: Often uses a 16MB SPI Flash (such as the W25Q128) to store the firmware.
: Visit the Napco Technical Library or Napco Access Pro to search for authorized software and firmware downloads.
: For older or "white-label" versions of Hi3521 boards, professional repositories like Unifore provide collections of V4.02.R11 firmware compatible with HiSilicon SoC-based DVRs. Update Process