Update random.adoc

Details about the max value managed by the Random Number Generator

Author: SimonePDA

Language/Functions/Random Numbers/random.adoc

@@ -86,5 +86,7 @@ If it is important for a sequence of values generated by `random()` to differ, o
 
 Conversely, it can occasionally be useful to use pseudo-random sequences that repeat exactly. This can be accomplished by calling `randomSeed()` with a fixed number, before starting the random sequence.
 
+The `max` parameter should be chosen according to the data type of the variable in which the value is stored. In any case, the absolute maximum is bound to the `long` nature of the value generated (32 bit - 2,147,483,647). Setting `max` to a higher value won't generate an error during compilation, but during sketch execution the numbers generated will not be as expected.
+
 --
 // HOW TO USE SECTION ENDS