HC08

[m4rvell]

Hello there. I'm a newbie in the uC subject, but I have one question. Is there a way to secure HC08 processor to prevent reading with programmers such as BeeProg and other and to have access to read via Backgroud Debug Mode (with USBDM for example) ?

[tonyp]

Apparently you're interested in the HCS08 and not the HC08 (as the latter does not have BDM).

Besides, the two have completely different security methods.

So, for the HCS08 (aka 9S08 or S08) the protection is achieved with the SEC bits (SEC00 and SEC01) of the NVOPT register.  Normally, any value other than %10 means secure.

If you secure a device the only way to re-gain access to it is either to completely erase it, or to have enabled the BACKDOOR mechanism with an appropriate key which must be, however, entered from the app running inside the MCU.  The BDM cannot bypass security on its own even if you know the backdoor key bytes.

Hope this helps.

[m4rvell]

Thank You verry much for Your answer. Now i have other problem. I have unsecured processor (hcs08dz60 I've checked the security bit FOPT) and I can't read it with memory dump program. When I'm trying to do this I'm getting error: "Expected BDM command ACK missing". Could You please help me to bypass this error ?