Cracking ATmega16A Microcontroller Flash Memory
Cracking ATmega16A Microcontroller Flash Memory is a process to break atmega16a mcu fuse bit, readout heximal file from microprocessor atmega16a avr chip;
When the AVR exits from an interrupt, it will always return to the main program and execute one more instruction before any pending interrupt is served.
Note that the Status Register is not automatically stored when entering an interrupt routine, nor restored when returning from an interrupt routine. This must be handled by software.
When using the CLI instruction to disable interrupts, the interrupts will be immediately disabled. No interrupt will be executed after the CLI instruction, even if it occurs simultaneously with the CLI instruction.
The following example shows how this can be used to avoid interrupts during the timed EEPROM write sequence by attacking mcu atmega162 flash memory.
When using the SEI instruction to enable interrupts, the instruction following SEI will be executed before any pend- ing interrupts, as shown in the following example.
The interrupt execution response for all the enabled Microchip AVR® interrupts is four clock cycles minimum. After four clock cycles, the Program Vector address for the actual interrupt handling routine is executed by break mcu atmega16a flash memory. During this 4- clock cycle period, the Program Counter is pushed onto the Stack.