Question: We have a product that uses an external EEPROM for code storage. Is there a way to secure the firmware in the EEPROM so that a hacker cannot read the EEPROM?
Answer: It is not possible to protect the contents of the EEPROM from being read. The download mechanism requires that the EEPROM be readable. There is no encoding scheme available for the download process.
If you designed the device to download via the USB (a C0 load), it would still be possible to monitor the USB traffic to extract the firmware. It is also possible to read the internal memory via a 0xA0 vendor command.
