RP2 has no eeprom, is there a work around to store parameters that can be retreived on boot up ?

[ADenislebel]

I'm a newbie to both the RP2 and Micropython. I'm attempting to port my home automation project from an old 8 bit MCU programmed in C to the first generation RP2 board. My issue is how I can get around not having any EEPROM on the RP2 for storing configuration parameters that could be recalled upon boot up. Looking for a software based work around before I consider adding an external serial EEPROM chip to my hardware.
Thanks Denis Lebel

[robert-hh]

What stops you from storing it into a file on the board? The easiest way is to format the parameters as a Python file, which can be imported, like:

param1 = xyz
param2 = abc

Or as a JSON file?

[ADenislebel]

Ok, I already have the parameters as defaults in a list(prm1,parm2...) that I call up on startup. When my automation is running a menu allows changing them to suite the user preferences. So is there a mechanism to re-write a config.py file to flash within the Micropython environment so the changed values can be restore on the next boot up? I will look closely at the docs and attempt to identify how I could proceed to do so.
Regards Denis Lebel

[robert-hh]

You can use the normal Python file operations like open(), read(), write() to open or create, read and write files. Thta's what mpremote or other IDEs do. Once imported, a Python file like config.py can be rewritten, and on the next import the new content will be used

[ADenislebel]

Ok I will attempt/learn to do so. Thanks from a grateful newbie, Denis

[scruss]

or rather than rewriting a Python file — which requires careful attention to formatting — maybe read/write a JSON file instead

[ADenislebel]

Thanks! After another user pointed out that the open() builtin function allows writing directly to flash I've successfully created a Config.txt file where I save my configuration parameters and read it back upon boot up. Have a nice day...Denis

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On Mon, Mar 31, 2025 at 5:24 PM Stewart Russell ***@***.***> wrote: or rather than rewriting a Python file — which requires careful attention to formatting — maybe read/write a JSON <https://docs.micropython.org/en/v1.24.0/library/json.html> file instead — Reply to this email directly, view it on GitHub <#17054 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEFK5EIJVYNLXL24ZNLI7BL2XGW7JAVCNFSM6AAAAAB2ELLA6OVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTENRYGE2DMOI> . You are receiving this because you authored the thread.Message ID: ***@***.*** com>