Locking portions of code, while allowing easy access to othe

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Is it possible to program the 8535 chip so an end user can change the look-up table values, but the basic code of the processor cannot be accessed? This is how aftermarket fuel injection systems are set up, but I haven't found any info on this so far for avr microprocessors.
Thanks in advance,
Tom

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Why not use EEprom for the tables ?

Jens

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It is surely not possible to do this with the code lock bits. You should use the EEPROM for the tables. If internal EEPROM is not enough, consider connecting an external one.

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Hello,

Jens and Alexander are right. The AT90S8535 doesn't support the kind of code division you're requesting, nor can a program in Flash write to the Flash itself.

I suggest the same approach as do Jens and Alexander. The EEPROM is normally used as data space, while the Flash is used as program space.

With kind regards,

Morten, Atmel tech. support FAE