Break ATMEGA128L Protected MCU Flash Memory and recover embedded firmware from atmega128l microcontroller, readout flash memory program from atmega128l;
When the IVSEL bit is cleared (zero), the Interrupt Vectors are placed at the start of the Flash memory. When this bit is set (one) in the process of clone atmega32l microprocessor memory data, the Interrupt Vectors are moved to the beginning of the Boot Loader section of the Flash. The actual address of the start of the boot Flash section is determined by the BOOTSZ Fuses.
To avoid unintentional changes of Interrupt Vector tables, a special write procedure must be followed to change the IVSEL bit:
Interrupts will automatically be disabled while this sequence is executed. Interrupts are disabled in the cycle IVCE is set when crack atmega32 microcontroller flash memory, and they remain disabled until after the instruction following the write to IVSEL.
If IVSEL is not written, interrupts remain disabled for four cycles. The I-bit in the Status Register is unaffected by the automatic disabling.