Thank all for helping me at the thread "How to do CRC on the ROM?" I am
considering using 16C662 and its feature Parity Error Reset (PER). Maybe UL
can accept that? I will ask.

Meanwhile, I need to do a RAM check.

I already know that I need to scan the RAM, write 0xAA and read back; write
0x55 and read back to varify the integraty of the RAM. But I don't know how
and when to use that in the code. Do I need to test the whole RAM memory at
the same time? Or one word at a time during different operation of the
software? I also read from somewhere that due to the consitently changing
nature of the RAM, I cannot use C to do it. Yet, someone tell me I still can
as long as I am cautious and not to do something, etc.

In other words, I am still not very clear how to do a RAM check.

Can those who are more experienced give me a little guidance?

A small piece of demo code will help greatly.

Thanks!!!

Tony

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