Signature Bytes

All AVR microcontrollers have a three-byte signature code, which identifies the device. This code can be read in both serial and parallel mode, also when the device is locked. The three bytes reside in a separate address space. For the device signature bytes, there are differences between ATmega48/88/168 and ATmega48PB/88PB/168PB, see the table below for more detail.

Table 1. Device ID
Part Signature Bytes Address
0x000 0x001 0x002
ATmega48/V 0x1E 0x92 0x05
ATmega48PB 0x1E 0x92 0x10
ATmega88/V 0x1E 0x93 0x0A
ATmega88PB 0x1E 0x93 0x16
ATmega168/V 0x1E 0x94 0x06
ATmega168PB 0x1E 0x94 0x15