Flashing an EEPROM dump typically requires a hardware programmer (like a CH341A) to write the data directly to the chip if the DVR is completely unresponsive.
: For broader compatibility, this Firmware Download Guide provides a list of V4.02.R11 firmware for Hisilicon SoC-based DVRs (including the Hi3520D chipset used in your model). How to Identify the Correct Version Download AHB700XT8 3520D rar
: If the device still boots, navigate to [System info] > [Version] to find your current firmware string. Flashing an EEPROM dump typically requires a hardware
Before flashing any firmware, verify your hardware to avoid "bricking" the device: Download AHB700XT8 3520D rar