Firmware Upgrade 2021: Aot4221sr

| Item | Specification / Action | |------|------------------------| | | USB-to-I²C isolator (e.g., FT4232H) or dedicated programmer per AOT application note AN-4221 | | Supply Voltage | 5.0V ±1% on VDD pin; ensure no load on VOUT during upgrade | | Firmware Binary | Signed .aot or .hex with CRC16 checksum (validate using aot_checksum -c firmware.bin ) | | Backup | Dump current firmware via aot_read --full if device is unlocked |