>So, I'll ask my question again !! Is it normal that when your program uses
>1/5 of the total amount of memory, the UV erase time is about 20 minutes ???

Erase time depends upon the type of chip (most chips are different), the
type of UV lamp, the distance from the lamp to the chip, the brightness of
the lamp, the actual wavelength put out by the lamp, how clean the window
is on the chip, the age of the chip (how many erase/write cycles) and other
variables.

>Also, is it normal that the UV-erase time depends on the amount of memory
>used by a program ??

It has nothing to do with how much program space is used.  It does relate
somewhat to how good your programmer is, though, as some programmers may
not burn chips as thoroughly.

>And, if it IS normal, can someone give me a the full explanation ??

Good luck!  That will only confuse you more!

Andy

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     \    |   |    /          Andy Kunz
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