Programm MC912D60ACPV8

[hector]

Hi, I 'm trying to read and write the micro MC912D60ACPV8, but the micro is protected against reading and writing.

How I can read it?

[iggi]

Hello Hector,

The flash memory in the S12(X) can be locked using two different features: Memory protection and/or Memory security.

Memory Protection is designed to prevent accidental modification of the flash content, for example: software error or malfunction may try to overwrite data or code in flash memory, but if you have protected the flash it will not be modified unless you deactivate the protection.

Flash memory is divided in sectors, you can select which sectors will be protected using the FPROT register, please refer to the section 3.3.5 in the document S12FTS128K1V1.pdf and the chapter "Flash Memory Protection" in the application note AN2400 for details to use this feature. In case you don´t have the application note you can download it from the following link:

http://www.freescale.com/files/microcontrollers/doc/app_note/AN2400.pdf

Flash protection can be enabled or disabled by your application software writing the appropriate bits in the FPROT register, it does not require a password by itself but you can write your application to receive a password from a serial port or from a keyboard and modify the FPROT register as needed. Notice that  flash protection is a safety feature that protects the memory from internal rewriting, but it does not block the external access to the memory.

Flash security is a different feature, it is intended to prevent unauthorized access to the flash through the BDM channel: In Normal Single Chip Mode and Expanded Modes BDM operation on the microcontroller is completely disabled, in Special Single Chip Mode, BDM firmware commands on the microcontroller are disabled. For more detailed information about the security, please refer to section "NVM Security" in application note AN2400.

After the security is activated, the flash can only be accessed after it is unsecured. The secured flash can be unsecured by one of the following methods:

1. Backdoor Key Access
2. Reprogramming the Security Bits
3. Complete Memory Erase

More details about this feature you can find in following document:

S12(X) MCU Security

Regards,

iggi

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[RadekS]

Hi Hector,

the HC12D60A do not contain security feature.

Therefore there will be probably some problem in BDM communication or reset.

Please check mode selection (MODA, MODB, BKGD pins) and try disabling all external sources of reset - like external watchdog.

Unfortunately I don’t have any board with HC12D60A MCU for testing. This MCU is quite old piece of hardware.

Please check also BDM cable and connector orientation.

HC12D60A should contain internal charge pump, therefore 12V for programming is not necessary (in opposite to HC12D60).

I hope it helps you.

Have a great day,
RadekS

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Note: If this post answers your question, please click the Correct Answer button. Thank you!
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[kef2]

• the HC12D60A do not contain security feature.

There's BDM lockout feature on D60A. See NOBDM bit and shadow register.

[RadekS]

Hi Edward,

You are right, I missed that feature.

Best Regards

RadekS