Winbond W79E201 Microcontroller Internal Memory Breaking

In order to carry out the Winbond W79E201 Microcontroller Internal Memory Breaking, engineer need to has the general idea about the security system as well as its protection mechanism in this Microcontroller, below we would like to introduce some features of it:

This bit is used to restrict the accessible region of the MOVC instruction. It can prevent the MOVC instruction in external program memory from  reading the internal program code.

When this bit  is set  to logic 0, a MOVC instruction in external program memory space will be able to access code only in  the external memory, not in the internal memory.

A MOVC instruction in internal program memory space will always be able to access the ROM data in both internal and external memory. If this bit is logic 1, there are no restrictions on the MOVC instruction.

This bit is used to enable/disable the encryption logic for code protection. Once encryption feature is enabled, the data presented on port 0 will be encoded via encryption logic. Only whole chip erase will reset this bit before Winbond W79E201 Microcontroller Internal Memory Breaking.

ABSOLUTE MAXIMUM RATINGS

Oscillator Control

W79E201 allow user to diminish the gain of on-chip  oscillator amplifier by using programmer to  set  the bit B7 of security register. Once B7 is set to 0, a  half of gain  will be decreased. Care must be  taken if user attempts to diminish the gain of oscillator amplifier, reducing a half of  gain  may improperly affect the external crystal operation at high frequency above 24 MHz. The value of R and C1,C2 may need some adjustment while running at lower gain.

Comments are closed.