There is bug related to watchdog in original old Arduino bootloader. You can switch to different bootloader, e.g. "Optiboot". Explanation
Explanation of issue from ATmega328 datasheet"ATmega48A/PA/88A/PA/168A/PA/328/P datasheet , section 10.10.5 Watchdog Timer, page 48:
If the Watchdog is accidentally enabled, for example by a runaway pointer or brown-out condition, the device will be reset and the Watchdog Timer will stay enabled. If the code is not set up to handle the Watchdog, this might lead to an eternal loop of time-out resets. To avoid this situation, the application software should always clear the Watchdog System Reset Flag (WDRF) and the WDE control bit in the initialization routine, even if the Watchdog is not in use.
Reset from button is not helping, only power off/on reset give device change to boot again (and flash new software). Explanation of this, from 11.9.1 MCUSR – MCU Status Register, page 54:
Bit 3 – WDRF: Watchdog System Reset Flag This bit is set if a Watchdog System Reset occurs. The bit is reset by a Power-on Reset, or by writing a logic zero to the flag.
There is bug related to watchdog in original old Arduino bootloader. You can switch to different bootloader, e.g. "Optiboot". Explanation of issue from ATmega328 datasheet"
If the Watchdog is accidentally enabled, for example by a runaway pointer or brown-out condition, the device will be reset and the Watchdog Timer will stay enabled. If the code is not set up to handle the Watchdog, this might lead to an eternal loop of time-out resets. To avoid this situation, the application software should always clear the Watchdog System Reset Flag (WDRF) and the WDE control bit in the initialization routine, even if the Watchdog is not in use.
Reset from button is not helping, only power off/on reset give device change to boot again (and flash new software). Explanation of this:
Bit 3 – WDRF: Watchdog System Reset Flag This bit is set if a Watchdog System Reset occurs. The bit is reset by a Power-on Reset, or by writing a logic zero to the flag.
There is bug related to watchdog in original old Arduino bootloader. You can switch to different bootloader, e.g. "Optiboot".
Explanation of issue from ATmega48A/PA/88A/PA/168A/PA/328/P datasheet , section 10.10.5 Watchdog Timer, page 48:
If the Watchdog is accidentally enabled, for example by a runaway pointer or brown-out condition, the device will be reset and the Watchdog Timer will stay enabled. If the code is not set up to handle the Watchdog, this might lead to an eternal loop of time-out resets. To avoid this situation, the application software should always clear the Watchdog System Reset Flag (WDRF) and the WDE control bit in the initialization routine, even if the Watchdog is not in use.
Reset from button is not helping, only power off/on reset give device change to boot again (and flash new software). Explanation of this, from 11.9.1 MCUSR – MCU Status Register, page 54:
Bit 3 – WDRF: Watchdog System Reset Flag This bit is set if a Watchdog System Reset occurs. The bit is reset by a Power-on Reset, or by writing a logic zero to the flag.
There is bug related to watchdog in original old Arduino bootloader. You can switch to different bootloader, e.g. "Optiboot". Explanation of issue from ATmega328 datasheet"
If the Watchdog is accidentally enabled, for example by a runaway pointer or brown-out condition, the device will be reset and the Watchdog Timer will stay enabled. If the code is not set up to handle the Watchdog, this might lead to an eternal loop of time-out resets. To avoid this situation, the application software should always clear the Watchdog System Reset Flag (WDRF) and the WDE control bit in the initialization routine, even if the Watchdog is not in use.
Reset from button is not helping, only power off/on reset give device change to boot again (and flash new software). Explanation of this:
Bit 3 – WDRF: Watchdog System Reset Flag This bit is set if a Watchdog System Reset occurs. The bit is reset by a Power-on Reset, or by writing a logic zero to the flag.