[En-Nut-Discussion] NutMicroDelay tends to integer overflows

[Ole Reinhardt]

Hi all,

The calculations in NutMicroDelay tends to overflow on systems with fast
CPU if it is called with delay times of > a few milliseconds.

Especially when using NutDelay() NutMicroDelay may be called with large
delays.

One way to solve the problem is to use 64bit integers as intermediate
results in the delayloop calculations. Beside of beeing not very
efficient it brings big (linker) problems when using 64bit divisions.
See my former post

http://old.nabble.com/Strange-newlib-syscall-dependencies---linker-problems-when-using-64bit-integers-td33275220.html



So I decided to modify as less as possible and to just change the
comments:

We should not give parameter values > 10ms to NutMicroDelay.

As NutDelay calls NutMicroDelay(), I modified NutDelay so that
NutMicroDelay is called in a loop and waits for 1ms each time.


I don't like this solution very much but I don't see something better
for the moment.

Any ideas are wellcome.

Best regards,

Ole

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