7 Comparison Between Processors
The ATmega48PB/88PB/168PB differ only in memory sizes, boot loader support, and interrupt vector sizes. The table below summarizes the different memory and interrupt vector sizes for the devices.
| Device | Flash | EEPROM | RAM | Interrupt Vector Size |
|---|---|---|---|---|
| ATmega48PB | 4KBytes | 256Bytes | 512Bytes | 1 instruction word/vector |
| ATmega88PB | 8KBytes | 512Bytes | 1KBytes | 1 instruction word/vector |
| ATmega168PB | 16KBytes | 512Bytes | 1KBytes | 2 instruction words/vector |
ATmega88PB/168PB support a real Read-While-Write Self-Programming Mechanism (SPM). The SPM instruction can only execute from the separate Boot Loader Section. In ATmega48PB there is no Read-While-Write support and no separate Boot Loader Section. The SPM instruction can execute from the entire Flash.