Restore AVR Microcontroller ATMEGA16L Heximal needs to break locked avr mcu atmega16l flash memory protection then copy flash code to new microprocessor atmega16L flash memory;
If an enabled interrupt occurs while the MCU is in a sleep mode, the MCU wakes up. The MCU is then halted for four cycles in addition to the start-up time, it executes the interrupt routine, and resumes execution from the instruction following SLEEP. The contents of the Register File and SRAM are unaltered when the device wakes up from sleep. If a reset occurs during sleep mode, the MCU wakes up and executes from the Reset Vector.
Note that the Extended Standby mode present in many other AVR MCUs has been removed in the ATmega16L, as the TOSC and XTAL inputs share the same physical pins to extract atmega16l microcontroller heximal code from flash memory. Figure 10 on page 25 presents the different clock systems in the ATmega16L, and their distribu- tion. The figure is helpful in selecting an appropriate sleep mode.
The MCU Control Register contains control bits for power management. The SE bit must be written to logic one to make the MCU enter the sleep mode when the SLEEP instruction is executed. To avoid the MCU entering the sleep mode unless it is the programmer’s purpose, it is recommended to set the Sleep Enable (SE) bit just before the execution of the SLEEP instruction.
When the SM2..0 bits are written to 000, the SLEEP instruction makes the MCU enter Idle mode, stopping the CPU but allowing SPI, USART, Analog Comparator, ADC, Two-wire Serial Interface, Timer/Counters, Watchdog, and the interrupt system to continue operating. This sleep mode basically halts clkCPU and clkFLASH, while allowing the other clocks to run.
Idle mode enables the MCU to wake up from external triggered interrupts as well as internal ones like the Timer Overflow and USART Transmit Complete interrupts. If wake-up from the Analog Comparator interrupt is not required when extract atmega16 mcu flash program, the Analog Comparator can be powered down by setting the ACD bit in the Analog Comparator Control and Status Register – ACSR. This will reduce power consumption in Idle mode. If the ADC is enabled, a conversion starts automati- cally when this mode is entered.
