Lpc2000

> The user manual of LPC2214 states that a reserved bit should not be 
> set to 1. Is it because of future compatibility issues or is it a 
> hardware requirement?, i.e., what if we set a reserved bit to 1. 
> will the IC burn or present undefined behaviour?

If you need to ask this question, you're living too close to the
bleeding edge. Undefined bits might, if set:

1. do nothing
2. do nothing on current masks, but do something spectacularly strange
on a future mask
3. activate an internal test mode feature that fries your external
hardware by activating "impossible" combinations of I/Os

I'm not surprised you didn't get an answer. The behavior is undefined.
You would get exactly the same (non-) answer if you asked "How safe is
it to run the chip twenty degrees above its absolute maximum rating?"

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Lewin A.R.W. Edwards
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