Resetting the 8515

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All;

I'm using the 8515 to receive serial data, process it a little bit, and send it back out. I don't want the data left in the micro after it's transmitted. Can I reset the micro and get rid of the volatile data? Do I really have to? If I do, how do I reset it in C?

Paul Lorenz

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As far as the data in the micro is not very secret, I dont see why you should reset it. If the data is in SRAM it will be either lost when power is disconnected or overwritten when new data is entered.

I don´t know C very well, so I can´t answer that one.

Björn Almgren
Sweden

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You can do a hard reset by enabling the watchdog timer and making sure it times out. You can do a soft reset by jumping to address 0, which is easily done in assembler from within most C compilers. Since a C program requires that the bss section be initialized to 0, ram will be erased. Make sure that the ram used is in the bss section.
The question bears repeating: Is the erasing of data for security purposes and if so, is there a method available to make the processor reveal what is in the data?

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This might be too obvious, but why not just overwrite the buffer after the data is sent and no longer needed? It would only be a fetw instructions in a loop in C, even if no memset() is available.

Lee