user15630: I use Arduino Pro Mini. As I know, every MCU has a number. Different MCU has different number.  How to get it ?

user313: Could you be confusing the term micro-chip (often applied to any tiny, programmable electronic device) with the manufacturer named "Microchip" (who make the PIC series of micro-controllers, among many other products)? Microchip (the company) does make a line of products that have individually unique IDs. Most manufacturers do not provide unique IDs in their micro-controller devices, and AVR's Atmega 328 series devices do not have unique ID's.

user28768: Arduino Pro mini is based on Atmega328 which does not have a unique ID. It has only device signature which you can read if you turn on Show verbose output during upload in Arduino IDE's File > Preferences.

15630: <p>I use Arduino Pro Mini. As I know, every MCU has a number. Different MCU has different number.  How to get it ?</p>
 313: <p>Could you be confusing the term micro-chip (often applied to any tiny, programmable electronic device) with the manufacturer named "Microchip" (who make the PIC series of micro-controllers, among many other products)? Microchip (the company) does make a line of products that have individually unique IDs. Most manufacturers do not provide unique IDs in their micro-controller devices, and AVR's Atmega 328 series devices do not have unique ID's.</p>
 28768: <p>Arduino Pro mini is based on Atmega328 which does not have a unique ID. It has only <code>device signature</code> which you can read if you turn on <code>Show verbose output during upload</code> in Arduino IDE's <strong>File</strong> > <strong>Preferences</strong>.</p>
