ESP8266 Community Forum

Hi Dude,

Have you encountered the chip id of esp8266 changed ?

Recently some of our esp8266 modules have its chip id changed unexpectedly. e.g. 0x202BXXXX changed from 0x002BXXXX, and 003BXXXX changed from 002BXXXX.

I could guess where the change might be from. But is this means that the chip id could not be assumed "unchangeable' definitely for some purpose.

Or, is there any way to avoid such a kind of change?

Best

That's interesting indeed.

Where do you get the chip id from? Here for example (my code) you see that chip is actually only three bytes wide and corresponds to the lower three bytes of the mac address. This is with the latest 3.x (HEAD) SDK software.

$ espif esp25 s
> firmware
> date: Dec 19 2020 16:06:30
> git commit: 2384ff8 stats: add git commit oneline message to stats output.
>
> heap:
> free: current: 13416, min: 13416, max: 14136
>
> stack:
> bottom: 0x3ffffffc (1048575 kiB), top: 0x3fffeb30 (1048570 kiB), initial: 0x3fffff50 (172), current: 0x3ffffee0 (284)
> size: 5324, painted: 5152, not painted: 172
> currently used: 284/5%, max used: 1644/30%, unused: 3680/69%
>
> system
> id: 69:8b:50
> cpu frequency: 80 MHz
> SDK version: 3.0.5-dev(52383f9)
> reset cause: power on reset

$ espif esp25 sw
> autoconnect: on
> phy mode: 802.11n
> sleep mode: none
> channel: 1
> signal strength: -77 dB
>
> ap mac address: 52:02:91:69:8b:50
> ap ip address: 0.0.0.0
> ap gateway: 0.0.0.0
> ap ip netmask: 0.0.0.0
>
> station mac address: 50:02:91:69:8b:50
> station ip address: 10.1.12.25
> station gateway: 10.1.12.1
> station ip netmask: 255.255.255.0

I do exactly the same as erik and have never seen it change - this is really weird

It looks like TS is talking about the MAC address not the chip id. In that case, the MAC address used for the Access Point mode is different to the MAC address used for the STA (client) mode, like this:

> ap mac address: 52:02:91:69:8b:50
> station mac address: 50:02:91:69:8b:50

Maybe this is the issue.