Note that a hardware reset, if it happens without a power down cycle will typically not modify the contents of RAM. It is my conclusion that the RAM state after a "reset" is generally unknown. A reset of any type. Thus the following...

A) You should never write code that depends upon the current RAM content after a reset sequence code start up until that RAM has been set to a reliable and know state.

B) I have yet to see a microcontroller that provides a RAM area that guarentees the state of the RAM contents after a power on reset sequence.

Mike Karas