Register range can edit or not

Neo_zhang

MC9S12DT256CPVE 0x0-0x3ff range is register, can it be written to all FF? Does this matter when I copy One chip to another?

lama

Hi,

The registers are RAM memory which loses content after power off. Each reset sets the registers to reset values described for each register in the data sheet. Some of the register are write once only which means that after the first write they are not re-writable till next reset. Also there are register which are loaded during reset automatically by a value stored in special fields of the flash memoroy (like register FPROT, FSEC, COPCTL,…)

When you copy content of one MCU to another the content of the register has no meaning because, as I wrote above, the content is either defined after reset (reset value of the register) or loaded from the special field (setup registers for security, protection, COP, ….)

Best regards,

Ladislav

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lama

Hi,

The registers are RAM memory which loses content after power off. Each reset sets the registers to reset values described for each register in the data sheet. Some of the register are write once only which means that after the first write they are not re-writable till next reset. Also there are register which are loaded during reset automatically by a value stored in special fields of the flash memoroy (like register FPROT, FSEC, COPCTL,…)

When you copy content of one MCU to another the content of the register has no meaning because, as I wrote above, the content is either defined after reset (reset value of the register) or loaded from the special field (setup registers for security, protection, COP, ….)

Best regards,

Ladislav