **Mon May 07, 2018 11:03 am**

ESP32-datasheet:
Max-Speed: 240MHz
Normal-Speed: 80MHz
see here (page 21).

Code: Select all

>>> machine.freq(120000000)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: frequency can only be either 80Mhz, 160MHz or 240MHz

So, 80MHz, 160MHz or 240MHz should be possible with MicroPython (with 120MHz you will get this ValueError)?

(Default is at Max-Speed 240MHz - on the ESP8266 the Max-Speed is 160MHz, but the default is on 80MHz)

Posted: **Sat Feb 02, 2019 6:11 pm**

This problem is still existant in v1.1

The CPU freq can't be changed with
machine.freq(80000000)
to 80MHz

Posted: **Sun Feb 03, 2019 5:08 am**

Yes, the implementation of freq() is actually commented out in MicroPython.

Apparently it wasn't working in the ESP-IDF - but I've heard that recently it was resolved. Anyone know? Should be pretty easy to add if it's now working...

MicroPython Forum (Archive)

Changing the CPU frequency on ESP32

Changing the CPU frequency on ESP32

Re: Changing the CPU frequency on ESP32

Re: Changing the CPU frequency on ESP32

Re: Changing the CPU frequency on ESP32

Re: Changing the CPU frequency on ESP32