Jim Pantera

help... again with flash security

Discussion created by Jim Pantera on Dec 12, 2006
Latest reply on May 29, 2012 by Luis Hoyos
reference mc9s08rd32dwe processor
codewarrioir ide v5.7 & debugger v6.1

in the project S19 file i am asserting m(FFBF) = 0xFC and this should enable security. i start a a debug scession with this build and load it into the target. I notice the targets memory is displayed all zero's and this is an indication security is set. note m(FFB0 - FFBE) are set to 0xFF.

with the code loaded i remove the target from the debugger, do a reset on the target and begin normal target operation. I notice the targets firmware can write to its flash even tho the target is set secure. is this normal????

-i thought i have to use the back door key to do internal writes on a secure part
-the backdoor is one method. is another method to have a blank page of flash, do a blank_ck command (0x05) on the blank page of flash and the security will temporarly be removed?

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